JPH03219108A - Controller for temperature rising-up of operating oil - Google Patents

Abstract

PURPOSE:To restrain a temperature rising-up operation to the minimum to be required by providing a circuit for detecting an actual temperature of operating oil, a setter/display of a rising-up temperature and an allowable value, a circuit for detecting the rising-up temperature an an allowable value, a circuit for detecting the rising-up of a power source at the start of an operation, a circuit for comparing an allowable lower limit with an oil temperature, and a circuit for generating a temperature rising-up signal when the oil temperature is lower than the allowable lower limit. CONSTITUTION:A temperature of operating oil 14 is detected by a temperature sensor 31 and inputted together with a difference between a rising-up temperature and an allowable value of the operating oil 14 of a setter/display 34 into a comparison circuit 35 via an A/D converter 32 and a linearizer 33. A judgement signal is inputted into a temperature rising-up signal generating circuit 36 together with a signal output from a rising-up signal detection circuit 37 of an operation starting power source. The temperature rising-up signal generating circuit 36 inputs the judgment signal output from the comparison circuit 35 into a driver 38 together with a selection signal of a temperature rising-up operation of the setter/display 34, and operates an electromagnetic changeover valve 22 of a circuit 20 for rising up a temperature of the operating oil only when the temperature rising-up operation is required, to supply oil discharged from a pump 21 into a passage resistor 23 and rise up the temperature. Therefore, any defective control can be prevented, and the rising-up operation can be restrained to the minimum to be required.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a hydraulic oil temperature increase control device in a machine such as an oilfield-driven injection molding machine, and in particular to a device for controlling the temperature of hydraulic oil at the start of operation. The present invention relates to a device for raising the temperature of the fuel to a temperature increase value that is the temperature of a steady operating state.

(Prior art) For example, an oil field driven injection molding machine is equipped with a hydraulic oil temperature raising device to ensure accurate mold opening/closing and all injection molding operations, and at the start of operation, the hydraulic oil temperature is kept at the steady operating temperature. The temperature is raised to a certain value, and the molding operation is started when the temperature of the hydraulic oil becomes stable.

(Problem to be Solved by the Invention) By the way, a general hydraulic oil temperature raising device is designed to maintain the hydraulic oil in the entire oil field operating circuit in a steady state of operation by applying hydraulic oil gold to the oil field operating circuit and performing idling operation. A method is adopted in which the temperature is raised to a temperature of 1,000,000, so that molding operation cannot be started in trenches where the hydraulic oil reaches the temperature rise value. Although this method is necessary for accurate operation, it is necessary to stop the machine for a relatively short period of time, such as during a rest period, and to adjust the temperature of the hydraulic oil against a temperature increase of, for example, 40 to 50 degrees Celsius. Even if there is a relatively small drop in the value, idling is required when operation is restarted.

For this reason, operators often use hydraulic fluid temperature control devices'
1 (For JFF-type machines, there were cases where operation control failures occurred where it was not possible to accurately open and close the mold or perform one injection operation.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a hydraulic oil temperature increase control device that can suppress the operation of increasing the temperature of the hydraulic oil to the necessary minimum without substantially causing operational control failures. It is an object.

[Structure of the invention]

(Means for Solving All Problems) To achieve the above object, the present invention provides hydraulic oil temperature increase control for increasing the temperature of the hydraulic oil to a temperature increase value that is the temperature in a steady operating state at the start of operation of a machine. In the device, there is an actual temperature detection circuit that detects the temperature of the hydraulic oil, a means for setting and displaying the temperature rise value and all allowable values for this temperature rise value, and a startup circuit that detects the power supply start-up for starting machine operation. A detection circuit, a circuit that compares the allowable lower limit value obtained by subtracting the allowable value from the temperature rise value and the temperature of the hydraulic oil detected by the actual temperature detection circuit, and the output of this comparison circuit and the start-up detection circuit. The temperature increase signal generation circuit generates a signal for performing a temperature increase operation when the temperature of the hydraulic oil is lower than the allowable lower limit value when the power supply is started.

