CN108869464B - Hydraulic device, hot chamber die casting machine and use method of hydraulic device - Google Patents
Hydraulic device, hot chamber die casting machine and use method of hydraulic device Download PDFInfo
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- CN108869464B CN108869464B CN201810872659.4A CN201810872659A CN108869464B CN 108869464 B CN108869464 B CN 108869464B CN 201810872659 A CN201810872659 A CN 201810872659A CN 108869464 B CN108869464 B CN 108869464B
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- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000004512 die casting Methods 0.000 title claims abstract description 13
- 239000003921 oil Substances 0.000 claims abstract description 473
- 230000001360 synchronised effect Effects 0.000 claims abstract description 186
- 239000010720 hydraulic oil Substances 0.000 claims abstract description 75
- 230000000875 corresponding effect Effects 0.000 claims description 16
- 230000001502 supplementing effect Effects 0.000 claims description 13
- 230000001276 controlling effect Effects 0.000 claims description 4
- 230000005484 gravity Effects 0.000 claims description 3
- 238000011065 in-situ storage Methods 0.000 claims description 2
- 230000005611 electricity Effects 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 8
- 238000009434 installation Methods 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000001174 ascending effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/08—Servomotor systems incorporating electrically operated control means
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
- B22D17/02—Hot chamber machines, i.e. with heated press chamber in which metal is melted
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
- B22D17/20—Accessories: Details
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Actuator (AREA)
Abstract
The invention is suitable for the technical field of hydraulic devices, and discloses a hydraulic device, a hot chamber die casting machine and a use method of the hydraulic device. The hydraulic device comprises a synchronous large oil cylinder, at least two synchronous small oil cylinders driven by the synchronous large oil cylinder and at least two action oil cylinders which are respectively and synchronously driven by the synchronous small oil cylinders and are used for driving the platform to move, wherein a piston rod of the synchronous large oil cylinder is connected with a piston rod of each synchronous small oil cylinder, a rodless cavity of each synchronous small oil cylinder is correspondingly communicated with a rodless cavity of one action oil cylinder through a serial oil pipe, and a piston rod of each action oil cylinder is connected with the platform. The invention provides a hydraulic device, a hot chamber die casting machine and a use method of the hydraulic device, wherein the hydraulic device has high flow, low requirements on manufacturing process of connection of oil cylinders, low pressure loss, good unbalanced load resistance, strong pollution resistance to hydraulic oil, simple oil way and no need of expert knowledge.
Description
Technical Field
The invention belongs to the technical field of hydraulic devices, and particularly relates to a hydraulic device, a hot chamber die casting machine and a use method of the hydraulic device.
Background
The multi-cylinder synchronization of the hydraulic cylinder mainly comprises synchronization valve synchronization, synchronization cylinder synchronization, synchronization motor synchronization, mechanical synchronization, compound control and proportional servo system synchronization, the traditional hydraulic device is small in flow, the manufacturing process of connection of the cylinders is high in requirement, pressure loss is large, the unbalanced load capacity of the compound control method is poor, repeated adjustment is needed, the pollution resistance to hydraulic oil is poor, an oil way is complex, and expert expertise is needed.
Disclosure of Invention
The invention aims to solve at least one of the technical problems, and provides a hydraulic device, a hot chamber die casting machine and a use method of the hydraulic device, wherein the hydraulic device has high flow, low requirements on manufacturing process of connection of oil cylinders, low pressure loss, good unbalanced load resistance, no need of repeated adjustment, strong pollution resistance to hydraulic oil, simple oil way and no need of expert knowledge.
The technical scheme of the invention is as follows: the hydraulic device comprises a synchronous large oil cylinder, at least two synchronous small oil cylinders driven by the synchronous large oil cylinder and at least two action oil cylinders which are respectively driven by the synchronous small oil cylinders synchronously and used for driving a platform to move, wherein a piston rod of each synchronous large oil cylinder is connected with a piston rod of each synchronous small oil cylinder, a rodless cavity of each synchronous small oil cylinder is correspondingly communicated with a rodless cavity of one action oil cylinder through a serial oil pipe, and a piston rod of each action oil cylinder is connected with the platform.
Specifically, the piston rod of each small synchronous oil cylinder is fixed on the piston rod of the large synchronous oil cylinder through a piston rod fixing piece, and a plurality of small synchronous oil cylinders are arranged along the piston rod fixing piece.
Specifically, the hydraulic device further comprises an oil inlet pipe, an oil outlet pipe, a first oil pipe and a second oil pipe, wherein the first oil pipe is communicated with a rod cavity of the action oil cylinder, and the second oil pipe is communicated with a rodless cavity of the synchronous large oil cylinder; the reversing valve is connected between the oil inlet pipe and the oil outlet pipe, and between the oil outlet pipe and the first oil pipe and the second oil pipe, and is provided with parallel channels for communicating the oil inlet pipe and the first oil pipe and communicating the oil outlet pipe and the second oil pipe and cross channels for communicating the oil inlet pipe and the second oil pipe and communicating the oil outlet pipe and the first oil pipe.
