A kind of active control hydraulic servo buffer
Technical field
The present invention relates to a kind of hydraulic bjuffer, particularly servo-controlled hydraulic bjuffer.
Background technology
A present hydraulic bjuffer part is to be combined together hydraulic jack and mechanical spring, what buffer was compressed
Process is the process done work by piston press fluid.This process consumes a large amount of kinetic energy, plays cushioning effect.When having worked
Finish, the piston spring that is reset is pushed into home position, completes a working cycle process.The response time of this hydraulic bjuffer
Long, control accuracy is low, recovery time length, and can not control the hydraulic oil liquid pressure after buffering, it is impossible to meets high-precision, fast ring
Answer the requirement of vibration damping occasion.Another buffer is that servo spool is integrated into hydraulic cylinder, and the molar behavior of hydraulic cylinder passes through machine
Tool structure realizes that the response of the buffering of this phase buffer is fast, and precision is high, but still can not realize the alone cycle of fluid, it is necessary to
Artificial and mechanical assistance, while the linear motion of hydraulic cylinder is converted into the complicated mechanical structure of curvilinear motion needs.
The present high occasion of some control accuracy requirements requires when load shedding:No more than 0.2s's during system overload
By load reduction in time, but acceleration is converted into order to which the requirement of some functions of system also needs to fractional load, dropped simultaneously
The position of the load shedding bearing piece of loading system is curvilinear motion, is to be in diverse location in overload and normal condition, existing buffering
Device is difficult the action request for meeting system.
The content of the invention
It can meet that response is fast it is an object of the invention to provide one kind, realize automatic cycle with pure hydraulic way, automatically control
Precision is high, the linear motion of hydraulic cylinder independently can be converted into curvilinear motion, active control hydraulic servo simple in construction buffering
Device.
The invention mainly comprises:Low pressure accumulator, motor, hydraulic pressure constant displacement pump, check valve, hydraulic efficiency servo-valve, hydraulic cylinder,
Displacement transducer, pressure sensor, servo amplifier and safety valve.Wherein, the low pressure accumulator and switch valve phase as fuel tank
Even, carry out oil-filled by the switch valve and drain the oil.The low pressure accumulator is connected with the hydraulic pressure constant displacement pump equipped with motor, the liquid
Pressure constant displacement pump is connected with check valve inlet, and the outlet of the check valve is connected with the oil inlet of hydraulic efficiency servo-valve, and hydraulic efficiency servo-valve returns
Hydraulic fluid port is connected with low pressure accumulator outlet.The outlet of check valve is connected with safe valve inlet, and safety valve is direct acting type overflow valve, peace
Full valve exports to be connected with low pressure accumulator outlet, system can be made safely to run.The hydraulic efficiency servo-valve is to respond fast, precision
High three-position four-way hydraulic servo valve, which is provided with hydraulic servo amplifier be used for buffer after holding pressure control, and watched by hydraulic pressure
Take reciprocating motion and hydraulic control that hydraulic cylinder is realized in valve commutation.Two interfaces of the hydraulic efficiency servo-valve oil-out respectively with by two
Two oil inlets of the hydraulic lock of individual hydraulic control one-way valve composition are connected, and the oil-out of hydraulic lock is respectively with hydraulic cylinder rodless cavity and having
Rod cavity is connected, and the pipeline that wherein hydraulic lock is connected with rodless cavity is provided with pressure sensor.Hydraulic lock can make hydraulic efficiency servo-valve
Avoid, by how unnecessary compression shock, effectively protecting hydraulic efficiency servo-valve.Position is provided with piston rod in hydraulic cylinder
Displacement sensor, after the piston of hydraulic cylinder reaches specified location, the signal detected is then delivered to servo and put by displacement transducer
Big device, and then control the switch of servo valve.The outer end of hydraulic cylinder piston rod is hinged by ball pivot and sliding block, and sliding block is located at right with it
On the guide rail answered, so as to which the linear motion of hydraulic cylinder is converted into required curvilinear motion, buffering and the basic fortune of pressurize are realized
It is dynamic.The length of guide rail is determined according to the stroke of hydraulic cylinder and the corner of circular motion, and the position-limit mechanism of sliding block is set at guide rail both ends.
The present invention has the following advantages that compared with prior art:
(1) present invention realizes the straight line of hydraulic cylinder with other hydraulic bjuffer structure compareds simply by the form of pure hydraulic pressure
Motion is converted into the curvilinear motion of load shedding bearing piece, and can realize the reciprocating motion automatically controlled so that load shedding system
Load shedding bearing piece position can automatically control, and not interfere with state of system when overload is not subject to.
