CN216241552U - Pumping hydraulic system and wet spraying machine - Google Patents
Pumping hydraulic system and wet spraying machine Download PDFInfo
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- CN216241552U CN216241552U CN202122230003.2U CN202122230003U CN216241552U CN 216241552 U CN216241552 U CN 216241552U CN 202122230003 U CN202122230003 U CN 202122230003U CN 216241552 U CN216241552 U CN 216241552U
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Abstract
The utility model provides a pumping hydraulic system and a wet spraying machine, wherein the pumping hydraulic system comprises an oil tank, a first oil pump, a second oil pump and a controller; an oil inlet of the first oil pump is communicated with the oil tank, an oil outlet of the first oil pump is connected with a tilt cylinder through a pumping valve block, and the first oil pump is provided with a feedback oil port; an oil inlet of the second oil pump is communicated with the oil tank, and an oil outlet of the second oil pump is connected with the feedback oil port through the first valve, the second valve and the pressure stabilizing unit; the controller is simultaneously electrically connected with the pumping valve block, the first valve and the second valve. When the small-displacement pumping is carried out, the electromagnetic valve of the first valve is electrified while the tilt cylinder reversing electromagnetic valve in the pumping valve block is electrified, no pressure oil flows to the feedback oil port, and the first oil pump works at the maximum displacement, so that the tilt cylinder is reversed in place and is free of clamping stagnation when the small-displacement pumping is carried out. The pumping hydraulic system does not need an energy accumulator, so that the failure rate is reduced, and the maintenance cost is also reduced.
Description
Technical Field
The utility model relates to the field of engineering machinery, in particular to a pumping hydraulic system and a wet spraying machine.
Background
The pumping hydraulic system is a main working mechanism of the wet spraying machine and is responsible for sucking and pressurizing concrete from a hopper, pumping the concrete into a conveying pipe and continuously conveying the concrete to a pouring site through the conveying pipe. In a pumping hydraulic system, a pumping main oil cylinder and a swinging oil cylinder are two main power output units, power of the pumping main oil cylinder and the swinging oil cylinder is derived from an oil pump, and a transmission medium is pressure oil.
Compared with a pumping main oil cylinder, the swing oil cylinder outputs smaller power. Therefore, when the swing oil cylinder works, the displacement of the pressure oil in the oil pump is small, so that the swing oil cylinder is easy to block during reversing. In order to enable the swing oil cylinder to be free from clamping stagnation during reversing, an energy accumulator is often arranged in an existing pumping hydraulic system, peak pressure impact generated during reversing of a hydraulic control valve of a pumping main oil cylinder is absorbed by the energy accumulator, and stored pressure oil is used for pushing the swing oil cylinder to reverse.
However, the accumulator is sensitive to the cleanliness of oil, and is prone to failure, so that the normal operation of a pumping hydraulic system is affected, and meanwhile, the maintenance cost is increased.
SUMMERY OF THE UTILITY MODEL
To solve the problems in the prior art, it is an object of the present invention to provide a pumping hydraulic system.
The utility model provides the following technical scheme:
a pumping hydraulic system comprises an oil tank, a first oil pump, a second oil pump and a controller;
an oil inlet of the first oil pump is communicated with the oil tank, an oil outlet of the first oil pump is connected with a tilt cylinder through a pumping valve block, the first oil pump is provided with a feedback oil port, and the displacement of the first oil pump is increased along with the reduction of the oil quantity of the feedback oil port;
an oil inlet of the second oil pump is communicated with the oil tank, an oil outlet of the second oil pump is connected with the feedback oil port through a first valve, a second valve and a pressure stabilizing unit, the oil outlet of the second oil pump, the pressure stabilizing unit, the second valve and the first valve are sequentially connected, and the second valve is used for regulating pressure oil flowing to the feedback oil port;
the controller is simultaneously electrically connected with the pumping valve block, the first valve and the second valve, and the controller controls the first valve to cut off pressure oil flowing to the feedback oil port when the tilt cylinder is reversed.
As a further alternative to the pumping hydraulic system, the pressure stabilizing unit includes a throttle valve and a pressure reducing valve, and the throttle valve is located between the second oil pump and the pressure reducing valve.
