34results about How to "Good fretting" patented technology

The invention relates to a vehicle crane control method and device, and a vehicle crane. The method comprises the following steps of determining a voltage target value according to a received input signal for starting a crane from a control handle; determining an intermediate voltage value according to a first voltage value and the voltage target value; and when each signal output time point of afirst control time period is reached, determining and outputting a first output voltage corresponding to the signal output time point, wherein the first output voltage at a first target time point isthe intermediate voltage value, the first output voltage of a time end point of a first control time period is a voltage target value, and in the first time period formed by a time starting point of the first control time period and the first target time point, an increasing amplitude of the first output voltage corresponding to a latter signal output time point is increased along with the increase of time compared with the increasing amplitude of the first output voltage corresponding to a former signal output time point. Therefore, good micro-motion performance is achieved on control of thecrane, and large shaking in a starting process is prevented.

The invention discloses a confluence control device of a hydraulic crane. The pilot-operated hydraulic control mode and the proportional electromagnetic valve pilot control mode are adopted for controlling confluence and flow on the two sides. Connection of a confluence device is decided by the one, with higher pressure, of a hydraulic control pilot oil channel and an electric proportion control pilot oil channel, and the combined work flow of the left side and the right side is decided by the continuous change condition of the deflection angle of a pilot handle or the pressure condition on the two sides of a system. Left-to-right confluence or right-to-left confluence is selected according to the pressure flow requirement of systems on the two sides of combined confluence. Confluence impact generated when the crane acts is reduced by controlling moving of a confluence valve core. According to the invention, impact generated in the confluence process of a main hydraulic valve of the crane is reduced, the confluence process can be controlled, the micro-motion property in the process of winching small flow by the crane is guaranteed, and the confluence process can be smooth; by adopting the electronic control confluence mode, the feasibility performance of confluence is improved, and the requirements of hydraulic actuating mechanisms of engineering machinery for hydraulic system confluence on different work conditions can be met.

The invention provides a load-sensitive multiway valve with a micromotion valve element. The load-sensitive multiway valve with the micromotion valve element comprises at least one valve body, wherein the valve body is provided with one group or multiple groups of valve blocks and an oil inlet hole; two ends of the valve body are respectively provided with a control end cover and a control piston end cover; each valve block comprises a main valve element hole, a micromotion valve element hole, a compensation valve element hole, an oil inlet path, a multiway valve oil inlet cavity, a plurality of oil outlet holes and oil leakage holes; a main valve element, a micromotion valve element and a compensation valve element are respectively installed in each main valve element hole, each micromotion valve element hole and each compensation valve element hole; each he oil inlet path is communicated with the corresponding oil inlet hole of the valve body and is communicated with a multiway valve oil inlet cavity via the corresponding compensation valve element hole; each multiway valve oil inlet cavities are communicated with the oil outlet holes and the oil leakage holes via the main valve element holes and the micromotion valve element holes. The load-sensitive multiway valve is provided with the micromotion valve elements, so that the load-sensitive multiway valve has the advantages of better multiway valve micromotion performance and convenience in the small-flow regulation of a system, system pressure loss is reduced, and an energy use ratio is improved. According to the load-sensitive multiway valve, the processing of a valve element throttling groove is reduced, and the difficulty of a processing technology is lowered.

The invention discloses a rotary buffer valve used in a hydraulic system of a crane. It includes a valve body with two main oil passages. The valve body also has a pilot control oil port a, a pilot control oil port b, an oil inlet P, an oil return port T, an oil drain port L and a rotary motor connected to the oil inlet and outlet. The oil port A and oil port B of the port; the valve body is mainly equipped with a three-position six-way hydraulic control reversing valve, a main relief valve and a free-slip solenoid valve; two main oil passages leading to A and B oil ports Each is equipped with an adjustable back pressure valve; there is a throttling oil passage connecting the two main oil passages between the two main oil passages, and the intersection point of the throttling oil passage and the main oil passage is more Closer to port A and port B. The invention has the advantages of compact structure, small volume, low cost, convenient installation and operation, strong adaptability, wide application, good fretting performance, precise rotary positioning and stable stop.

The invention relates to the technical field of engineering machinery, and discloses a hydraulic transmission system and a crane. The hydraulic transmission system includes a main control oil circuit and an auxiliary control oil circuit; the main control oil circuit includes a first power unit (1) and an execution unit and is connected between the first power unit (1) and the execution unit The first control module (2) used to control the action of the execution unit; the hydraulic oil output from the auxiliary control oil circuit can merge with the hydraulic oil output from the first control module (2) to control the execution unit. The hydraulic transmission system can not only ensure that the equipment using the hydraulic transmission system has good micro-movement performance under heavy load, but also meet the high-speed requirements under light load and no load, and can save costs.