(2) response time of Normal hydraulic buffer is 3s or so, and pressure controling precision is 4% or so, the hydraulic cushion
The response time of device is 0.16s or so, and pressure controling precision is 2% or so.The present invention responds compared with Normal hydraulic buffer
It hurry up, precision is high, automatically controls precision height, simple in construction,.
(3) present invention is easy to control compared with other hydraulic bjuffers, can be by specified portions load transfer into system
Acceleration or some specified functions, while this specified portions can control at any time as needed, realize some specific conditions
It is required that.
(4) pressure sensor of the invention is arranged on hydraulic cylinder rodless cavity, and displacement transducer is installed on the piston rod, safety
Valve and auxiliary check valve and pump and motor all integrate, and final cylinder and fuel tank all integrate so that compact-sized.
Brief description of the drawings
Fig. 1 is the hydraulic schematic diagram of the present invention;
Fig. 2 is that hydraulic part of the present invention and mechanical part are hinged schematic diagram.
In figure:1st, normally closed switch valve, 2, low pressure accumulator, 3, safety valve, 4, motor, 5, hydraulic pressure constant displacement pump, 6, hydraulic pressure
Servo amplifier, 7, check valve, 8, hydraulic efficiency servo-valve, 9, hydraulic lock, 10, pressure sensor, 11, hydraulic cylinder, 12, displacement sensing
Device, 13, guide rail, 14, sliding block, 15, hydraulic cylinder piston rod, 16, ball pivot.
Embodiment
In the active control hydraulic servo buffer shown in Fig. 1 and Fig. 2, low pressure accumulator 2 and the phase of normally closed switch valve 1
Even, the low pressure accumulator is connected with the hydraulic pressure constant displacement pump 5 equipped with motor 4, the hydraulic pressure constant displacement pump and the import phase of check valve 7
Even, the outlet of the check valve 7 is connected with the oil inlet of hydraulic efficiency servo-valve 8, and hydraulic efficiency servo-valve oil return opening exports phase with low pressure accumulator
Even.The outlet of check valve 7 is connected with the entrance of safety valve 3, and safety valve 3 is direct acting type overflow valve, the outlet of safety valve 3 and low pressure accumulation of energy
Device outlet is connected.The hydraulic efficiency servo-valve is three-position four-way hydraulic servo valve, which is provided with servo amplifier 6, electromagnet sv1,
Two interfaces of the hydraulic efficiency servo-valve oil-out respectively with two oil inlet phases of the hydraulic lock 9 being made up of two hydraulic control one-way valves
Even, the oil-out of hydraulic lock 9 is connected with the rodless cavity of hydraulic cylinder 11 and rod chamber respectively, and wherein hydraulic lock 9 is connected with rodless cavity
Pipeline is provided with pressure sensor 10.Displacement transducer 12 is provided with piston rod in hydraulic cylinder, hydraulic cylinder piston rod 15
Outer end is be hinged by ball pivot 16 and sliding block 14, and sliding block is located on the corresponding sliding pair of guide rail 13.
The present invention the course of work approximately as:When device is impacted by external applied load, pushed away by mechanical connection part
Hydrodynamic pressure cylinder piston rod 16 and hydraulic piston are acted, and the hydraulic oil in closed containing cavity is equivalent to a kind of spring of big rigidity
(being referred to as hydraulic spring grease cup), after being acted on by hydraulic piston, hydraulic spring grease cup compresses, the hydraulic fluid pressure liter of rodless cavity in hydraulic cylinder
Height, after pressure oil pressure value is increased to certain limit, pressure sensor 10 passes measured signal, three-position four-way hydraulic
The valve element of servo valve 8 is acted so that 8 left access systems of servo valve, by controlling 8 left opening degrees of servo valve, in 0.2s
Cause system is hit to drop in specified range in time, and hydraulic oil discharge is partly into low pressure accumulator 2
Stored.
After load impacting terminates, mechanical connection part needs to reset to the position specified, now in pressure sensor
In the case that 10 monitor transmission signal jointly with displacement transducer 12, the valve element of three-position four-way hydraulic servo valve 8 is acted so that
Valve element is located at right working position, changes the flow direction of hydraulic pressure oil medium, and hydraulic oil enters the rodless cavity of hydraulic cylinder 11, and then
The action of liquid presses piston pole 16 is promoted, in the presence of displacement transducer 12 and pressure sensor 10, realizes closing for position and power
Ring controls, and then fast accurate completes action, and hydraulic efficiency servo-valve 8 receives the signal of sensor outflow after the completion of action,
So that valve element is located at middle position, the technical requirements of pressurize are carried out.The pressure of system can control certain model in set-point after pressurize
Enclose, the power to load shedding object is then converted into by hydraulic cylinder, realize some specific functions of load shedding object, such as system
Acceleration etc., and then realize some functions of load shedding object.