As a further alternative to the pumping hydraulic system, the second valve employs a proportional pressure reducing valve.
As a further alternative to the pumping hydraulic system, the oil outlet of the first oil pump is connected with a master cylinder through the pumping valve block.
As a further alternative to the pumping hydraulic system, the oil outlet of the second oil pump is also used for connecting a stirring motor.
As a further alternative to the pumping hydraulic system, the first oil pump employs an inverse proportional pilot-controlled pump.
As a further alternative to the pumping hydraulic system, the first valve is a reversing valve.
Another object of the present invention is to provide a wet blasting machine.
The utility model provides the following technical scheme:
a wet spraying machine comprises the pumping hydraulic system.
The embodiment of the utility model has the following beneficial effects:
the second oil pump takes out the pressure oil in the oil tank, forms stable pressure oil after the pressure stabilizing unit, and flows through the second valve and the first valve in sequence. When the tilt cylinder is not reversed, the controller controls the second valve to adjust the pressure oil flowing to the feedback oil port, so that the first oil pump conveys the pressure oil in the oil tank into the tilt cylinder through the pumping valve block at a small displacement, and a small driving force is provided for the tilt cylinder. When the swing cylinder is reversed, the controller controls the first valve to cut off pressure oil flowing to the feedback oil port, no pressure oil flows through the feedback oil port, namely the oil quantity of the feedback oil port is zero, the displacement of the first oil pump is enabled to be maximum, and the driving force borne by the swing cylinder is also enabled to be maximum, so that the reversing of the swing cylinder is ensured to be free of clamping stagnation. The pumping hydraulic system does not need an energy accumulator, so that the failure rate is reduced, and the maintenance cost is also reduced.
In order to make the aforementioned objects, features and advantages of the present invention more comprehensible and comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
Fig. 1 is a schematic diagram illustrating an overall structure of a pumping hydraulic system provided in embodiment 1 of the present invention;
fig. 2 shows a schematic diagram of the overall structure of a pumping hydraulic system provided in embodiment 2 of the present invention.
Description of the main element symbols:
100-oil tank; 200-a first oil pump; 300-a second oil pump; 310-a first valve; 320-a second valve; 330-a voltage stabilizing unit; 331-a throttle valve; 332-a pressure relief valve; 400-a controller; 500-pumping a valve block; 600-tilt cylinder; 700-master cylinder.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.
It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the templates herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
Example 1
Referring to fig. 1, the present embodiment provides a pumping hydraulic system, which is applied to engineering machinery for conveying concrete, such as a wet spraying machine and a pump truck. The pumping hydraulic system includes an oil tank 100, a first oil pump 200, a pumping valve block 500, a tilt cylinder 600, a second oil pump 300, and a controller 400.
Specifically, pressure oil is stored in the oil tank 100, and the oil tank 100 is connected to oil inlets of the first oil pump 200 and the second oil pump 300 through a three-way pipe.
Specifically, an oil outlet of the first oil pump 200 is connected with the tilt cylinder 600 through a pumping valve block 500, and a tilt cylinder reversing solenoid valve is arranged in the pumping valve block 500. The first oil pump 200 operates to pump out the pressurized oil in the oil tank 100 and then supply the pumped oil to the tilt cylinder 600. In this process, the pumping valve block 500 controls the flowing direction of the pressure oil in the tilt cylinder 600 by electrifying the tilt cylinder reversing solenoid valve, thereby changing the direction of the power output by the tilt cylinder 600.
In addition, the first oil pump 200 also has a feedback port. The smaller the amount of oil flowing through the feedback port, the larger the displacement of the first oil pump 200. When the feedback port has no pressure oil, the displacement of the first oil pump 200 reaches the maximum.
Specifically, an oil outlet of the second oil pump 300 is connected to a feedback oil port of the first oil pump 200, a first valve 310, a second valve 320 and a pressure stabilizing unit 330 are arranged between the oil outlet of the second oil pump 300 and the feedback oil port of the first oil pump 200, and the oil outlet of the second oil pump 300, the pressure stabilizing unit 330, the second valve 320 and the first valve 310 are sequentially connected.
