Energy-saving recovery device for servo hydraulic-electric control brake system of injection molding machine

Abstract

The utility model discloses an injection molding machine servo electro-hydraulic control brake system energy-saving recovery device, which comprises a servo controller and a servo motor, the input end of the servo controller is connected with an external power supply, the output end of the servo controller is connected with the servo motor, the servo controller is provided with a bus connecting end, the bus connecting end is connected with a brake energy-saving recovery unit, and the brake energy-saving recovery unit is connected with the servo motor. The brake energy-saving recovery unit is composed of a capacitor bank box, more than two capacitors with the same specification are connected in series in the capacitor bank box, and a voltage-sharing resistor is connected in parallel to each of the two ends of each capacitor. Electric energy generated in the braking and deceleration process is effectively utilized and stored through the capacitor for subsequent work operation, energy waste is reduced, meanwhile, an original braking unit, an original input filter and an original alternating-current reactor are omitted, cost is reduced, electromagnetic interference is effectively shielded through arrangement of the shielding box body, and the service life of the device is prolonged. The structure is simple, cost is low and work is stable.

Description

Technical Field

[0001] The utility model relates to the technical field of injection molding machine control brake system, in particular to an energy-saving recovery device for an injection molding machine servo hydraulic-electric control brake system. Background Art

[0002] The hydraulic and electric servo control system of injection molding machines has been widely used in the plastic processing industry. Due to the particularity of the injection molding process, the pressure and flow of the oil in the servo hydraulic special pump often need to change frequently during the injection molding process. The servo hydraulic special pump is controlled by a servo motor. Therefore, when the oil pressure and flow need to be reduced, the servo motor will instantly slow down or even stop during work. Since the speed of the servo motor is instantly reduced, a large amount of braking energy will be generated. This braking energy will cause the bus voltage in the servo control system to be too high, generally exceeding 720V. In order to protect the servo control components, a braking unit will be set at the bus end, and the braking unit will discharge and generate heat to the brake resistor to consume excessive energy. In order to prevent the harmonics caused by the servo motor from impacting the input power grid, an input filter and an AC reactor are installed between the input end of the servo control system and the external power grid to reduce the impact of harmonics on the power grid. At present, this method will cause energy waste and its cost is also high. Utility Model Content

[0003] The technical solution adopted by the utility model to solve the above technical problems is:

[0004] The energy-saving recovery device of the servo hydraulic-electric control brake system of an injection molding machine includes a servo controller and a servo motor. The input end of the servo controller is connected to an external power supply, and the output end thereof is connected to the servo motor. The servo controller is provided with a busbar connection end, and the busbar connection end is connected to a brake energy-saving recovery unit. The brake energy-saving recovery unit is composed of a capacitor group box, and two or more capacitors of the same specification are connected in series in the capacitor group box, and a voltage-equalizing resistor is connected in parallel at both ends of each capacitor.

[0005] Furthermore, the capacitor bank box is externally covered with a shielding box body made of stainless steel.

[0006] The beneficial effects of the utility model are: effectively utilizing the electrical energy generated during braking and deceleration, storing it through capacitors to provide subsequent work operations, reducing energy waste, while eliminating the original braking unit, input filter and AC inductor, and reducing costs. The setting of the shielding box effectively shields electromagnetic interference, and it has a simple structure, low cost and stable operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a structural schematic diagram of the utility model.

[0008] As shown in the figure: 1. Servo controller; 2. Capacitor group box; 3. Capacitor; 4. Voltage balancing resistor; 5. Operation panel; 6. Bus connection terminal. DETAILED DESCRIPTION

[0009] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0010] In the past, the servo hydraulic controller of the injection molding machine usually connected the brake unit to the bus connection end of the servo controller to consume the braking energy. The brake unit was connected to a brake resistor. When the servo motor braked, the electric energy generated by the brake flowed back to the bus of the servo controller through the output end of the servo controller, and then flowed to the brake resistor of the brake unit through the bus. The brake resistor heated up and consumed this part of the electric energy, so that the voltage of the bus would not increase due to the braking electric energy, thereby protecting the servo controller components. However, this method caused energy waste.

[0011] like Figure 1 As shown, an energy-saving recovery device for a servo hydraulic-electric control brake system of an injection molding machine includes a servo controller 1 and a servo motor. The input end of the servo controller 1 is connected to an external power supply to power it, and its output end is connected to the servo motor. The servo controller 1 has a busbar connection end 6, and the busbar connection end 6 is connected to a brake energy-saving recovery unit. The brake energy-saving recovery unit is composed of a capacitor group box 2. Two or more capacitors 3 of the same specification are connected in series in the capacitor group box 2 for storing excess electricity caused by the servo motor brake. A voltage-equalizing resistor 4 is connected in parallel at both ends of each capacitor 3 for averaging the voltage at both ends of each capacitor 3, thereby protecting the capacitor 3.

[0012] In order to shield electromagnetic interference and protect the safety of equipment and personnel, the capacitor bank box 2 is covered with a shielding box made of stainless steel.

[0013] The working principle is as follows: the servo controller 1 provides three-phase alternating current of different frequencies to the servo motor to drive it to work and rotate. The servo motor drives the servo hydraulic pump to change the pressure and flow of the oil. When the pressure and flow of the oil of the servo hydraulic pump are required to decrease during production, the servo controller 1 will control the servo motor to instantly reduce or stop its rotation speed. The braking process will generate a large amount of braking electric energy. This part of the energy is transmitted to the bus through the output end of the servo controller 1. The voltage of the bus increases, and then it is transmitted to the capacitor 3 in the brake energy-saving recovery unit through the bus connection end 6 and stored in the capacitor 3. The capacitor 3 is equivalent to a battery that can be charged and discharged. When the servo controller 1 controls the injection molding machine to perform the next work, power supply is required. At this time, the electric energy is first released from the capacitor 3 to the bus connection end 6. The electric energy is supplied to the servo motor through the bus and the output end of the servo controller 1 to work. When the electric energy in the capacitor 3 is continuously discharged and is not enough to maintain the voltage of the bus, it is powered by the external power supply at the input end of the servo controller 1.

[0014] Due to the setting of the brake energy-saving recovery unit, the harmonics caused by the brake power of the servo motor will not impact the external power grid, so there is no need to install an input filter and an AC reactor between the input end of the servo controller 1 and the external power grid, saving costs.

[0015] The present utility model is not limited to the above-mentioned optimal implementation mode. Any other products identical or similar to the present utility model derived by anyone under the inspiration of the present utility model shall fall within the protection scope of the present utility model.

Claims

1. An energy-saving recovery device for a servo hydraulic-electric controlled brake system of an injection molding machine, comprising a servo controller (1) and a servo motor, wherein the input end of the servo controller (1) is connected to an external power supply, and the output end thereof is connected to the servo motor, and the servo controller (1) has a busbar connection end (6), characterized in that: The busbar connection end (6) is connected to a brake energy-saving recovery unit, which is composed of a capacitor group box (2), in which two or more capacitors (3) of the same specification are connected in series, and a voltage-equalizing resistor (4) is connected in parallel at both ends of each capacitor (3).

2. The energy-saving recovery device for the servo hydraulic-electric control brake system of an injection molding machine according to claim 1 is characterized in that: The capacitor group box (2) is externally covered with a shielding box body made of stainless steel.

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