JPS6264500A - Correcting device for bottom dead point position of slide of press machine - Google Patents

Abstract

PURPOSE:To always obtain a stable bottom dead center position by detecting a bottom dead center position of a slide by a sensor, comparing it with a position which has been set in advance and controlling the oil temperature of an oil path, expanding and contracting an oil-immersed bolster holding device and correcting it. CONSTITUTION:When a motor M5 is rotated, a crank shaft 7 rotates through a pulley 12, a belt 13 and a fly-wheel 10, and a slide 5 moves up and down by a connection screw 6 which has been connected to a crank pin 8a. A variance of a bottom dead center position of the slide 5 is detected by sensors 14, 14, and in case when an error has exceeded a prescribed value N times continuously, a CPU expands and contracts oil-immersed bolster holding devices 3A, 3A by an oil temperature of oil 3C in an oil bath 3B of a press machine 1 in accordance with a displacement quantity of the slide 5. As a result, the bottom dead center position of the slide 5 can be corrected automatically without causing a capacity loss of the press machine 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a bottom dead center position correction device for automatically correcting the slide bottom dead center position of a press machine.

(Prior art) Conventionally, press machines generally operate at high speed.
Another problem is that the bottom dead center position of the slide changes when the vehicle is operated for a long time.

The reason for this is that the higher the speed of the press, the greater the inertia applied to the slide, so even though the slide is balanced with an air balancer etc.
The bottom dead center position of the slide is lowered due to gaps around the crank, and when a press is operated for a long time, the heat generated by the press causes thermal expansion of connections and other joints, so the slide bottom dead center position is lowered due to gaps around the crank. The bottom dead center of the slide would drop due to thermal expansion of the frame (particularly the column and tie rod) if operation continued.

Therefore, in order to compensate for such changes in the bottom dead center position, conventional measures have been taken such as installing a stopper to limit the bottom dead center position or stopping the press machine each time to make fine adjustments. was.

(Problems to be Solved by the Invention) Among the above-mentioned conventional means for correcting changes in the bottom dead center position, in the case of the former, it is difficult to adjust the stopper in precision machining because it results in a loss of press machine capacity. In addition, in the case of an intruder, it is very time-consuming and the operation rate of the press is substantially reduced.

Therefore, in view of the above, the present invention aims to automatically correct the bottom dead center position without any loss in press capacity.

(Means for solving the problem) The technical means for solving the above problem is to install a slide bottom dead center position correction device of a press machine, a sensor for detecting the slide bottom dead center position of the press machine, and a sensor for detecting the slide bottom dead center position of the press machine. an oil bath formed to immerse the bolster holding device in oil; a heating section for raising the oil temperature in the oil bath; a cold sweat section for lowering the oil temperature; and a slide from the sensor. By controlling the heating section and the cooling section in response to a signal regarding the bottom dead center position of the slide, the oil temperature in the oil bath is adjusted to expand and contract the bolster holding device, and the bottom dead center position of the slide is set at a predetermined value. It consists of an oil temperature setting circuit that holds the oil in position.

(Function) Therefore, the operation of the slide bottom dead center position correction device of the press machine with the above configuration is such that the sensor detects the slide bottom dead center position and outputs a signal corresponding to the bottom dead center position to the oil temperature setting circuit. Then, the oil temperature setting circuit compares the preset slide bottom dead center position, and if the actual bottom dead center position is L lower than the set slide bottom dead center position, the oil temperature setting circuit controls the heating section and the cooling section. The slide bottom dead center position is corrected to the set bottom dead center position by adjusting the oil temperature in the oil bath, expanding and contracting the bolster holding device, and changing the position level of the bolster. .

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the general structure of the press 1. A bolster 3 is attached to the upper part of the bed 2 in a state where it is held horizontally on the upper surface of the bolster holding devices 3A and 3Δ.

The bolster holding devices 37\, 3Δ are arranged so as to be immersed in the oil 3C in the oil bath 3B.
B is provided with a supply port 3D for supplying oil 3C and a discharge port 3E for discharging oil 3C.

Four tie rods 4 are further provided upright on the bed 2. A connection screw 6 is swingably provided at the top of the slide 5, and this connection screw 6 is screwed onto a connection 8. Furthermore, the connection 8 is provided so as to be swingable relative to the crank bin 8a.