When the second oil pump 300 operates, the pressure oil in the oil tank 100 is pumped out, sequentially flows through the pressure stabilizing unit 330, the second valve 320 and the first valve 310, and is then delivered to the feedback port, so as to control the displacement of the first oil pump 200.
Specifically, the controller 400 is electrically connected to both the pumping valve block 500 and the first and second valves 310 and 320. Wherein the pumping valve block 500 changes the flow direction of the pressure oil in the tilt cylinder 600 under the control of the controller 400. While the flow direction of the pressure oil is changed, the controller 400 energizes the solenoid valve of the first valve 310, and controls the first valve 310 to cut off the pressure oil flowing to the feedback port.
The second oil pump 300 pumps the pressure oil in the oil tank 100, and the pressure oil passes through the pressure stabilizing unit 330 to form stable pressure oil, and the pressure oil sequentially flows through the second valve 320 and the first valve 310 to enter the feedback port. When the tilt cylinder 600 is not reversed, the controller 400 controls the second valve 320 to regulate the pressure oil flowing to the feedback port, so that the first oil pump 200 delivers the pressure oil in the oil tank 100 to the tilt cylinder 600 through the pumping valve block 500 at a small displacement, and a small driving force is provided for the tilt cylinder 600. When the tilt cylinder 600 is reversed, the controller 400 controls the first valve 310 to cut off the pressure oil flowing to the feedback port, so that no pressure oil flows through the feedback port, that is, the oil amount of the feedback port is zero, the displacement of the first oil pump 200 is maximized, and the driving force applied to the tilt cylinder 600 is maximized, thereby ensuring that the tilt cylinder 600 is reversed without clamping stagnation. The pumping hydraulic system does not need an energy accumulator, so that the failure rate is reduced, and the maintenance cost is also reduced.
Example 2
Referring to fig. 2, the present embodiment provides a pumping hydraulic system, which is applied to engineering machinery for conveying concrete, such as a wet spraying machine and a pump truck. The pumping hydraulic system includes an oil tank 100, a first oil pump 200, a pumping valve block 500, a master cylinder 700, a tilt cylinder 600, a second oil pump 300, and a controller 400.
Specifically, the oil tank 100 stores therein pressurized oil. The oil tank 100 is respectively connected with oil inlets of the first oil pump 200 and the second oil pump 300 through a three-way pipe, and simultaneously supplies oil to the first oil pump 200 and the second oil pump 300.
Specifically, the oil outlet of the first oil pump 200 is connected to the master cylinder 700 and the tilt cylinder 600 through the pumping valve block 500, respectively. The first oil pump 200 is operated to pump out pressure oil in the oil tank 100 and then send the pressure oil to the master cylinder 700 or the tilt cylinder 600. In this process, the pumping valve block 500 controls the flow direction of the pressure oil.
When the pumping valve block 500 controls the pressure oil to flow to the master cylinder 700, a driving force is output from the master cylinder 700. When the pumping valve block 500 controls the pressure oil to flow to the tilt cylinder 600, the driving force is output by the tilt cylinder 600. With the pumping valve block 500, only one first oil pump 200 is required to supply oil to the master cylinder 700 and the tilt cylinder 600.
In addition, the pumping valve block 500 also regulates and controls the flowing direction of the pressure oil in the tilt cylinder 600, so as to change the direction of the output power of the tilt cylinder 600.
In the present embodiment, the first oil pump 200 is an inverse proportional hydraulic control pump having a feedback port. The smaller the amount of oil flowing through the feedback port, the larger the displacement of the first oil pump 200. In particular, when the feedback port has no pressure oil, the displacement of the first oil pump 200 reaches the maximum.
When the first oil pump 200 supplies oil to the master cylinder 700, the displacement of the first oil pump 200 is large, and the driving force output from the master cylinder 700 is also large. When the first oil pump 200 supplies oil to the tilt cylinder 600 and the tilt cylinder 600 is not reversed, the displacement of the first oil pump 200 is small and the driving force output by the tilt cylinder 600 is also small.
Specifically, an oil outlet of the second oil pump 300 is connected to a feedback oil port of the first oil pump 200, and a first valve 310 is disposed between the oil outlet of the second oil pump 300 and the feedback oil port of the first oil pump 200. The second oil pump 300 pumps the pressure oil in the oil tank 100 during operation, and delivers the pressure oil to the feedback port through the first valve 310, thereby controlling the displacement of the first oil pump 200.