Specifically, the hydraulic device further comprises at least two parallel oil pipes, one end of each parallel oil pipe is communicated with the corresponding serial oil pipe, and the other end of each parallel oil pipe is communicated with the first oil pipe.
Specifically, each parallel oil pipe is provided with a stop valve for controlling the on-off of the parallel oil pipe.
Specifically, the oil inlet pipe is provided with a one-way valve for preventing the backflow of hydraulic oil.
The invention also provides a hot chamber die casting machine, which is provided with the hydraulic device.
The invention also provides a use method of the hydraulic device, which adopts the hydraulic device and comprises the following steps: hydraulic oil enters the rodless cavity of the synchronous large oil cylinder, the piston rod of the synchronous large oil cylinder pushes the piston rod of each synchronous small oil cylinder, hydraulic oil in the rodless cavity of each synchronous small oil cylinder flows to the corresponding rodless cavity of the action oil cylinder and pushes the piston rod of the action oil cylinder to extend outwards, and each action oil cylinder synchronously pushes the platform to ascend.
Specifically, the method comprises the following steps: the hydraulic device system outputs pressure to enable a piston rod of the action oil cylinder not to extend outwards, a reversing valve of a control oil way is firstly electrified, hydraulic oil enters a rodless cavity of a synchronous large oil cylinder from a second oil pipe through an oil inlet pipe, hydraulic oil in the rodless cavity of the action oil cylinder can flow from a first oil pipe to an oil outlet pipe, the hydraulic oil enters the rodless cavity of the synchronous large oil cylinder and pushes the piston rod of the synchronous large oil cylinder to extend outwards and push the piston rod of the synchronous small oil cylinder to retract, gas in the rodless cavity of the synchronous small oil cylinder is discharged through a parallel oil pipe connected with the serial oil pipe, then the reversing valve is deenergized, the second oil pipe is communicated with the oil outlet pipe, the first oil pipe is communicated with the oil inlet pipe, the hydraulic oil enters the rodless cavity of the synchronous small oil cylinder from the parallel oil pipe through the serial oil pipe to conduct oil supplementing action, and the piston rod of the action oil cylinder is completely retracted, and the piston rod of the action oil cylinder is opened to control a stop valve of the dead weight of the parallel oil pipe before all steps are operated;
or, the hydraulic device is firstly used for enabling the piston rods of the synchronous small oil cylinder and the action oil cylinder to extend outwards through adjusting the output pressure of the system, and then stopping pressure output after the piston rods of the action oil cylinder extend outwards, the piston rods of the action oil cylinders retract due to the gravity of a connected platform and discharge gas in the rodless cavity of the action oil cylinder to an oil tank, then the pressure is recovered, a reversing valve is electrified, hydraulic oil enters the rodless cavity of the synchronous large oil cylinder from a second oil pipe through an oil inlet pipe, hydraulic oil can flow to an oil outlet pipe from a first oil pipe, the hydraulic oil enters the rodless cavity of the synchronous large oil cylinder and pushes the piston rods of the synchronous large oil cylinder, the piston rods of the synchronous large oil cylinder extend outwards and push the piston rods of the synchronous small oil cylinder to retract, the gas in the rodless cavity of the synchronous small oil cylinder is discharged through a parallel oil pipe, the reversing valve is in power failure, the first oil pipe is communicated with the oil inlet pipe, the hydraulic oil enters the rodless cavity of the synchronous small oil cylinder through the parallel oil pipe, and the stop valve before all the steps are operated to open.
According to the hydraulic device, the hot chamber die casting machine and the using method of the hydraulic device, the hydraulic device obtains required flow by adding a plurality of synchronous small oil cylinders or adding the diameter of the synchronous small oil cylinders and correspondingly connecting with one action oil cylinder, so that the flow is increased, and the diameters of the synchronous small oil cylinders and the corresponding action oil cylinders are the same, and because of the synchronous volumes, the synchronous precision is high, so that the unbalanced load resistance of the hydraulic device is high, repeated adjustment is not needed, and the pollution resistance to hydraulic oil is high; the synchronous small oil cylinders are connected with the action oil cylinders through oil pipes, the installation positions of the action oil cylinders can be flexibly arranged, the adjustment is simple, the manufacturing process of the connection of the oil cylinders is low in requirement, the pressure loss is low, the price is low, and the oil way is simple without expert expertise.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic system diagram of a hydraulic device according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
It should be noted that the terms "disposed" and "connected" should be construed broadly, and may be, for example, directly disposed, mounted, connected, or indirectly disposed, connected through a central element or central structure.
In addition, the directions or positional relationships indicated by "large", "small", "ascending", "descending", "inner", "outer", etc. in the embodiments of the present invention are based on the directions or positional relationships shown in the drawings, and are merely for convenience of description and simplification of description, and are not indicative or implying that the structures, features, devices or elements to be referred to must have a specific direction, be configured and operated in a specific direction, and thus should not be construed as limiting the present invention. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.