On the other hand, a flywheel 10 is provided on the crankshaft 7 which is rotatably supported by bearings 7a, 7a, and this flywheel 10 is connected via a belt 13 to a pulley 12 provided on the rotating shaft of the motor M5. has been done. Note that a variable speed motor is used as the motor M5.

On the other hand, two sensors 14 and 14 for detecting the bottom dead center position of the slide 5 are installed on the bolster 3 on the bracket 1.
They are provided at both ends of the bolster 3 via 4a and 14a, respectively. In this example, the sensor 1/L14 is a magnetic sensor having an internal coil (not shown). However, other methods such as capacitive sensors and ultrasonic sensors may also be used.

15 is a lower die attached to the bolster 3, and 16 is an upper die attached to the slide 5.

Next, the oil temperature control circuit 17 will be explained. In this example, the oil temperature control circuit 17 includes an oil temperature first node 17A shown in FIG. 2 and an oil temperature setting part 17B shown in FIG. 3. Therefore, first, the oil temperature adjustment section 17A will be specifically explained.

As shown in FIG. 2, the oil temperature adjustment section 17A mainly includes a cooling section 30 and a heating section 31, and the cooling section 30 further includes a condenser 32, a condenser fan 33, and a cooling tank 34.
, a cooling coil 35, a compressor 36, a dry filter 37, and a cabillary tube 38,
The heating section 31 further includes three heaters, a heating tank 40, and a thermistor SAI.

The cooling tank 311 is supplied with oil from the reservoir tank 43 by the circulation pump 42, and the oil supplied to this cold 11 tank 34 is supplied to the same cooling tank 3.
4. Connecting vibrator 41, heating tank 40 and discharge vibrator 4
4 to a reservoir tank 43.

On the other hand, the oil in the reservoir tank 43 is transferred to the oil feed pump 45.
is supplied to the oil bath 3B of the press 1f11 and transfers the heat held by the oil to the bolster holding devices 3A, 3A, or vice versa.
After taking away the heat held by 3A, it is collected from the outlet 3E of the oil bath 3B on return day 46 and transferred to the reservoir tank 4.
It is designed to be recycled to 3. In addition, 4T is a bypass vibe for circulating excess oil, and 48 is a press machine 1.
49 is a valve for adjusting the flow rate of excess oil, RE is a relief valve, and SA2 is a reservoir tank 4.
This is a thermistor for detecting the oil temperature.

Next, the oil temperature setting section 17B will be explained. As shown in FIG. 3, this oil temperature setting section 17B is composed of an oil temperature setting circuit 17Ba and a motor control circuit 17Bb. The motor control circuit 17Bb mainly includes a motor M5 for driving the breath*i, a motor M2 for driving the circulation pump 42, a motor M4 for driving the oil pump 45, a motor M2 for the compressor 36, and a motor M for the condenser fan 33.
It is configured as a sequence circuit for supplying power to 3 and 3.

Motor M1. M4. and M5 are activated by turning on the electromagnetic switch 24. When the electromagnetic switch 24 is turned on, the relays, MSl, MS3 . Since MS4 is activated, each normally open contact MS1a.

MS3a and MS4a are turned on and motor M1. M4, M
5 is activated), motors M2 and M3 are activated by turning on relay MS5 of temperature controller 23 (when relay Ms5 is activated, normally open contact MS5a is turned on and 1/- Since MS2 is activated, its normally open contact MS2a is turned on and the motor M
2 and M3 are activated).

In addition, OL1 to OL4 indicate overload relays, and F1 to F
4 indicates news, and MP indicates a motor protector that cuts off current in the event of overcurrent or temperature rise.

Next, the oil temperature setting circuit 17Ba will be explained.

The oil temperature setting circuit 17Ba is connected to the detection circuit 1 as shown in FIG.
8-D converter 19, CPU 20, and selection circuit 21
and a speed setting resistor circuit 22.

The detection circuit 18 includes an oscillation circuit, a voltage detection circuit, and an average value circuit (not shown). The high frequency output from the oscillation circuit is applied to a coil (not shown) of the sensor 14, 14, and the voltage values generated between both terminals of this coil are detected by a voltage detection circuit. In other words,
When the slide 5 approaches the sensor 14.14, the permeability of the coil of the sensor 14.14 changes depending on the proximity. Then, the voltage value generated between both terminals of the coil to which the high frequency voltage is applied changes, and this is detected by the voltage detection circuit. However, the value detected by this voltage detection circuit is a value that varies by 111 depending on the distance between the slide 5 at the bottom dead center position and the sensor 14. Each voltage value detected by this voltage detection circuit is input to an average value circuit, the average value of which is taken, and then input to the AD converter 19.