(Function) For example, when the temperature increase value is 40 to 50 degrees Celsius, the temperature of the hydraulic oil is managed using this value as the target value, but the actual temperature of the hydraulic oil is lowered by, for example, 3 to 5 degrees Celsius from the above temperature increase value. However, it will not have any negative effect on the control accuracy of oil field production. Furthermore, the temperature of the hydraulic oil does not drop suddenly even if the machine is completely stopped. Therefore, in the above setting/display means,
If all the temperature rise values and allowable values are set as described above, and the machine is completely stopped for a relatively short period of time, the temperature drop of the hydraulic oil will be within the above allowable values and no temperature rise signal will be issued. You can start regular operation immediately. In addition, the downtime is relatively long,
A heating operation is carried out only if the temperature falls outside the permissible value by a relatively large amount.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

10 is a hydraulically driven injection molding machine, and its mouth is a tank. 1
0 is a mold opening/closing drive unit, 13 is an injection drive unit, and these are driven by the hydraulic oil 14 supplied from the tank 11. 0 is a hydraulic oil temperature rising circuit, and 21 is a pump. , 22 is an electromagnetic switching valve, 3 is a flow path resistance serving as a heat generating part, and 24 is a +717-7 valve. This hydraulic oil temperature rising circuit 20 is shown conceptually in its basic structure, and in reality, all the hydraulic operating circuits of the mold opening/closing drive section 1 and the injection drive section 3 are referred to as the hydraulic oil temperature rising circuit O. is preferred.

A temperature sensor 31 is attached to the tank 11 to detect the temperature of the hydraulic oil 14 therein.

An A/D converter 32 and a linearizer 33 are connected to the temperature sensor 31, and the hydraulic oil 14 (hereinafter referred to as
Actual temperature detection circuit 3 that outputs TK digital (referred to as actual temperature)
It constitutes 0.

34 is a setting/display means for setting and displaying a temperature rise value T, which is the temperature of the hydraulic oil 14 in a steady operating state of the hydraulically driven injection molding machine 10, and an allowable value a therefor; Select ``No'' to configure and display the settings. This setting/displaying means 34 is configured to provide an allowable lower limit value 1'I'-a)k which is obtained by subtracting the allowable value af from the temperature increase value T to the 10,000 input section of the comparator circuit 35.

The comparator circuit 35 receives the allowable lower limit value (T-a) and the actual temperature t, determines whether or not the actual temperature t is lower than the allowable lower limit value (T-a), and uses the determination signal to increase the temperature. Signal generation circuit 3
It is designed to be given to 6.

Reference numeral 37 denotes a start-up detection circuit, which detects when the power source (not shown) is fully activated in order to start operation of the hydraulically driven injection molding machine 10, and sends a start-up signal to the temperature increase signal generation circuit 36. It is supposed to give you a lot of money.

When the temperature rise signal generation circuit 36 is given the rise signal, the temperature rise signal generation circuit 36 outputs the driver signal only if the comparison circuit 35 has given a determination signal indicating that the actual temperature t is lower than the allowable lower limit value (T-a). 38, and when the actual temperature t is equal to or higher than the allowable lower limit value (T-al), the temperature increase signal is not issued and operation can be started immediately.

The driver 38 is provided with a temperature increase operation selection signal for selecting whether or not the temperature increase operation is necessary from the setting/display means 34, and when this signal indicates that the temperature increase operation is "required", When the temperature increase signal is given, the hydraulic oil temperature increase circuit
The electromagnetic switching valve 2 is switched so that the oil discharged from the pump 21, which is activated when the power source is turned on, is supplied to the flow path resistor 3, which is a heat generating section. Note that the driver 38
A separate temperature sensor (not shown) is used to continue the above-mentioned temperature raising operation at the case where the temperature of the hydraulic oil 4 reaches the temperature raising value T.

