Improved control valve gear shifting mechanism and control method
Technical Field
The invention belongs to the technical field of air valve control, and relates to an air valve gear shifting mechanism for controlling starting, stopping and lifting in a dumper, in particular to a gear shifting mechanism capable of realizing more multifunctional control and a control method.
Background
At present, the control of a carriage of a dump truck generally comprises control operations of intermediate stop, lifting and slow descending. With the development of society, the working efficiency of the dump truck is also continuously improved. The slow-down function is a function provided for avoiding a certain influence on a vehicle chassis, and meanwhile, the safety factor of a driver is improved by the function of firstly slow-down and then fast-down, but in specific work, when the chassis is not influenced by confirmation, the working efficiency is improved as much as possible. For example, when the carriage stops and needs to descend, the carriage needs to descend slowly, and when the carriage stably descends, the carriage can descend quickly without influence on the vehicle. The prior art does not relate to the fact that only one descending state exists, either too fast or too slow. If it is desired to achieve a slow first then a fast second, it is desirable to have at least two states of descent for the control valve. The improved slow-falling control air valve with the patent number 201610340048.6 is used for realizing the slow-falling function, and only one cam is arranged, and two sets of pneumatic valve core components are symmetrically arranged along the radial direction of a cam shaft, so that the cam structure can only realize the switching of three states, namely two valve cores are closed at the same time at a middle stop position, and one valve core is opened or two valve cores are opened at the same time during the switching, and no other state exists. Such a structure implements relatively few functions and cannot meet the current customer needs. In addition, the control sequence of the prior slow-falling control air valve is that the valve core is opened from one of the valve cores after being completely closed to carry out lifting operation, two air valves are opened simultaneously when the valve core needs to fall, and the two air valves are closed simultaneously when the valve core stops, so that instant negative pressure of an air path can be caused, the pressure of a main air path is increased, and the service life of an air path system is influenced.
Disclosure of Invention
The invention aims to solve the technical problem of function deficiency caused by less relative states of a control valve, and designs an improved control valve gear shifting mechanism and a control method.
The invention adopts the technical scheme that the improved control air valve gear shifting mechanism comprises a valve body, two sets of pneumatic valve core assemblies arranged in the valve body, an upper cover arranged above the valve body, and a cam mechanism which is provided with a gear shifting handle and used for driving the pneumatic valve core assemblies and is arranged in the upper cover, and the key points are as follows: the cam mechanism comprises a cam shaft fixedly connected with the gear shifting handle, and a first cam and a second cam which are fixed on the cam shaft in parallel, wherein the first cam and the first pneumatic valve core assembly form a first pneumatic control structure, the second cam and the second pneumatic valve core assembly form a second pneumatic control structure, and the first pneumatic valve core assembly and the second pneumatic valve core assembly are symmetrically arranged along the axial direction of the cam shaft.
The pneumatic valve core assembly comprises a steel ball, a gas valve core, a return spring, a sealing plug and a sealing spring which are sequentially arranged from top to bottom, and the steel ball and the first cam or the second cam form top tight fit.
The control air valve gear shifting mechanism is applied to the control of the lifting structure of the dump truck.
The invention also relates to a control method of the control air valve gear shifting mechanism, which is characterized in that the two air valve cores are controlled to be in an open state at the same time, then one of the air valve cores is controlled to be in a closed state, and the other air valve core is controlled to be in an open state, so that the state switching of the two air valve cores is realized.
The core technology of the invention is that on the basis of the original structure, a cam is added, and the layout structure of two sets of pneumatic valve core assemblies is changed, so that the two cams respectively control one pneumatic valve core assembly. Therefore, not only can one valve core be opened and the two valve cores be opened simultaneously, but also one valve core can be closed on the basis that the two valve cores are opened simultaneously, a control state is added, and more functions can be realized.
The control valve gear shifting mechanism has the beneficial effects that when the control valve gear shifting mechanism is applied to a specific lifting structure of a dumper, the function of quick descending is added, and more choices are provided for operators. When the speed is required to be lowered slowly, the gear is changed into a slow-lowering gear, and when the speed is required to be lowered quickly, the gear can be changed into a fast-lowering gear. The invention has the advantages that the slow-falling function is to open the two air paths simultaneously, when the fast-falling function needs to be switched, the switching can be realized only by closing one of the two air paths, and when the switching is performed, because one of the two air paths which are all opened before is closed, the air path pipeline is not subjected to larger air impact, the damage of an air path driving mechanism caused by the fact that the air paths are completely closed when the two air paths are closed simultaneously is avoided, and the service life of the pneumatic system is prolonged.