Specifically, the controller 400 is electrically connected to both the pumping valve block 500 and the first valve 310. The pumping valve block 500 flows the pressure oil to the master cylinder 700 or the tilt cylinder 600 under the control of the controller 400. Specifically, when the pressure oil flows to the tilt cylinder 600 and the tilt cylinder 600 is reversed, the controller 400 controls the pumping valve block 500 to change the flow direction of the pressure oil in the tilt cylinder 600 and controls the first valve 310 to cut off the pressure oil flowing to the feedback port.
When the tilt cylinder 600 works and is not reversed, the oil quantity of the feedback oil port is large, the first oil pump 200 conveys the pressure oil in the oil tank 100 into the tilt cylinder 600 through the pumping valve block 500 with small displacement, and small driving force is provided for the tilt cylinder 600. When the tilt cylinder 600 is reversed, the controller 400 controls the first valve 310 to cut off the pressure oil flowing to the feedback port, so that no pressure oil flows through the feedback port, that is, the oil amount of the feedback port is zero, the displacement of the first oil pump 200 is maximized, and the driving force applied to the tilt cylinder 600 is maximized, thereby ensuring that the tilt cylinder 600 is reversed without clamping stagnation and can be reversed in place. The pumping hydraulic system does not need an energy accumulator, so that the failure rate is reduced, and the maintenance cost is also reduced.
In the present embodiment, the first valve 310 is a reversing valve. In another embodiment of the present application, the first valve 310 may also be a shut-off valve.
Further, under the condition that the direction change of the tilt cylinder 600 is not considered, the displacement of the first oil pump 200 when supplying oil to the master cylinder 700 and the tilt cylinder 600 still varies according to the actual requirement, in order to meet the requirement, a second valve 320 is further arranged between the oil outlet of the second oil pump 300 and the feedback oil port of the first oil pump 200, and the second valve 320 is electrically connected with the controller 400.
In the present embodiment, the second valve 320 employs a proportional pressure reducing valve, and the proportional pressure reducing valve is located between the oil outlet of the second oil pump 300 and the first valve 310. When the proportional pressure reducing valve is used, the controller 400 controls the current of the electromagnetic coil in the proportional pressure reducing valve so as to control the opening degree of the valve port of the proportional pressure reducing valve. The larger the current in the proportional pressure reducing valve is, the larger the opening degree of the valve port is, so that the oil amount at the feedback oil port is larger, and further the displacement of the first oil pump 200 is smaller.
Further, the oil amount of the feedback port is also influenced by the oil pressure at the second oil pump 300 while being controlled by the opening degree of the valve port of the second valve 320. In order to make the control of the displacement of the first oil pump 200 by the controller 400 more accurate, a pressure stabilizing unit 330 is further provided between the oil outlet of the second oil pump 300 and the second valve 320.
After the pressure oil discharged from the second oil pump 300 passes through the pressure stabilizing unit 330, the pressure tends to be stable, so that the influence of the oil pressure change at the second oil pump 300 on the oil amount of the feedback oil port is eliminated as much as possible.
In the present embodiment, the pressure stabilizing unit 330 is composed of a throttle valve 331 and a pressure reducing valve 332. The throttle 331 is located between the second oil pump 300 and the pressure reducing valve 332, and the pressure oil discharged from the second oil pump 300 passes through the throttle 331 and the pressure reducing valve 332 in this order to become stable pressure oil.
Further, the second oil pump 300 is a stirring gear pump, and is mainly used for supplying oil to a stirring motor on the wet jet machine. The oil outlet of the second oil pump 300 is connected to a three-way pipe, and is connected to the stirring motor and the throttle valve 331 through the three-way pipe, and a pressure oil is branched off from an oil path to the stirring motor as an oil source for regulating and controlling the displacement of the first oil pump 200.
Through the arrangement, a hydraulic system on the wet spraying machine is effectively simplified, the structure is simple, and the manufacturing cost is low.
