A kind of stroking mechanism of plunger pump
Technical field
The invention belongs to field of mechanical technique, relate to the stroking mechanism of a kind of plunger pump, particularly plunger pump.
Background technique
Plunger pump is one of of paramount importance dynamical element in the Hydraulic Field, variable displacement pump in the plunger pump is widely used in extruding, forging, steel rolling and injection moulding etc. mechanically, it is to promote the swash plate swing by variable piston that the output flow of variable displacement pump changes, and realizes the requirement of different flow.The structural type of stroking mechanism directly has influence on the response characteristic of variable piston POF.
The variable actuator of hydraulic planger pump mainly contains three kinds of modes: mechanical mechanism, hydraulic servomechanism and oil hydraulic cylinder etc.The mechanical type stroking mechanism is the variable mode that directly changes swashplate angle with the mechanical connection of rigidity; Hydraulic servo formula stroking mechanism is realized variable by the swash plate body of hydraulic amplifier action oil hydraulic pump; The hydraulic cylinder type stroking mechanism is that the swash plate body with oil hydraulic cylinder action oil hydraulic pump carries out variable.
Traditional stroking mechanism all is the structural type that adopts the single-column plug cylinder, the maximum pendulum angle scope that is swash plate is only determined by the stroke of variable piston, by the stretching out and withdraw of plunger rod, promote the increase of swash plate pivot angle and reduce, thereby control the change of plunger pump output flow.The stroking mechanism of single plunger cylinder structure form is in the variable process, can not realize the change level adjusting of variable speed, be that the propelling of variable piston and the speed of withdrawal are on the same speed step all the time, this specific character makes that the response time of stroking mechanism is long, has reduced the response performance of the output flow of plunger pump.
Its publication number of Chinese patent CN201461287U provides " a kind of plunger variable oil hydraulic pump ", and it comprises housing, bonnet, transmission shaft and axle plug etc., because the quantity of axle plug is one, and axle plug moving process medium velocity unanimity.Make that its response time is long, same, it also exists the problem of response performance difference of the output flow of plunger pump.
Summary of the invention
The objective of the invention is stroking mechanism at the more intense a kind of plunger pump of the response performance of the existing output flow that makes plunger pump.
Purpose of the present invention can realize by following technical proposal: a kind of stroking mechanism of plunger pump, comprise swash plate, piston shoes, plunger and cylinder barrel etc., the both sides of swash plate all have protrusion and contacting part that be circular arc, the quantity of piston shoes is the two ends that two and these two piston shoes are movably connected on swash plate respectively, one end and the plunger pump of above-mentioned cylinder barrel are connected, one end of plunger is positioned at cylinder barrel, the other end of plunger links to each other with above-mentioned piston shoes, it is characterized in that having the transformational structure that in the plunger telescopic process, can move it rapid change on the described plunger.
In the stroking mechanism of this plunger pump, the fluid drive plunger in the cylinder barrel moves with respect to cylinder barrel.Making plunger be transferred at a slow speed by fast moving under the transformational structure effect moves.Shortened the response time of stroking mechanism.
In the said process, when wherein a plunger was withdrawn, an other plunger stretched out.Because the contacting part of swash plate contacts with plunger pump, therefore, the plunger of withdrawal drives the swash plate swing by piston shoes, reaches the purpose of the variable mode that changes swashplate angle after the swash plate swing.
In the stroking mechanism of above-mentioned plunger pump, described transformational structure is tubular plunger one and is shaft-like plunger two, plunger one is formed above-mentioned plunger with plunger two, and an end of plunger two links to each other with above-mentioned piston shoes, the other end of plunger two is positioned at plunger one, and plunger one is positioned at above-mentioned cylinder barrel.
During cavity in fluid enters plunger one, move plunger two fast moving in this process with respect to plunger one at the pressure effect lower plunger two of this fluid.When plunger two moved to limit position, fluid entered the rod chamber of cylinder barrel, and plunger one moves at a slow speed.