As shown in fig. 1, the hydraulic device provided by the embodiment of the invention comprises a synchronous big oil cylinder 11, at least two synchronous small oil cylinders 12 and at least two action oil cylinders 13, wherein a plurality of synchronous small oil cylinders 12 are driven by the same synchronous big oil cylinder 11, each action oil cylinder 13 is correspondingly connected with one synchronous small oil cylinder 12 through an oil pipe, each action oil cylinder 13 is synchronously driven by the corresponding synchronous small oil cylinder 12, a piston rod 132 of the action oil cylinder 13 is connected with a driving platform 10 and can drive the platform 10 to move (e.g. lift), and further, the diameter of the action oil cylinder 13 can be consistent with the diameter of the corresponding connected synchronous small oil cylinder 12, so that the platform 10 can move stably. The piston rod 112 of the synchronous big oil cylinder 11 is connected to the piston rod 122 of each synchronous small oil cylinder 12, the rodless cavity 121 of each synchronous small oil cylinder 12 is correspondingly communicated with the rodless cavity 131 of one action oil cylinder 13 through the serial oil pipe 5, namely, each synchronous small oil cylinder 12 and each action oil cylinder 13 are connected with the serial oil pipe 5, the piston rod 132 of each action oil cylinder 13 is connected to the platform 10, namely, when the piston rod 112 of the synchronous big oil cylinder 11 stretches out, the piston rod 122 of each synchronous small oil cylinder 12 is pushed to synchronously retract, hydraulic oil in the rodless cavity 121 of each synchronous small oil cylinder 12 flows to the rodless cavity 131 of the corresponding connected action oil cylinder 13, and the piston rod 132 of each action oil cylinder 13 is pushed to stretch out, and the piston rod 132 of each action oil cylinder 13 pushes the platform 10 to move. The hydraulic device obtains the required flow by increasing a plurality of small synchronous cylinders 12 or increasing the diameter of the small synchronous cylinders 12 and correspondingly connecting one action cylinder 13, so that the flow is increased, and the diameters of the small synchronous cylinders 12 and the corresponding action cylinders 13 can be the same, because of volume synchronization, the synchronization precision is high, the platform 10 can be stably lifted, the unbalanced load condition of uneven stress is overcome, repeated adjustment is not needed, and the pollution resistance to hydraulic oil is strong; the synchronous small oil cylinder 12 and the action oil cylinder 13 are connected through oil pipes, the installation positions of the action oil cylinders 13 can be flexibly arranged, the adjustment is simple, the manufacturing process of the connection of the oil cylinders is low in requirement, the pressure loss is low, the price is low, and the oil way is simple without the need of expert expertise.
The diameter (volume) of the large synchronous cylinder 11 is larger than the diameter (volume) of the small synchronous cylinder 12, and the size thereof is only a relative concept. The cylinder is internally provided with a piston, one end of the piston is connected with a piston rod, one side of the cylinder with the piston rod is provided with a rod cavity, and the other side of the cylinder with the piston rod is provided with a rodless cavity.
More specifically, the flow rate may be increased by increasing the number of the small synchronous cylinders 12 or increasing the diameter of the small synchronous cylinders 12. Since the diameters of the small synchronous cylinder 12 and the action cylinder 13 are consistent, by increasing the number or diameter of the small synchronous cylinder 12, the total amount of hydraulic oil in the rodless cavity 121 of the small synchronous cylinder 12 is increased, and when the piston rod 122 of the small synchronous cylinder 12 is fully extended and the hydraulic oil in the rodless cavity 121 of the small synchronous cylinder 12 is fully discharged, the rodless cavity 131 of the action cylinder 13 obtains the same total amount of hydraulic oil (i.e., the total amount of the hydraulic oil after the increase), and the fully extended stroke of the piston rod 132 of the action cylinder 13 is longer, i.e., the total flow of the hydraulic device is increased.
More specifically, the diameters of the plurality of small synchronous cylinders 12 may be the same, so that the diameters of the plurality of small synchronous cylinders 13 are the same, the flow rate of hydraulic oil flowing into the rodless cavity 131 of the small synchronous cylinders 12 is the same, the piston rods 132 of the plurality of small synchronous cylinders 13 may extend synchronously, the platform 10 may rise stably, the unbalanced load condition of uneven stress is overcome, and the plurality of small synchronous cylinders 12 and the small synchronous cylinders 13 are the same diameter, and the manufacture is convenient.