The invention discloses a combined-type multi-way reversing valve for a coal-mine full-hydraulic underground drilling machine. The combined-type multi-way reversing valve consists of an oil feeding valve body, a motor direction control valve body, a motor rotating-speed control valve body, an auxiliary control valve body, an oil cylinder direction and speed control valve body, a hydraulic chuck control valve body, a gripper control valve body and a hydraulic chuck oil return valve body which are communicated in sequence. The combined-type multi-way reversing valve has the advantages that since the original hydraulic oil pipe is replaced by an oil path block, the oil path is shortened, and leaking points possibly existing on the oil path are reduced; all the valve bodies are integrated into one valve block, the structure is more compact, the stroke of hydraulic oil is short, the pressure and power loss is less, the micro-motion performance is good, and the accuracy is high, the system efficiency is high; and all hydraulic elements are arranged orderly, concentrated control is easy to implement, the operation is convenient, and the reliability of a main machine is good.

The invention provides an installation apparatus for bird driving device which comprises a base, a horizontally moving mechanism, a longitudinally moving mechanism, a multi-stage elevation oil cylinder and a positioning device. Four walking wheels are arranged under the base; a U type groove is provided in the central position of the base back end. Both the horizontally moving mechanism and the longitudinally moving mechanism adopt a screw drive principle. And longitudinally moving mechanism is mounted on the sliding block of the horizontally moving mechanism; the multistage elevation oil cylinder is arranged on the sliding block of the longitudinally moving mechanism. The positioning device is arranged on the top of the multistage elevation oil cylinder. The apparatus, with a simple structure, is convenient to operate. With the apparatus, it is possible to install a bird driving device without having to cut off power supply or climbing a rod. This not only reduces the labor intensity, but also improves the safety of installation of a bird driving device.

The invention relates to a fixed jib stepless variable amplitude control system for a crane and the crane. The control system includes an electric proportional pressure reducing valve, a variable pump, a first reversing valve and a hydraulic oil cylinder for making the fixed jib variable amplitude; A reversing valve is located on the oil circuit between the variable pump and the hydraulic cylinder, the pressure oil output by the variable pump enters the hydraulic cylinder through the first reversing valve, and the electric proportional pressure reducing valve controls the displacement of the output pressure oil of the variable pump. The fixed jib stepless variable amplitude control system for a crane provided by the invention utilizes an electric proportional pressure reducing valve to control the displacement of a variable pump, realizes continuous variation of the displacement of the variable pump, has a wide speed regulation range, and has good fretting performance.

The invention discloses a motor-driven hydraulic system for a crane amplitude changing mechanism and an action method thereof, and belongs to the field of construction machinery. The motor-driven hydraulic system comprises an electric driving device and a hydraulic device; a battery supplies power to a controller, the controller adjusts the rotation direction and rotating speed of an electromotor,the electromotor drives a hydraulic motor, and when the hydraulic motor reversely drags the electromotor, the electric driving device can achieve the reversing drag power generation energy recovery;when the amplitude is increased, the electromotor rotates forward to drive the motor, pressure oil is output to be supplied to a rodless cavity of a hydraulic cylinder, a piston rod extends out, and the electricity energy is converted into the gravitational potential energy in the process; and when the amplitude in decreased, the electromotor rotates reversely, the pressure oil of the rodless cavity of the hydraulic cylinder drives the electromotor through the hydraulic motor, the electromotor is in a reversing drag power generation condition, the generated electric energy is stored in the battery, and the energy can be reused when the amplitude is increased. According to the motor-driven hydraulic system, the gravitational potential energy of a jib and the sling load is recovered and utilized when the amplitude is decreased, the energy consumption can be significantly lowered, the system efficiency is improved, and the heating is reduced.

The present invention provides a steel pile column full-automatic verticality regulation and control system and its method. Its method includes the following steps: (1) making verticality measurement of steel pile column by using measuring device; (2) transferring measured data into measurement system computer; (3). measuring system computer can be used for calculating and analyzing said data; (4). transferring said result into the hydraulic system cmputer by means of measurement system computer; (5) hydraulic system can be used for correcting position under the control of hydraulic system computer; and (6). judging that the above-mentioned corrected position is in place or not, if it is not in place, returning step (2). Said system is high in accuracy, smooth and stable in operation, good in micromotion property and can implement step-by-step operation less than 0.2 mm.