An operation control device for a working vehicle comprises a hydraulic actuator to drive the hydraulic working device, operating oil supply source for driving the hydraulic actuator, an operating oil supply control device that performs control to supply operating oil to the hydraulic actuator, an operating device to be operated to make the hydraulic actuator work and a working gain setting device that sets a gain of working speed of the hydraulic actuator corresponding to the operation of the operating device. The operating oil supply control device controls operating oil supply from the operating oil supply source to the hydraulic actuator based on the operation output signal from the operating device and the working speed gain set by the working gain setting device.

In a method for operating a hydraulic device for providing a supply to hydraulic consumers (V) on a plastics injection moulding machine, provision is made of a pump (10) with a volumetric delivery characteristic that results in cyclic pulsations and of a servomotor (11) with multiple poles that result in cyclic pulsations. The pressure at the hydraulic consumer (V) is detected and is input as an actual value into a pressure regulator (13) that readjusts the servomotor (11), on the basis of a predefined pressure profile, to a pressure setpoint value at the hydraulic consumer (V). The cyclic pressure pulsation is minimized in that, by means of a rotational angle sensor (20), the rotational angle (φ) of the pump (10) and/or of the servomotor (11) is detected and correlated with the cyclic pulsations, and in that, from this, a corrective value or a corrective function is determined and is transmitted to the pressure regulator (13) with control subordinate to the regulation of the pressure setpoint value. Alternatively or in addition, this is achieved in the case of a hydraulic device also in that, as corrective means for the pressure regulation, said means being subordinate to the consideration of the pulsations, the number of components of the pump (10) that result in the cyclic pulsations and the number of components of the servomotor (11) that generate cyclic pulsations are equal, or one is a multiple of the other.

In a method for operating a hydraulic device for providing a supply to hydraulic consumers (V) on a plastics injection moulding machine, provision is made of a pump (10) with a volumetric delivery characteristic that results in cyclic pulsations and of a servomotor (11) with multiple poles that result in cyclic pulsations. The pressure at the hydraulic consumer (V) is detected and is input as an actual value into a pressure regulator (13) that readjusts the servomotor (11), on the basis of a predefined pressure profile, to a pressure setpoint value at the hydraulic consumer (V). The cyclic pressure pulsation is minimized in that, by means of a rotational angle sensor (20), the rotational angle (φ) of the pump (10) and/or of the servomotor (11) is detected and correlated with the cyclic pulsations, and in that, from this, a corrective value or a corrective function is determined and is transmitted to the pressure regulator (13) with control subordinate to the regulation of the pressure setpoint value. Alternatively or in addition, this is achieved in the case of a hydraulic device also in that, as corrective means for the pressure regulation, said means being subordinate to the consideration of the pulsations, the number of components of the pump (10) that result in the cyclic pulsations and the number of components of the servomotor (11) that generate cyclic pulsations are equal, or one is a multiple of the other.

A lifting mechanism has a descending mode including an energy-regeneration mode and a non-energy-regeneration mode. The lifting mechanism includes: a battery, an electric machine, a hydraulic pump, an oil tank, a hydraulic cylinder, a work platform and a flow limiting valve. In the energy-regeneration mode, the hydraulic fluid drives the hydraulic pump to operate as a hydraulic motor, thus in turn driving the electric machine to operate as a generator and charge the battery. In the non-energy-regeneration mode, the flow limiting valve limits the maximum of the descending speed of the work platform. In the present application, the flow limiting valve is used to provide throttling resistance to limit the maximum of the descending speed of the hydraulic fluid, thus in turn defining the maximum of the descending speed of the work platform. Therefore, in the present application, by using the flow limiting valve to define the maximum of the descending speed of the work platform, the safety problem due to an accelerated descent during descending of the work platform may be solved, and thus the safety of the lifting mechanism may be ensured.