As shown in fig. 1, specifically, the piston rod 122 of each small synchronous cylinder 12 is fixed to the piston rod 112 of the large synchronous cylinder 11 through the piston rod fixing member 9, so that the large synchronous cylinder 11 can drive multiple small synchronous cylinders 12 simultaneously, and the multiple small synchronous cylinders 12 are arranged along the piston rod fixing member 9, that is, the multiple small synchronous cylinders 12 are adjacently spaced or distributed in parallel, so that the piston rods 122 of the multiple small synchronous cylinders 12 can extend synchronously, the flow rate of hydraulic oil discharged from the rodless cavity 131 of the slave cylinder 13 when the piston rods 132 of the multiple action cylinders 13 retract is limited, and the flow rate of hydraulic oil discharged from the rodless cavity 121 of the small synchronous cylinders 12 when the piston rods 122 of the small synchronous cylinders 12 retract is consistent, so that the piston rods 132 of the multiple action cylinders 13 descend synchronously (that is, retract). In this embodiment, the end of the piston rod 112 of the large synchronous cylinder 11 is fixedly connected to the center of one surface of the piston rod fixing member 9, the end of the piston rod 122 of each small synchronous cylinder 12 is fixedly connected to the other surface of the piston rod fixing member 9, and the piston rods 122 of the small synchronous cylinders 12 can be symmetrically arranged with respect to the center of the piston rod fixing member 9. The piston rod holder 9 may be plate-shaped or rod-shaped, tubular or the like.
As shown in fig. 1, specifically, the hydraulic device further includes an oil inlet pipe 1, an oil outlet pipe 2, a first oil pipe 3 and a second oil pipe 4, wherein the first oil pipe 3 is communicated with a rod cavity 133 of the action cylinder 13, and the second oil pipe 4 is communicated with a rodless cavity 111 of the synchronous big cylinder 11; the reversing valve 7 is connected between the oil inlet pipe 1 and the oil outlet pipe 2 and the first oil pipe 3 and between the oil outlet pipe 2 and the second oil pipe 4, and the reversing valve 7 is provided with parallel channels which can be used for communicating the oil inlet pipe 1 with the first oil pipe 3 and the oil outlet pipe 2 with the second oil pipe 4; the reversing valve 7 is also provided with a cross passage which can communicate the oil inlet pipe 1 with the second oil pipe 4 and the oil outlet pipe 2 with the first oil pipe 3. When the reversing valve 7 is powered off, the valve core is in the original position, namely the oil inlet pipe 1, the oil outlet pipe 2, the first oil pipe 3 and the second oil pipe 4 are communicated with parallel channels of the reversing valve 7, a hydraulic device is started, hydraulic oil can enter the first oil pipe 3 from the oil inlet pipe 1 through the parallel channels of the reversing valve 7, and hydraulic oil can enter the oil outlet pipe 2 from the second oil pipe 4 through the parallel channels of the reversing valve 7; when the reversing valve 7 is powered on, the valve core is displaced, namely the oil inlet pipe 1, the oil outlet pipe 2, the first oil pipe 3 and the second oil pipe 4 are communicated with the cross passage of the reversing valve 7, the hydraulic device is started, hydraulic oil can enter the second oil pipe 4 from the oil inlet pipe 1 through the cross passage of the reversing valve 7, and hydraulic oil can enter the oil outlet pipe 2 from the first oil pipe 3 through the cross passage of the reversing valve 7.
As shown in fig. 1, more specifically, the reversing valve 7 may be a two-position four-way electromagnetic reversing valve including two sets of passages: parallel channel and cross channel, every group all have four valve ports, and are the A mouth, the B mouth, the P mouth, the T mouth, the one end of advance oil pipe 1 is connected in the P mouth, the one end of go out oil pipe 2 is connected in the T mouth, the one end of first oil pipe 3 is connected in the A mouth, the one end of second oil pipe 4 is connected in the B mouth. When the two-position four-way electromagnetic reversing valve is powered off, the valve core is in situ, and the hydraulic device is positioned in the parallel channel: the port A is communicated with the port P, the port B is communicated with the port T, and hydraulic oil enters the first oil pipe 3 through the oil inlet pipe 1; when the two-position four-way electromagnetic reversing valve is electrified, the valve core is displaced, and the hydraulic device is positioned in the cross channel: the port A is communicated with the port T, the port B is communicated with the port P, and hydraulic oil enters the second oil pipe 4 through the oil inlet pipe 1.
As shown in fig. 1, specifically, the hydraulic device further includes at least two parallel oil pipes 6, one end of each parallel oil pipe 6 is connected to the corresponding serial oil pipe 5, and the other end is connected to the first oil pipe 3, when the parallel oil pipe 6 is in a passage, hydraulic oil discharged from the oil pump does not flow to the rod cavity 133 of the actuating cylinder 13 any more, but passes through the first oil pipe 3 and then enters the rodless cavity 121 of the corresponding small synchronous oil cylinder 12 via each parallel oil pipe 6, so that the air exhausting and oil supplementing actions can be performed.