Next, the operation of this device will be explained. Before we begin, a temperature increase value 1' and an allowable value a2 are set in the setting/display means 34. The temperature increase value T is usually 40 to 50°C, and the allowable value a varies depending on the operational control accuracy determined by the molding conditions of the hydraulically driven injection molding machine 10, but it ensures relatively high operational control accuracy. Therefore, it is preferable to set the temperature within 3 to 5°C.

Furthermore, the selection of whether or not the temperature raising operation is necessary is also related to the value of the allowable value a, but is determined according to the required operational control accuracy.

The actual temperature t of the hydraulic oil 14 decreases to near room temperature when the operation is stopped for a long time. When the power is turned on to start operation in this state, the actual temperature t given from the actual temperature detection circuit 30 to the comparison circuits 35, , S is the allowable lower limit value given to the comparison circuit 35 from the setting/display means 34. FT
-a) The processing is low, and the discrimination signal representing this is sent to the comparison circuit 35.
Since the temperature rise signal is applied to the temperature rise signal generation circuit 36 from the temperature rise signal generation circuit 36, the temperature rise signal is applied to the driver 38 by the temperature rise signal generation circuit 36 and the rise signal from the rise detection circuit 37. At this time,
Temperature raising operation required from setting/display means 34 to driver 38
When the command is issued, the driver 38 switches the electromagnetic switching valve 22 of the hydraulic oil temperature raising circuit 20, and passes the hydraulic oil 14 through the flow path resistor 23, which is a heat generating part, and raises the actual temperature tl until it reaches the temperature raising value T. let

On the other hand, when the power is turned on to restart after the entire operation has stopped for a relatively short period of time, if the actual temperature t remains at a value that is equal to or even higher than the allowable lower limit value (T-a), Even if the temperature rise signal generation circuit 36 receives a rise signal from the rise detection circuit 37, it does not give the temperature rise signal to the driver 38, thereby omitting the temperature rise operation entirely.

〔Effect of the invention〕

As described above, according to the present invention, the temperature of the hydraulic oil is detected at the start of operation, and the temperature increase operation can be performed only when the temperature drop is below the allowable value, thereby controlling the oil field production equipment. The operation of raising the temperature of the hydraulic oil can be suppressed to the necessary minimum without substantially causing any defects, thereby achieving the effect of enabling more efficient operation.

[Brief explanation of drawings]

The figure is a schematic diagram of a hydraulic operating system and a control system showing one embodiment of the present invention. 0...Hydraulic driven injection molding machine,...Tank, 12...Mold opening/closing drive unit, 3...Injection drive unit, 14...Hydraulic oil, 20...Hydraulic oil temperature rising circuit, 21...Pump, 22...Solenoid switching valve, 23...
Flow path resistance (heat generating part), 24... Relief valve, 30... Actual temperature detection circuit, 34... Setting/display means, 35... Comparison circuit, 36... Temperature increase signal generation circuit, 37...startup detection circuit, 3 and...driver. Ryo Ganto Toshiba Machine Co., Ltd.

Claims (1)

[Claims] A hydraulic oil temperature increase control device for raising the temperature of hydraulic oil to a temperature increase value that is a temperature in a steady operation state at the start of operation of a machine, the device includes: an actual temperature detection circuit that detects the temperature of the hydraulic oil; means for setting and displaying a value and an allowable value for the same temperature rise value; a start-up detection circuit that detects power-up for starting operation of the machine; and an allowable lower limit value obtained by subtracting the allowable value from the temperature rise value. and the temperature of the hydraulic oil detected by the actual temperature detection circuit, and the outputs of the comparison circuit and the start-up detection circuit are respectively given, so that the temperature of the hydraulic oil is within the allowable range when the power supply is turned on. A hydraulic oil temperature increase control device comprising: a temperature increase signal generation circuit that generates a signal for performing a temperature increase operation when the temperature is lower than a lower limit value.