CN203900995U - Hydraulic balance circuit for gantry machining center - Google Patents

Abstract

The utility model discloses a hydraulic balance circuit of a gantry machining center, which comprises an oil tank, a liquid level gauge, an air cooler, a filter, an oil injector, a variable plunger pump, a drive motor, a one-way valve, an electromagnetic switch valve, a superposition type Counterbalance valves, electronic pressure relays, accumulators, balance cylinders, high pressure ball valves, pressure gauges and pressure gauge switches. This circuit uses an electronic pressure relay to detect the pressure in the pressure-holding circuit of the accumulator. The high and low working pressures set by the electronic pressure relay automatically control the power-off and power-on of the electromagnetic switch valve and the stop and start of the hydraulic pump. . The use of this circuit can ensure that the hydraulic balance cylinder always maintains a relatively stable balance hydraulic pressure, and avoid the short-term failure of the hydraulic balance function due to insufficient oil supply to the balance cylinder during the start-stop of the main shaft and the process of lifting and shifting. And it has the advantages of low cost, convenient adjustment, strong system reliability, high production quality and high efficiency.

Description

A hydraulic balance circuit of a gantry machining center

technical field

The utility model relates to a control circuit of a hydraulic balance device for a spindle box part of a gantry machining center, in particular to a hydraulic balance circuit of a gantry machining center.

Background technique

The gantry machining center belongs to heavy machinery, and the spindle box is one of its important components. Usually, the spindle box is equipped with an automatic balance system, which can dynamically balance the self-weight of the spindle box to ensure the machining accuracy of the machine tool. At present, the automatic balance system of the spindle box of the gantry machining center usually adopts two methods of double screw drive balance and double hydraulic cylinder balance.

The use of double lead screws to drive the balancing device has high manufacturing costs and high requirements for mechanical design and installation. However, the gantry machining center equipped with hydraulic balance oil cylinder has the phenomenon that the pressure of the hydraulic system decreases rapidly when the headstock is raised and started, and the system pressure increases when the headstock is lowered and started during use. The reason for the decrease in pressure is insufficient oil supply, or the start-up speed of the hydraulic cylinder cannot keep up with the start-up speed of the spindle drive motor, which causes the load of the spindle screw drive motor to increase instantaneously during the lifting and start-up stage of the spindle box, and the surface processing quality of the parts is not good. Ideal and other issues.

Contents of the invention

In view of the shortcomings of the above-mentioned gantry machining center, the purpose of this utility model is: to provide a hydraulic balance circuit of the gantry machining center, to avoid the phenomenon of instantaneous increase in the motor load driving the spindle due to undervoltage or pressure fluctuations, and to ensure the improvement of production quality and work efficiency.

The technical solution of the utility model to achieve the above purpose is: a hydraulic balance circuit of a gantry machining center, including an oil tank, a filter, a variable plunger pump and a balance oil cylinder rigidly connected with the headstock parts, which are arranged in sequence. The replenishment end of the fuel tank is connected to the oil injector beside the filter, and the variable displacement plunger pump is externally connected to the drive motor. It is characterized in that: the hydraulic balance circuit is equipped with an accumulator, an electronic A pressure maintaining unit composed of a pressure relay, an electromagnetic switch valve and a superimposed counterbalancing valve for adjusting hydraulic oil pressure. The electromagnet YA of the switch valve is connected to the electronic pressure relay for controlled on-off.

Further, a one-way valve for checking oil to the variable displacement plunger pump is provided between the variable displacement plunger pump and the electromagnetic switch valve.

Further, a high-pressure ball valve is provided on the oil circuit between the accumulator and the balance oil cylinder.

Further, the pressure holding unit is provided with a pressure gauge and a pressure gauge switch.

Further, the oil tank is provided with a liquid level gauge.

Furthermore, an air cooler is provided between the variable displacement plunger pump and the oil tank.