The Δ-D converter 19 is for converting the signal from the detection circuit 18 regarding the distance between the sensor 14 and the slide 5 at the bottom dead center position from analog to digital. The signal is input to CPIJ20.

The CPU 20 is located at a distance of 11 h from the A-D converter 19.
At the same time as inputting a signal related to The current limit value (this limit value is set as a binary value of plus and minus) N times (this N47
) value is set appropriately in advance) When the overflow occurs continuously, a predetermined control signal is generated depending on the degree of the overflow (the correspondence between the overflow amount and the control signal is stored in the CPU in advance). It is configured to output the set value to the selection circuit 21.

The selection circuit 21 inputs the control signal from the CPU 20, and selects the oil temperature setting resistors VRI to VR6 and R1a to VR6a in the temperature setting resistance circuit and starts the relay contact Rl- corresponding to this signal. 7a, a circuit for operating PL7a, and is configured as a kind of decoder.

Temperature setting resistor circuit 22a, 22Mt'6I Several temperature setting resistors (semi-fixed polycombs are used in this example) vR1~~'R6, VRla-VR6a, relay contacts RLI a-RL7a, PLI a~ The main components are PL6a and main variable resistors R1 and Rla. These relay contacts RL1a to RL6a are connected to the selection circuit 21
A relay R (not shown) is activated by a control signal from
When normally open contacts 1-1 to RL6 and PLI to PL6 are turned on, predetermined temperature setting resistors vR1 to VR6 and VR1a to R6a are selected.

Next, the temperature controller circuit 23 will be explained. This temperature controller circuit 23 is a heating part control circuit of a phase control type (not shown) mainly consisting of a triac, a trigger tJJT, and a thermistor SΔ1, and a thermistor SA2.
and a normal cooling product control circuit (not shown) mainly consisting of a comparator. This temperature controller circuit 23 is similar to the temperature control circuit for well-known heaters and coolers, and the temperature setting part that is normally controlled by changing the volume is replaced with a temperature setting part that is set in advance to a predetermined value. Resistance VRI~VR6゜■R1a~vR
6a to relay contacts RL1a to RL6a, PL1a to P
It is intended to be replaced by selection by L7a. That is, by selecting the resistor VR6, a temperature of 60 degrees, for example, is set, and the heating section control circuit (not shown) in the temperature controller circuit 23 controls the oil temperature adjusting section 17A so that the oil temperature is maintained at 60 degrees. This is what we do. By doing this, slide 5
If the bottom dead center position of 1 changes, the oil temperature can be set to a predetermined temperature corresponding to the changed position. The set value of the temperature corresponding to the degree is set in advance in the CPU 20).

Note that in this temperature controller circuit 23, the heater 39
The control of the cooling unit 30 shown in FIG. 2 by the control relay MS5 and the operation instruction thereof are performed by relay contacts RL7a and PL7a. This relay contact R
Relay contact RL7 (not shown) having L7a and PL7a
．． PL7 is also activated by a signal from selection circuit 21. That is, a predetermined threshold value is set in the CPU 20, and this threshold value is set in the CPU 20.
(corresponding to, for example, the interval 5!11111),
When the signal from the A-D converter 19 is above the threshold value (for example, il > 5 tra), the relay contact RL7a is activated together with a predetermined relay contact in the setting resistor circuit 22b in the CPU 20, and the signal is below the threshold value (for example, h <5
When the temperature is 1), the relay contact PL7a is activated together with a predetermined relay contact in the temperature setting resistance circuit 22b. In other words, relay contacts RL7a and P L7
A is a kind of activation switch for the cooling product control circuit and the heating section control circuit in the temperature controller 5 circuit.

In the above configuration, when the motor M5 is rotated, the crankshaft 7 is rotated via the pulley 12, belt 13, and flywheel 10. Then, the slide 5 is moved up and down in the drawing by the connection screw 6 connected to the crank bin 8a.

That is, the press is performed by the vertical movement of the slide 5.

On the other hand, the bottom dead center of the slide 5 is detected by the sensor 14.14, and a signal related to the distance between the sensor 14 and the slide 5 obtained thereby is sent to the CPLI2O via the detection circuit 18 and the A-D converter 19. is input to.