The three operating conditions of the pumping hydraulic system are as follows:
first, the controller 400 controls the pumping valve block 500 to change the flow direction of the pressure oil, so that the pressure oil, which originally flows into the tilt cylinder 600, flows into the master cylinder 700, and the master cylinder 700 outputs the driving force. At the same time, the controller 400 controls the current in the second valve 320 to decrease, so that the opening degree of the second valve 320 decreases, the amount of oil flowing through the feedback port decreases, and the displacement of the first oil pump 200 increases.
Second, the controller 400 controls the pumping valve block 500 to change the flow direction of the pressure oil, so that the pressure oil, which originally flows into the master cylinder 700, flows into the tilt cylinder 600, and the tilt cylinder 600 outputs the driving force. At the same time, the controller 400 controls the current in the second valve 320 to increase, so that the opening degree of the second valve 320 increases, the amount of oil flowing through the feedback port increases, and the displacement of the first oil pump 200 decreases.
Third, when the pressure oil flows into the tilt cylinder 600 and the tilt cylinder 600 needs to be reversed, the controller 400 controls the pumping valve block 500 to change the flow direction of the pressure oil in the tilt cylinder 600, so that the direction of the output driving force of the tilt cylinder 600 is changed. Meanwhile, the controller 400 controls the first valve 310 to cut off the pressure oil flowing to the feedback port, so that the displacement of the first oil pump 200 is maximized, and the tilt cylinder 600 is ensured to be reversed without jamming and in place.
The embodiment also provides a wet spraying machine which comprises the pumping hydraulic system.
In all examples shown and described herein, any particular value should be construed as merely exemplary, and not as a limitation, and thus other examples of example embodiments may have different values.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
The above examples are merely illustrative of several embodiments of the present invention, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the utility model. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.
Claims (8)
1. A pumping hydraulic system is characterized by comprising an oil tank, a first oil pump, a second oil pump and a controller;
an oil inlet of the first oil pump is communicated with the oil tank, an oil outlet of the first oil pump is connected with a tilt cylinder through a pumping valve block, the first oil pump is provided with a feedback oil port, and the displacement of the first oil pump is increased along with the reduction of the oil quantity of the feedback oil port;
an oil inlet of the second oil pump is communicated with the oil tank, an oil outlet of the second oil pump is connected with the feedback oil port through a first valve, a second valve and a pressure stabilizing unit, the oil outlet of the second oil pump, the pressure stabilizing unit, the second valve and the first valve are sequentially connected, and the second valve is used for regulating pressure oil flowing to the feedback oil port;
the controller is simultaneously electrically connected with the pumping valve block, the first valve and the second valve, and the controller controls the first valve to cut off pressure oil flowing to the feedback oil port when the tilt cylinder is reversed.
2. The pumped hydraulic system of claim 1, wherein the pressure regulator unit includes a throttle valve and a pressure relief valve, and the throttle valve is located between the second oil pump and the pressure relief valve.
3. The pumped hydraulic system of claim 1, wherein the second valve employs a proportional pressure reducing valve.
4. The pumped hydraulic system of claim 1, wherein a master cylinder is connected to the oil outlet of the first oil pump through the pumping valve block.
5. The pumped hydraulic system of claim 1, wherein the oil outlet of the second oil pump is further configured to connect to a blender motor.
6. The pumped hydraulic system of claim 1, wherein the first oil pump is an inverse proportional pilot operated pump.
7. The pumped hydraulic system of claim 1, wherein the first valve is a reversing valve.
8. Wet-spraying machine, characterized in that it comprises a pumped hydraulic system according to any one of claims 1 to 7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122230003.2U CN216241552U (en) | 2021-09-15 | 2021-09-15 | Pumping hydraulic system and wet spraying machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122230003.2U CN216241552U (en) | 2021-09-15 | 2021-09-15 | Pumping hydraulic system and wet spraying machine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216241552U true CN216241552U (en) | 2022-04-08 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122230003.2U Active CN216241552U (en) | 2021-09-15 | 2021-09-15 | Pumping hydraulic system and wet spraying machine |
Country Status (1)
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|---|---|
| CN (1) | CN216241552U (en) |
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2021
- 2021-09-15 CN CN202122230003.2U patent/CN216241552U/en active Active
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