After the above-mentioned technical scheme of the utility model is applied and implemented, its remarkable advantages are reflected in: the working pressure of the hydraulic balance oil cylinder is automatically regulated by using the accumulator with the help of control valves such as superimposed counterbalancing valves, electronic pressure relays and electromagnetic switch valves, ensuring that the spindle box is During sudden changes in speed such as start-up and lifting, the hydraulic oil pressure and the self-weight of the main shaft box components are fully utilized to balance the role, avoiding the phenomenon of instantaneous increase in the motor load driving the main shaft due to undervoltage or pressure fluctuations, and ensuring the improvement of production quality and work efficiency. In addition, the hydraulic balance circuit automatically controls the hydraulic pump to be in a non-working state during the stable working stage of the balance cylinder, which is conducive to saving energy consumption and reducing heat generation; and the circuit is easy to install and adjust, with a high degree of automation and low cost.

Description of drawings

Fig. 1 is the structure and working principle diagram of the hydraulic balance circuit of the gantry machining center of the present invention.

Detailed ways

The purpose and advantages of the utility model will be shown in detail through the following preferred embodiments in conjunction with the non-restrictive description of the accompanying drawings. This embodiment is only a typical example of the application of the utility model technical solution. The resulting implementations all fall within the scope of protection required by the utility model.

From the point of view of the existing hydraulic balance circuit of the gantry machining center, it mainly and necessary includes oil tanks, filters, variable plunger pumps and balance oil cylinders rigidly connected with headstock components; the supply end of the oil tank 1 is in An oil injector is connected beside the filter, and the variable displacement plunger pump is externally connected with a drive motor. The utility model proposes an improvement scheme aiming at the shortcomings of the hydraulic balance circuit, so as to improve the working pressure stability of the balance oil cylinder. Its special feature is that there is a pressure maintaining unit composed of an accumulator, an electronic pressure relay, an electromagnetic switch valve and a superimposed counterbalancing valve for adjusting the hydraulic oil pressure between the balance oil cylinder and the variable displacement plunger pump. The above electronic pressure relay It is installed on the inlet side of the balance oil cylinder and has preset upper and lower limit values of working pressure. The electromagnet YA of the above-mentioned electromagnetic switch valve is connected to the electronic pressure relay for controlled on-off.

As a further optimization of the above-mentioned necessary scheme, a one-way valve is provided between the variable displacement plunger pump and the electromagnetic switch valve to check oil back to the variable displacement plunger pump; High pressure ball valve. In addition, the pressure holding unit is provided with a pressure gauge and its pressure gauge switch; the fuel tank is provided with a liquid level gauge; and the variable plunger pump and the fuel tank are provided with an air cooler.

As shown in Figure 1, it is a preferred embodiment of the hydraulic balance circuit of the gantry machining center of the present invention, which includes an oil tank 1 connected as shown in the figure, a liquid level gauge 2, an air cooler 3, a filter 4, and an oil injector 5 , variable plunger pump 6, drive motor 7, one-way valve 8, electromagnetic switch valve 9, superimposed counterbalance valve 10, electronic pressure relay 11, accumulator 12, first balance cylinder 13, second balance cylinder 14, high pressure Ball valve 15, pressure gauge 16 and pressure gauge switch 17. From the perspective of the functions of each part of the components: the oil tank 1 is used to store hydraulic oil, the liquid level gauge 2 is used to measure the liquid level in the oil tank, the air cooler 3 is used to cool the temperature of the circulating fluid oil, and the filter 4 is used to connect in series The oil suction line of the hydraulic pump (that is, the variable plunger pump) plays the role of filtering liquid oil, the oil injector 5 is used to refuel the oil tank, the variable plunger pump 6 is used to provide pressure oil to the hydraulic balance system, and the drive motor 7 is used to drive The hydraulic pump is running, the one-way valve 8 is used to prevent the backflow of liquid oil and protect the hydraulic pump, the electromagnetic switch valve 9 is used to automatically control the on-off of the oil supply circuit, the superimposed counterbalance valve 10 is used to adjust the hydraulic pressure of the balance cylinder, and the electronic pressure relay 11 It is used to convert the measured hydraulic signal into an electrical signal, control the on-off of the electromagnetic switch valve and the start and stop of the hydraulic pump drive motor. The bladder accumulator 12 is used to store and maintain hydraulic oil with a certain pressure value. Two balance oil cylinders It is used for rigid connection with the headstock parts, and the hydraulic force in the balance oil cylinder is used to balance the weight of the headstock parts. The high-pressure ball valve 15 is used to control the opening and closing of the channel between the hydraulic oil and the accumulator in the system. The pressure gauge 16 It is used to measure the working pressure of the hydraulic oil, and the pressure gauge switch 17 is used to control whether the pressure gauge reads.