As mentioned above, the signal input to the CPU 20 is
Calculate the difference between tJ20 and the preset reference value (reference distance h), and calculate the difference between the two and the preset limit value N times (the value of N is set appropriately in advance). When the number of overpasses is consecutively exceeded, a predetermined control signal is output to the selection circuit 21 in accordance with the degree of overflow. Then, the selection circuit 21 responds to the control signal (
(This correspondence relationship is set in advance) A predetermined relay (not shown) is activated.

Now, for example, assuming a lifting platform where the bottom dead center position has risen above the reference value, the CPU 20 selects to set the oil to an oil temperature corresponding to this displacement amount (in this case, the oil temperature will be increased). A predetermined signal is sent to the circuit 21 to activate the relay. For example, if these relays are 1) L2 and PL7, their normally open contacts PL3a and PL7a are turned on, the mi setting resistor VR3a is selected, and a heating control circuit (not shown) is activated (in this case, the (The relay contacts that were turned on will naturally be released). For this purpose, terminal A of the temperature controller circuit 23.

The resistance value of the temperature i1u constant resistor VR3a and the main variable resistor R1a is set in B, and the temperature of the heating control circuit (not shown) in the humidity controller 1 to the roller circuit 23 is thereby set. In other words, the amount of heat generated by the heater 39 is controlled so that the temperature corresponds to the resistance value set between the terminals A and B. Therefore, in this case, since the oil temperature rises, the bolster holding devices 3Δ, 3A thermally expand due to the oil 3C in the oil bath 3B of the brace ^1, raising the position of the bolster 3, and causing the oil 3C to rise. The bottom dead center, which had been at that time, will now fall to the standard value. In addition, when the bottom dead center position has fallen, the cooling unit 30 is operated this time by the same control as described above, and the bottom dead center position is corrected.

In this embodiment, the slide 5 is controlled by the sensor 14.
The CPU 20 detects the variation in the bottom dead center position of the slide 5, and if this variation, that is, the error in the bottom dead center position exceeds a predetermined value N times in a row, the CPU 20 detects this and changes the amount of displacement of the slide 5. A predetermined relay is activated in order to change the set value of the oil temperature to a temperature corresponding to the temperature. In other words, when the bottom dead center position falls, the oil setting temperature is lowered by a predetermined temperature according to the degree of the fall.
The holding devices 3A, 3A are contracted, and on the other hand, when the bottom dead center position rises, the bolster holding devices 3A, 3A are expanded by raising the set temperature of the oil by a predetermined temperature according to the degree of rise. This corrects the bottom dead center position of the slide 5.

In addition, in this example, warm II! Setting resistance circuit 22a.

Although the number of temperature setting resistors 22b is six in this example, this number may be increased or decreased as necessary.

(Effects of the Invention) As described above, the present invention includes a senna for detecting the bottom dead center position of the slide, a heating section for increasing the temperature of the oil, and a cold fJI section for lowering the temperature. , an oil temperature setting that controls the temperature of the oil to keep the bottom dead center position of the slide constant by controlling the cooling section and the heating section in response to a signal sent from the sensor to the bottom dead center position of the slide. By configuring the bottom dead center position correction device of the slide of the press machine from the circuit, a stable bottom dead center position can always be obtained without any loss of capacity of the press machine and regardless of the operating condition of the press machine. This has an excellent effect.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the structure of the metal body of a press machine according to an embodiment of the present invention, Fig. 2 is an explanatory diagram showing the main body of the oil-drain adjustment section, and Fig. 3 is an explanatory diagram showing the main body of the oil temperature setting section. FIG. 1...Press machine 3...Bolster-3A...
・Bolster holding device

Claims (1)

[Claims] a sensor for detecting the bottom dead center position of the slide of the press; an oil bath formed to immerse the bolster holding device of the press in oil; a heating section for raising the oil temperature of the oil bath; and a cooling section for lowering the bottom dead center position of the slide, and controlling the heating section and the cooling section in response to a signal from the sensor regarding the bottom dead center position of the slide to adjust the oil temperature in the oil bath to control the bolster holding device. A slide bottom dead center position correcting device for a press machine, comprising an oil temperature setting circuit that expands and contracts to maintain the bottom dead center position of the slide at a predetermined position.