The present invention will be described in detail with reference to the accompanying drawings.
Drawings
Fig. 1 is a schematic cross-sectional view of the present invention.
Fig. 2 is a schematic sectional view taken along line a-a in fig. 1.
Fig. 3 is a schematic sectional view taken along line B-B in fig. 1.
Fig. 4 is a perspective view of a cam structure.
Fig. 5 is a three-dimensional structure embodiment of the valve shifting mechanism of the invention.
In the drawing, 1 is a gear shift handle, 2 is an upper cover, 31 is a first cam, 32 is a second cam, 4 is a cam shaft, 5 is a steel ball, 6 is an air valve core, 7 is a valve body, 8 is a return spring, 9 is a sealing plug, and 10 is a sealing spring.
Detailed Description
Referring to fig. 1 to 4, an improved shift mechanism of a control valve comprises a valve body 7, two sets of pneumatic valve core assemblies arranged in the valve body 7, an upper cover 2 arranged above the valve body 7, and a cam mechanism with a shift handle 1 arranged in the upper cover 2 and used for driving the pneumatic valve core assemblies, wherein the key points are as follows: the cam mechanism comprises a cam shaft 4 fixedly connected with the gear shifting handle 1, and a first cam 31 and a second cam 32 which are fixed on the cam shaft 4 in parallel, wherein the first cam 31 and a first pneumatic valve core assembly form a first pneumatic control structure, the second cam 32 and a second pneumatic valve core assembly form a second pneumatic control structure, and the first pneumatic valve core assembly and the second pneumatic valve core assembly are symmetrically arranged along the axial direction of the cam shaft 4.
The pneumatic valve core assembly comprises a steel ball 5, a gas valve core 6, a return spring 8, a sealing plug 9 and a sealing spring 10 which are sequentially arranged from top to bottom, wherein the steel ball 5 is tightly matched with the first cam 31 or the second cam 32 in a propping manner.
The control air valve gear shifting mechanism is applied to the control of the lifting structure of the dump truck.
The invention also relates to a control method of the control valve gear shifting mechanism, which is characterized in that: firstly, the two air valve cores 6 are controlled to be in an open state at the same time, then one air valve core 6 is controlled to be in a closed state, and the other air valve core 6 is controlled to be in an open state, so that the states of the two air valve cores 6 are switched.
In the specific implementation of the invention, referring to fig. 5, at the time of fig. 5, the shift handle 1 is at the middle stop position, both the two gas valve cores 6 are in the closed state, when the shift handle 1 is pushed forward to the lifting gear, which is not shown in the figure, at this time, because the first cam 31 and the second cam 32 rotate simultaneously, one of the gas valve cores is in the closed state, the other gas valve core 6 presses the steel ball 5 downwards, the sealing plug 9 is opened through the transmission of the return spring 8 and the sealing spring 10, the gas valve core 6 is opened to ventilate, the function realized at this position is lifting, the working state of the gas valve is switched from the fully closed state to the state that one gas valve core 6 is opened and one gas valve core 6 is closed, and the lifting gear of the shift handle 1 is switched to the middle stop position after the shift handle is lifted to the.
When the gear needs to descend, the gear shifting handle 1 is moved backwards to one gear, the steel balls 5 are pressed by the two air valve cores 6 at the same time, the principle is the same as that of the prior art, too much description is not needed, and the two air valve cores 6 are switched to be in an open state from a closed state at the moment, so that the slow descending function is realized.
The initial slow descending is mainly used for ensuring that a vehicle chassis is not damaged, but the vehicle chassis is stable after being pneumatically driven, at the moment, in order to improve the working efficiency, the fast descending can be carried out to accelerate the working beat, the gear shifting handle 1 is moved backwards to a fast descending gear, at the moment, one of the two cams can release the extrusion of the steel ball 5, and finally the air valve core 6 is closed to ventilate. The state is switched from the state that the two gas valve cores 6 are both opened to the state that the two gas valve cores are opened and closed, so that the gas circuit is switched. When the gear shifting handle 1 rapidly descends to a certain position, the gear shifting handle 1 can be pushed to move forwards to a slow descending gear, the gear shifting handle 1 is slowly descended again until the gear shifting handle 1 is switched to a middle gear stopping position after descending to the proper position, the two air valve cores 6 are completely closed, and the whole control operation process is completed.