As shown in fig. 1, specifically, each parallel oil pipe 6 is provided with a stop valve 8, and the stop valve 8 is used for controlling the on-off of the parallel oil pipe 6. When the hydraulic device is operated for the first time, the hydraulic oil is not present in the rodless chambers 121 and 131 of the small synchronous cylinder 12 and the small synchronous cylinder 13, and the shut-off valve 8 is opened to form a passage for the parallel oil pipe 6, so that the hydraulic oil is discharged and filled with the gas in the rodless chambers 121 and 131 of the small synchronous cylinder 12 and 13. When the stop valve 8 is closed, the parallel oil pipe 6 is disconnected, and at the moment, hydraulic oil can pass through the rod cavity 133 of the action oil cylinder 13, and the hydraulic device can perform the action of moving the platform 10; when the stop valve 8 is disconnected, the parallel oil pipe 6 is a passage, and at the moment, hydraulic oil passes through the parallel oil pipe 6, and the hydraulic device can perform exhausting and oil supplementing actions.
As shown in fig. 1, in particular, the oil feed pipe 1 is provided with a check valve 14 for preventing the backflow of hydraulic oil, which can prevent the sudden increase of the system pressure of the hydraulic device from damaging the oil pump, i.e., to function as a check.
The invention also provides a hot chamber die casting machine, which is provided with the hydraulic device. The hydraulic device plays a role in executing lifting action in the hot chamber die casting machine, a column frame part of the hot chamber die casting machine is arranged on a platform 10 of the hydraulic device, and the lifting of the platform 10, namely the lifting of the column frame part, is regulated according to different positions of pouring gates of different dies; the hydraulic device is provided with a plurality of small synchronous cylinders 12, each small synchronous cylinder 12 is correspondingly connected with an action cylinder 13 with the same volume, and the platform 10 can lift through the action cylinder 13, so that the precision of synchronization is high, the unbalanced load resistance is good, the column frame part can lift integrally and stably, the situation that the gate position is deviated and material leakage and material flying occur due to large unbalanced load condition during use is prevented, the unbalanced load condition is well solved, and the practical purpose is achieved.
The invention also provides a use method of the hydraulic device, which adopts the hydraulic device and comprises the following steps: hydraulic oil enters the rodless cavity 111 of the synchronous big oil cylinder 11, the piston rod 112 of the synchronous big oil cylinder 11 pushes the piston rod 122 of each synchronous small oil cylinder 12, hydraulic oil in the rodless cavity 121 of each synchronous small oil cylinder 12 flows to the rodless cavity 131 of the corresponding action oil cylinder 13, and pushes the piston rod 132 of the action oil cylinder 13 to extend outwards, and each action oil cylinder 13 synchronously pushes the platform 10 to ascend. The diameters of the synchronous small oil cylinder 12 and the corresponding action oil cylinder 13 of the hydraulic device can be the same, and the synchronous precision is high because of the volume synchronization, so that the unbalanced load resistance of the platform 10 is high, and repeated adjustment is not needed; the synchronous small oil cylinder 12 and the action oil cylinder 13 are connected through oil pipes, the installation positions of the action oil cylinders 13 can be flexibly arranged, the manufacturing process of the connection of the oil cylinders is low in requirement, the pressure loss is low, the price is low, and the oil way is simple without expert expertise.
As shown in fig. 1, the use method specifically further includes a method of exhausting and supplementing oil, and the method includes the following steps: the hydraulic device system outputs pressure, the piston rod 132 of the action cylinder 13 can not extend outwards, the reversing valve 7 of the control oil way is firstly electrified, the rodless cavity 111 of the synchronous big cylinder 11 is connected with the second oil pipe 4, hydraulic oil enters the rodless cavity 111 of the synchronous big cylinder 11 through the second oil pipe 4, the rodless cavity 131 of the action cylinder 13 is connected with the first oil pipe 3, hydraulic oil in the rodless cavity 131 of the action cylinder 13 can flow from the first oil pipe 3 to the oil outlet pipe 2, the hydraulic oil enters the rodless cavity 111 of the synchronous big cylinder 11 and pushes the piston rod 112 of the synchronous big cylinder 11, the piston rod 112 of the synchronous big cylinder 11 extends outwards and pushes the piston rod 122 of the synchronous small cylinder 12 to retract, gas in the rodless cavity 121 of the synchronous small cylinder 12 is discharged through the parallel oil pipe 6, then the reversing valve 7 is deenergized, the second oil pipe 4 is communicated with the oil outlet pipe 2, the hydraulic oil enters the rodless cavity 121 of the synchronous small cylinder 12 from the parallel oil pipe 6 to conduct oil supplementing action, the piston rod 132 of the action cylinder 13 is completely retracted due to self weight, and all the stop valves 8 before the control step 8 are opened are operated. Repeating the power-off action of the reversing valve 7 for a plurality of times, enabling the piston rod 122 of the small synchronous oil cylinder 12 to extend and retract continuously to exhaust, enabling the piston rod 132 of the small synchronous oil cylinder 13 to not act due to the fact that the pressure is too low, exhausting for a plurality of times until the piston rod 122 of the small synchronous oil cylinder 12 is fully extended, enabling the rodless cavity 121 of the small synchronous oil cylinder 12 to be full of hydraulic oil, enabling the piston rod 132 of the small synchronous oil cylinder 13 to fully retract, manually closing all the stop valves 8, driving the platform 10 to do lifting action, observing the synchronicity of the extension and retraction of the piston rod 132 of the small synchronous oil cylinder 13, manually opening all the stop valves 8 again if the piston rod 132 of the small synchronous oil cylinder 13 is out of synchronization, repeating the steps of exhausting and supplementing oil until the air in the rodless cavity 121 of the small synchronous oil cylinder 12 and the rodless cavity 131 of the small synchronous oil cylinder 13 is exhausted, and closing the stop valves 8 after exhausting, and enabling the piston rod 122 of the small synchronous oil cylinder 12 to fully extend and the piston rod 132 of the small synchronous oil cylinder 13 to fully retract.