From the perspective of oil supply, the oil suction port of the hydraulic pump 6 is connected to the filter 4. When the drive motor 7 is energized, the hydraulic pump 6 is driven to run. When the electromagnet YA is energized, the hydraulic pump outputs pressure oil to the two balance oil cylinders and the accumulator, the oil supply pressure is adjusted by the superimposed counterbalance valve 10, and the pressure gauge 16 measures the pressure value at the inlet of the balance oil cylinder.

In particular, since the electronic pressure relay 11 sets two working pressure limits, high and low, when the working pressure of the balance cylinder is lower than the lower limit (lower value) set by the electronic pressure relay 11, the hydraulic pump is controlled to start, After a delay of 2-4 seconds, the electromagnet YA is energized, and the hydraulic pump supplies pressure hydraulic oil to the balance cylinder and accumulator; when the working pressure of the balance cylinder is higher than the upper limit (high value) set by the electronic pressure relay 11 , the control electromagnet YA is powered off, the hydraulic pump stops running after a delay of 2-4 seconds, and the hydraulic pump stops supplying pressure oil to the accumulator. When the working pressure of the balance cylinder is within the value range set by the electronic pressure switch 11, the piston rod in the hydraulic balance cylinder rises and falls synchronously with the movement parts of the headstock. When the headstock parts drive the piston rod to move upward, the bladder accumulator 11 will expand due to the pressure drop, and the compressed gas in the bag will expand, and then the hydraulic pressure will enter the circuit to supply oil to the hydraulic balance cylinder; when the headstock parts drive the piston rod down During exercise, due to the increase in pressure, the oil enters the capsule accumulator, and the gas in the capsule is compressed.

It can be seen that this circuit adopts the accumulator hydraulic balance device, and with the help of control valves such as superimposed counterbalance valve, electronic pressure relay and electromagnetic switch valve, the working pressure of the hydraulic balance cylinder is automatically adjusted to ensure that the spindle box is in the process of starting, lifting and other speed mutations. In this process, the hydraulic pressure and the self-weight of the headstock components are fully utilized to balance the effect, avoiding the phenomenon of instantaneous increase in the load of the motor driving the spindle due to undervoltage or pressure fluctuations, and ensuring the improvement of production quality and work efficiency. The hydraulic balance circuit automatically controls the hydraulic pump to be in a non-working state during the stable working stage of the balance cylinder, which helps to save energy consumption and reduce heat generation. The utility model has the advantages of convenient installation and adjustment, high degree of automation and low cost.

Claims (6)

1. the Hydraulic Balancing Circuit of a gantry machining center, comprise the fuel tank of establishing in order, filter, Variable plunger pump and with the rigidly connected balancing cylinder of spindle box part, the supply end of described fuel tank connects oil syringe at filter side, the external drive motors of described Variable plunger pump, it is characterized in that: described Hydraulic Balancing Circuit is provided with by accumulator between balancing cylinder and Variable plunger pump, electronic pressure relay, the superposing type of electromagnetic switch valve and regulator solution oil pressure contend with valve form pressurize unit, described electronic pressure relay is located at the inlet side of balancing cylinder and is had in default operating pressure, lower limit, the electromagnet YA of described electromagnetic switch valve is connected to the controlled break-make of electronic pressure relay.

2. the Hydraulic Balancing Circuit of gantry machining center according to claim 1, is characterized in that: between described Variable plunger pump and electromagnetic switch valve, be provided with to the check valve of Variable plunger pump non-return fluid.

3. the Hydraulic Balancing Circuit of gantry machining center according to claim 1, is characterized in that: on the oil circuit between described accumulator and balancing cylinder, be provided with high-pressure ball valve.

4. the Hydraulic Balancing Circuit of gantry machining center according to claim 1, is characterized in that: described pressurize unit is provided with Pressure gauge and pressure meter switch thereof.

5. the Hydraulic Balancing Circuit of gantry machining center according to claim 1, is characterized in that: described fuel tank is provided with liquid level gauge.

6. the Hydraulic Balancing Circuit of gantry machining center according to claim 1, is characterized in that: between described Variable plunger pump and fuel tank, be provided with forced air cooler.