In the stroking mechanism of above-mentioned plunger pump, be provided with seal ring one between the outside, place, described plunger one end and the cylinder barrel inboard.
By realizing sealing between a pair of plunger one of seal ring and the cylinder barrel, simultaneously, plunger one can move with respect to cylinder barrel smoothly.
In the stroking mechanism of above-mentioned plunger pump, the end of described plunger one has the oil inlet hole that its inner chamber is communicated with cylinder barrel, all has the spill port that communicates with cylinder barrel on described plunger one and the plunger two.
Under the effect of oil inlet hole and spill port, make fluid in the plunger one and the fluid between plunger one and the plunger two to circulate.
In the stroking mechanism of above-mentioned plunger pump, the end opposite port inboard of described plunger one oil inlet hole has ringwise the retaining that protrudes along one, the other end of described plunger two outside has the retaining that protrudes ringwise along two, described retaining along one and plunger two between be provided with seal ring two, described retaining along two and plunger one between be provided with seal ring three.
Plunger one is with after plunger two is connected, retaining along one with the effect lower plunger one of retaining along two formation one cavity between inboard and plunger two outsides.Simultaneously, seal by seal ring two and three pairs of these cavitys of seal ring.That is to say that fluid just can promote in the plunger two withdrawal plungers one after entering the cylinder cavity.
In the stroking mechanism of above-mentioned plunger pump, described retaining is along having recessed sealing seat one on one, and above-mentioned seal ring two is positioned at sealing seat one place.
The a pair of seal ring of sealing seat two location avoid seal ring two to come off or loosening.
In the stroking mechanism of above-mentioned plunger pump, described retaining is along having recessed sealing seat two on two, and above-mentioned seal ring three is positioned at sealing seat two places.
Two groups of seal rings of sealing seat three location avoids seal ring three to come off or loosening.
In the stroking mechanism of above-mentioned plunger pump, axially have spill port one along it in described plunger one sidewall, an end of spill port one communicates with plunger one inner chamber, and the other end of spill port one communicates with above-mentioned cylinder barrel.
By spill port one plunger one inner chamber is connected with cylinder barrel.
In the stroking mechanism of above-mentioned plunger pump, retaining has spill port two along two inboard on the described plunger two, and an end of spill port two is positioned at retaining along two sidepieces, and the other end of spill port two is positioned at retaining along inboard.
Effect lower plunger one and the fluid between the plunger two at spill port two can enter in the spill port one more smoothly.Certainly, the fluid in the spill port one enters in the cylinder barrel at last.
Compared with prior art, the stroking mechanism of this plunger pump is because plunger is made up of plunger one and plunger two, and plunger two fast moving, plunger one move at a slow speed.That is to say that the response time of this stroking mechanism is short, increased the response performance of the output flow of plunger pump, have the higher utility of ratio.
Description of drawings
Fig. 1 is the perspective view of the stroking mechanism of this plunger pump.
Fig. 2 is the sectional structure schematic representation of plunger one and plunger two in the stroking mechanism of this plunger pump.
The structural representation of plunger one in the stroking mechanism of this plunger pump of Fig. 3.
Fig. 4 is the structural representation of plunger two in the stroking mechanism of this plunger pump.
Among the figure, 1, swash plate; 1a, contacting part; 2, piston shoes; 3, plunger one; 3a, retaining are along one; 3b, sealing seat one; 3c, oil inlet hole; 3d, spill port one; 4, plunger two; 4a, retaining are along two; 4b, sealing seat two; 4c, spill port two; 5, cylinder barrel; 6, seal ring one; 7, seal ring two; 8, seal ring three.
Embodiment
As depicted in figs. 1 and 2, the stroking mechanism of this plunger pump comprises swash plate 1, piston shoes 2, plunger and cylinder barrel 5 etc.