Or, as an alternative, when the platform 10 is in a test state and the platform 10 has a large dead weight, the hydraulic device is firstly used for outputting pressure through the regulating system, so that the piston rods 132 of the synchronous small oil cylinder 12 and the action oil cylinder 13 extend outwards, the pressure output is stopped after the hydraulic device extends completely, the piston rods 132 of the action oil cylinder 13 retract due to the gravity of the connected platform 10, the gas in the rodless cavity 131 of the action oil cylinder 13 is discharged to the oil tank 16, then the pressure is recovered, the reversing valve 7 is electrified, hydraulic oil enters the rodless cavity 111 of the synchronous large oil cylinder 11 from the second oil pipe 4 through the oil inlet pipe 1, hydraulic oil can flow from the first oil pipe 3 to the oil outlet pipe 2, the hydraulic oil enters the rodless cavity 111 of the synchronous large oil cylinder 11 and pushes the piston rod 112 of the synchronous large oil cylinder 11, the piston rod 112 of the synchronous large oil cylinder 11 extends outwards, the piston rod 122 of the synchronous small oil cylinder 12 is pushed to retract, the gas in the rodless cavity 121 of the synchronous oil cylinder 12 is discharged to the oil tank through the parallel oil pipe 6, the reversing valve 7 is electrified, the second oil pipe 4 is communicated with the oil outlet pipe 2, the first oil pipe 3 is communicated with the oil inlet pipe 6, and all the parallel oil pipes 6 are connected in parallel oil pipe 6 are connected in series through the parallel oil pipe 6, and all the preceding steps of the control of the on-off valve 8 are opened, and the step of stopping is finished. All the steps after the output pressure of the system is regulated are repeated for 3 times, all the air in the rodless cavity 121 of the synchronous small oil cylinder 12 and the rodless cavity 131 of the action oil cylinder 13 can be completely discharged, and when the piston rod 122 of the synchronous small oil cylinder 12 is completely extended and the piston rod 132 of the action oil cylinder 13 is completely retracted, all the stop valves 8 can be closed.
More specifically, when the hydraulic device drives the platform 10, the piston rod 132 of the actuating cylinder 13 extends and retracts to generate an asynchronous condition, and the correction can be performed by adopting the two exhaust and oil supplementing methods, which are simple and effective.
According to the hydraulic device, the hot chamber die casting machine and the using method of the hydraulic device, provided by the embodiment of the invention, the hydraulic device obtains required flow through adding a plurality of small synchronous cylinders 12 or adding the diameter of the small synchronous cylinders 12 and correspondingly connecting one action cylinder 13, so that the flow is increased, and the diameters of the small synchronous cylinders 12 and the corresponding action cylinders 13 are the same, because of volume synchronization, the synchronization precision is high, the unbalanced load resistance of the hydraulic device is high, repeated adjustment is not needed, and the pollution resistance of hydraulic oil is high; the synchronous small oil cylinder 12 and the action oil cylinder 13 are connected through oil pipes, the installation positions of the action oil cylinders 13 can be flexibly arranged, the adjustment is simple, the manufacturing process requirements of the connection of the oil cylinders are low, the pressure loss is low, the price is low, the oil way is simple, and no expert knowledge is needed.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, or alternatives falling within the spirit and principles of the invention.