A lifting mechanism has a descending mode including an energy-regeneration mode and a non-energy-regeneration mode. The lifting mechanism includes: a battery, an electric machine, a hydraulic pump, an oil tank, a hydraulic cylinder, a work platform and a flow limiting valve. In the energy-regeneration mode, the hydraulic fluid drives the hydraulic pump to operate as a hydraulic motor, thus in turn driving the electric machine to operate as a generator and charge the battery. In the non-energy-regeneration mode, the flow limiting valve limits the maximum of the descending speed of the work platform. In the present application, the flow limiting valve is used to provide throttling resistance to limit the maximum of the descending speed of the hydraulic fluid, thus in turn defining the maximum of the descending speed of the work platform. Therefore, in the present application, by using the flow limiting valve to define the maximum of the descending speed of the work platform, the safety problem due to an accelerated descent during descending of the work platform may be solved, and thus the safety of the lifting mechanism may be ensured.

The lifting mechanism includes a battery, an electric machine, a hydraulic pump, an oil tank, a hydraulic cylinder, a work platform and a proportional valve or switch valve. In the energy-regeneration mode, the hydraulic fluid drives the hydraulic pump to operate as a hydraulic motor, thus in turn driving the electric machine to operate as a generator and charge the battery. In the present application, the hydraulic pump operates to increase a pressure in a hydraulic line between the hydraulic pump and the proportional valve or switch valve before the proportional valve or switch valve is switched from a unidirectional communication position to a bidirectional communication position. When the proportional valve or switch valve is switched from the unidirectional communication position to the bidirectional communication position, by increasing the pressure in the hydraulic line, it could be avoided that the volume of hydraulic fluid has low pressure is compressed because the hydraulic fluid has low pressure is communicated with hydraulic fluid has high pressure; therefore a state of sudden drop of the work platform is avoided, and safety performance and operating experience of the lifting mechanism is improved.

The lifting mechanism includes a battery, an electric machine, a hydraulic pump, an oil tank, a hydraulic cylinder, a work platform and a proportional valve or switch valve. In the energy-regeneration mode, the hydraulic fluid drives the hydraulic pump to operate as a hydraulic motor, thus in turn driving the electric machine to operate as a generator and charge the battery. In the present application, the hydraulic pump operates to increase a pressure in a hydraulic line between the hydraulic pump and the proportional valve or switch valve before the proportional valve or switch valve is switched from a unidirectional communication position to a bidirectional communication position. When the proportional valve or switch valve is switched from the unidirectional communication position to the bidirectional communication position, by increasing the pressure in the hydraulic line, it could be avoided that the volume of hydraulic fluid has low pressure is compressed because the hydraulic fluid has low pressure is communicated with hydraulic fluid has high pressure; therefore a state of sudden drop of the work platform is avoided, and safety performance and operating experience of the lifting mechanism is improved.

An electronic valve controller for an open-loop and closed-loop control of a valve island includes four or eight valve disks having pneumatic valves configured to perform a motion task. Applications for the open-loop and closed-loop control of the valve island can be loaded onto the electronic valve controller. The invention further relates to a valve assembly, which is controlled in an open-loop and closed-loop manner by an electronic valve controller, to a corresponding method, and to a system.

An electronic valve controller for an open-loop and closed-loop control of a valve island includes four or eight valve disks having pneumatic valves configured to perform a motion task. Applications for the open-loop and closed-loop control of the valve island can be loaded onto the electronic valve controller. The invention further relates to a valve assembly, which is controlled in an open-loop and closed-loop manner by an electronic valve controller, to a corresponding method, and to a system.

Presented is a system and method to control hydraulic fluid flow, more specifically throttle hydraulic fluid flow, to achieve actuator deceleration rates greater than the maximum deceleration rate of an electrically driven pump. Electric machines and electric machine inverters generally have a maximum torque and current limit beyond which they cannot be operated at. To decelerate a large inertia load for example, high electric machine torque and inverter current are required to provide the braking torque, opposing the fluid flow and pressure generated by the load and hydraulic system.