Has fluid in the cylinder barrel 5.The both sides of swash plate 1 all have contacting part 1a protrusion and that be circular arc, and this contacting part 1a is resisted against on the plunger pump.The quantity of piston shoes 2 is two, and these two piston shoes 2 are movably connected in the two ends of swash plate 1 respectively, in the present embodiment, have spherical notch on the swash plate 1, have bulb on the piston shoes 2, the contact of both spheres makes that piston shoes 2 can be with respect to swash plate 1 swing and can be by coming off on the swash plate 1.
As shown in Figure 3 and Figure 4, plunger is made up of plunger 1 and plunger 24, and plunger 1 is cylindric, and plunger 24 is column.One end of plunger 24 links to each other with above-mentioned piston shoes 2, and the other end of plunger 24 is positioned at plunger 1, and plunger 1 is positioned at above-mentioned cylinder barrel 5, in the present embodiment, is provided with seal ring 1 between the outside, place, the end of plunger 1 and cylinder barrel 5 inboards.
The end of plunger 1 has the oil inlet hole 3c that its inner chamber is communicated with cylinder barrel 5, all has the spill port that communicates with cylinder barrel 5 on described plunger 1 and the plunger 24.Spill port comprises spill port one 3d and spill port two 4c.
Spill port one 3d is arranged in plunger one 3 sidewalls and axially is provided with along plunger 1, and the end of spill port one 3d communicates with plunger one 3 inner chambers, and the other end of spill port one 3d communicates with above-mentioned cylinder barrel 5.Spill port two 4c are positioned at the inboard of retaining along two 4a, and the end of spill port two 4c is positioned at retaining along two 4a sidepieces, and the other end of spill port two 4c is positioned at retaining along two 4a inboards.
The end opposite port inboard of plunger one 3 oil inlet hole 3c has ringwise the retaining that protrudes along a 3a, the other end of described plunger 24 outside has the retaining that protrudes ringwise along two 4a, described retaining is provided with seal ring 27 between a 3a and plunger 24, described retaining is provided with seal ring 38 between two 4a and plunger 1.In the present embodiment, retaining is along having recessed sealing seat one 3b on the 3a, and above-mentioned seal ring 27 is positioned at sealing seat one 3b place; Retaining is along having recessed sealing seat two 4b on two 4a, above-mentioned seal ring 38 is positioned at sealing seat two 4b places.
Under the plunger pump original state, swash plate 1 is in the maximum pendulum angle position, and last end plug 1 and plunger 24 are in the state that stretches out fully, and following end plug 1 and plunger 24 are in complete retracted mode.After plunger pump starts, when the output flow of the required pump of system reduces, plunger action on this moment, following end plug is along with motion.Lower end plunger one place, control oil at first enters spill port one 3d, and control oil enters in the inner chamber of plunger 1 more then.This moment, oil pressure acted on the plunger 24, make plunger 24 with 1 swing of fast speeds pulling swash plate, after plunger 24 is retracted to its limit position, control oil enters the inner chamber of cylinder barrel 5, the oil pressure of control oil acts on the plunger 1, make plunger 24 and plunger 1 cylinder barrel 5 of withdrawing simultaneously, this moment, plunger 1 approached the target pivot angle with slower speed pulling swash plate 1.When swash plate 1 need be swung in the other direction, this moment is the end plug withdrawal down, and last end plug is stretched out, and working procedure is similar to the above.
Certainly, have an oilhole that communicates with plunger one 3 spill ports one 3d on cylinder barrel 5, the control oil sources is connected with this oilhole, and the control oil that is entered by this oilhole just can enter among spill port one 3d of plunger 1.And, when plunger 1 also can keep this oilhole to be connected with spill port one in respect to cylinder barrel 5 moving process.
The parallel symmetric arrangement of two groups of plungers has guaranteed that swash plate 1 can realize quick propelling, the function of approaching at a slow speed under positive and negative pivot angle state.Advance and approach at a slow speed the combination in two stages fast, not only can improve plunger pump output discharge capacity and reach desired value, and greatly reduce the overshoot of response process, improved the precision of response with fast speeds.