Claims (5)
1. The hydraulic device is characterized by comprising a synchronous large oil cylinder, at least two synchronous small oil cylinders driven by the synchronous large oil cylinder and at least two action oil cylinders which are respectively and synchronously driven by the synchronous small oil cylinders and are used for driving a platform to move, wherein a piston rod of each synchronous large oil cylinder is connected with a piston rod of each synchronous small oil cylinder, the piston rod of each synchronous small oil cylinder is fixed on the piston rod of the synchronous large oil cylinder through a piston rod fixing piece, a plurality of synchronous small oil cylinders are arranged along the piston rod fixing piece, a plurality of synchronous small oil cylinders are adjacently and uniformly distributed at intervals or in parallel, and the piston rods of the synchronous small oil cylinders are symmetrically arranged relative to the center of the piston rod fixing piece; the end part of the piston rod of each synchronous big oil cylinder is fixedly connected to the center of one surface of the piston rod fixing piece, and the end part of the piston rod of each synchronous small oil cylinder is fixedly connected to the other surface of the piston rod fixing piece; the rodless cavity of each small synchronous oil cylinder is correspondingly communicated with the rodless cavity of one action oil cylinder through a serial oil pipe, the piston rod of each action oil cylinder is connected with the platform, and the diameters of the small synchronous oil cylinders and the corresponding action oil cylinders are the same;
the hydraulic device also comprises an oil inlet pipe, an oil outlet pipe, a first oil pipe and a second oil pipe, wherein the first oil pipe is communicated with a rod cavity of the action oil cylinder, and the second oil pipe is communicated with a rodless cavity of the synchronous large oil cylinder; the reversing valve is provided with parallel channels, and the parallel channels are used for communicating the oil inlet pipe with the first oil pipe and the oil outlet pipe with the second oil pipe; the reversing valve is also provided with a cross channel, the cross channel is used for communicating the oil inlet pipe with the second oil pipe and the oil outlet pipe with the first oil pipe, when the reversing valve is in power failure, the valve core is in the original position, the oil inlet pipe, the oil outlet pipe, the first oil pipe and the second oil pipe are communicated with parallel channels of the reversing valve, a hydraulic device is started, hydraulic oil enters the first oil pipe from the oil inlet pipe through the parallel channels of the reversing valve, and hydraulic oil enters the oil outlet pipe from the second oil pipe through the parallel channels of the reversing valve; when the reversing valve is powered on, the valve core is displaced, namely an oil inlet pipe, an oil outlet pipe, a first oil pipe and a second oil pipe are communicated with a cross channel of the reversing valve, a hydraulic device is started, hydraulic oil enters the second oil pipe from the oil inlet pipe through the cross channel of the reversing valve, and hydraulic oil enters the oil outlet pipe from the first oil pipe through the cross channel of the reversing valve;
the reversing valve adopts a two-position four-way electromagnetic reversing valve, and the two-position four-way electromagnetic reversing valve comprises two groups of channels: parallel channel and cross channel, every group all has four valve ports, and is the A mouth, the B mouth, the P mouth, the T mouth, the one end of advance oil pipe is connected in the P mouth, the one end of play oil pipe is connected in the T mouth, the one end of first oil pipe is connected in the A mouth, the one end of second oil pipe is connected in the B mouth, when two-position cross electromagnetic directional valve loses the electricity, the case is in situ, hydraulic means is in parallel channel this moment: the port A is communicated with the port P, the port B is communicated with the port T, and hydraulic oil enters the first oil pipe through the oil inlet pipe; when the two-position four-way electromagnetic reversing valve is electrified, the valve core is displaced, and the hydraulic device is positioned in the cross channel: the port A is communicated with the port T, the port B is communicated with the port P, and hydraulic oil enters the second oil pipe through the oil inlet pipe;
the hydraulic device further comprises at least two parallel oil pipes, one end of each parallel oil pipe is communicated with the corresponding serial oil pipe, the other end of each parallel oil pipe is communicated with the first oil pipe, when the parallel oil pipe is in a passage, hydraulic oil discharged from the oil pump does not flow to a rod cavity of the action oil cylinder any more, but enters a rodless cavity of the corresponding synchronous small oil cylinder through each parallel oil pipe after passing through the first oil pipe, and the exhaust and oil supplementing actions are carried out;
each parallel oil pipe is provided with a stop valve, the stop valves are used for controlling the on-off of the parallel oil pipes, when the hydraulic device acts for the first time, the rodless cavity of the synchronous small oil cylinder and the rodless cavity of the action oil cylinder are free of hydraulic oil and have gas, the stop valves are required to be opened to enable the parallel oil pipes to form a passage, and the gas in the rodless cavity of the synchronous small oil cylinder and the rodless cavity of the action oil cylinder is discharged and filled with the hydraulic oil; when the stop valve is closed, the parallel oil pipe is disconnected, and at the moment, hydraulic oil passes through a rod cavity of the action oil cylinder, and the hydraulic device moves the platform; when the stop valve is disconnected, the parallel oil pipe is a passage, and at the moment, hydraulic oil passes through the parallel oil pipe, and the hydraulic device performs exhausting and oil supplementing actions.
2. A hydraulic device according to claim 1, wherein the oil inlet pipe is provided with a check valve for preventing the backflow of the hydraulic oil.
3. A hot-chamber die casting machine, characterized by a hydraulic device as claimed in claim 1 or 2.
4. A method of using a hydraulic device according to claim 1 or 2, comprising the steps of: the hydraulic device system outputs pressure, hydraulic oil enters a rodless cavity of the synchronous large oil cylinder from the second oil pipe through the oil inlet pipe through the reversing valve, a piston rod of the synchronous large oil cylinder pushes a piston rod of each synchronous small oil cylinder, hydraulic oil in the rodless cavity of each synchronous small oil cylinder flows to the corresponding rodless cavity of the action oil cylinder and pushes the piston rod of the action oil cylinder to extend outwards, each action oil cylinder synchronously pushes the platform to ascend, and hydraulic oil in the rodless cavity of the action oil cylinder flows from the first oil pipe to the oil outlet pipe and finally flows back to the oil tank;
the use method also comprises the steps of exhausting and supplementing oil, and comprises the following steps: the hydraulic device system outputs pressure, the pressure makes the piston rod of the action oil cylinder not extend outwards, the reversing valve of the control oil way is powered on, the rodless cavity of the synchronous big oil cylinder is connected with the second oil pipe, hydraulic oil enters the rodless cavity of the synchronous big oil cylinder through the second oil pipe, the rodless cavity of the action oil cylinder is connected with the first oil pipe, hydraulic oil in the rodless cavity of the action oil cylinder flows from the first oil pipe to the oil outlet pipe, hydraulic oil enters the rodless cavity of the synchronous big oil cylinder and pushes the piston rod of the synchronous big oil cylinder, the piston rod of the synchronous big oil cylinder extends outwards and pushes the piston rod of the synchronous small oil cylinder to retract, gas in the rodless cavity of the synchronous small oil cylinder is discharged through the parallel oil pipe, then the reversing valve is powered off, the second oil pipe is communicated with the oil outlet pipe, the first oil pipe is communicated with the oil inlet pipe, hydraulic oil enters the rodless cavity of the synchronous small oil cylinder from the parallel oil pipe through the serial oil pipe for oil supplementing action, the piston rod of the action cylinder is fully retracted by dead weight, the stop valve for controlling the on-off of the parallel oil pipe is opened before the steps are operated, the electric action of the reversing valve is repeated for a plurality of times, the piston rod of the synchronous small oil cylinder is continuously extended and retracted for exhausting, the piston rod of the action cylinder is not actuated due to the excessively low pressure, the piston rod of the synchronous small oil cylinder is exhausted for a plurality of times until the piston rod of the synchronous small oil cylinder is fully extended, the rodless cavity of the synchronous small oil cylinder is filled with hydraulic oil, the piston rod of the action cylinder is fully retracted, all the stop valves are manually closed, the lifting action of a driving platform is carried out, the synchronicity of the extension and retraction of the piston rod of the action cylinder is observed, all the stop valves are manually opened again if the piston rod of the synchronous small oil cylinder is not synchronized, the steps of exhausting and supplementing oil are repeated until the air in the rodless cavity of the synchronous small oil cylinder and the rodless cavity of the action cylinder is exhausted, at the moment, the piston rod of the synchronous small oil cylinder is completely extended, and the piston rod of the action oil cylinder is completely retracted.
5. A method of using a hydraulic device according to claim 4, comprising the steps of: the hydraulic device system outputs pressure to enable a piston rod of the action oil cylinder not to extend outwards, a reversing valve of a control oil way is powered on firstly, hydraulic oil enters a rodless cavity of a synchronous large oil cylinder from a second oil pipe through an oil inlet pipe, hydraulic oil in the rodless cavity of the action oil cylinder can flow from a first oil pipe to an oil outlet pipe, the hydraulic oil enters the rodless cavity of the synchronous large oil cylinder and pushes the piston rod of the synchronous large oil cylinder to extend outwards and push the piston rod of the synchronous small oil cylinder to retract, gas in the rodless cavity of the synchronous small oil cylinder is discharged through a parallel oil pipe connected with the serial oil pipe, then the reversing valve is powered off, the second oil pipe is communicated with the oil outlet pipe, the first oil pipe is communicated with the oil inlet pipe, the hydraulic oil enters the rodless cavity of the synchronous small oil cylinder from the parallel oil pipe again through the serial oil pipe to conduct oil supplementing action, and the piston rod of the action oil cylinder is opened to control the self weight of the parallel oil pipe before all the steps are operated;
or, the hydraulic device is firstly used for enabling the piston rods of the synchronous small oil cylinder and the action oil cylinder to extend outwards through adjusting the output pressure of the system, and then stopping pressure output after the piston rods of the action oil cylinder extend outwards, the piston rods of the action oil cylinders retract due to the gravity of a connected platform and discharge gas in the rodless cavity of the action oil cylinder to an oil tank, then the pressure is recovered, a reversing valve is electrified, hydraulic oil enters the rodless cavity of the synchronous large oil cylinder from a second oil pipe through an oil inlet pipe, hydraulic oil can flow to an oil outlet pipe from a first oil pipe, the hydraulic oil enters the rodless cavity of the synchronous large oil cylinder and pushes the piston rods of the synchronous large oil cylinder, the piston rods of the synchronous large oil cylinder extend outwards and push the piston rods of the synchronous small oil cylinder to retract, the gas in the rodless cavity of the synchronous small oil cylinder is discharged through a parallel oil pipe, the reversing valve is in power failure, the first oil pipe is communicated with the oil inlet pipe, the hydraulic oil enters the rodless cavity of the synchronous small oil cylinder through the parallel oil pipe, and the stop valve before all the steps are operated to open.
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