CN113530905A - Walking hydraulic control valve for overhead working truck - Google Patents
Walking hydraulic control valve for overhead working truck Download PDFInfo
- Publication number
- CN113530905A CN113530905A CN202010301282.4A CN202010301282A CN113530905A CN 113530905 A CN113530905 A CN 113530905A CN 202010301282 A CN202010301282 A CN 202010301282A CN 113530905 A CN113530905 A CN 113530905A
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- Prior art keywords
- valve
- cavity
- hydraulic control
- spring
- control valve
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- 238000007789 sealing Methods 0.000 claims abstract description 54
- 230000002093 peripheral effect Effects 0.000 claims abstract description 8
- 230000000903 blocking effect Effects 0.000 claims description 8
- 239000010720 hydraulic oil Substances 0.000 description 11
- 239000003921 oil Substances 0.000 description 6
- 238000004891 communication Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000009434 installation Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
Images
Classifications
-
- 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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F11/00—Lifting devices specially adapted for particular uses not otherwise provided for
- B66F11/04—Lifting devices specially adapted for particular uses not otherwise provided for for movable platforms or cabins, e.g. on vehicles, permitting workmen to place themselves in any desired position for carrying out required operations
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Structural Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Multiple-Way Valves (AREA)
Abstract
The invention discloses a hydraulic control valve for overhead working truck, comprising: the valve comprises a valve shell component, a valve core shaft and a first spring. One end of the valve shell component is provided with a first cavity opening, one end of the valve shell component is closed, the inner wall of the valve shell component is provided with a sealing ring, and the outer peripheral surface of the valve shell component is provided with a second cavity opening. The valve core shaft passes through the first cavity opening, one end of the valve core shaft is positioned outside the first cavity opening, and the other end of the valve core shaft is positioned in the valve shell component. The valve core shaft is provided with an annular sealing part which is sealed with the inner wall of the valve shell component, the valve core shaft is provided with a first conical surface, and the first conical surface is provided with a groove. The interior of the valve shell assembly is axially divided into a first valve cavity, a second valve cavity and a third valve cavity, a first cavity opening is communicated with the first valve cavity, a second cavity opening is communicated with the second valve cavity, and the first valve cavity is communicated with the second valve cavity through a groove. The first spring is positioned in the third valve cavity and presses the bottoms of the valve core shaft and the valve shell assembly respectively. The device can control the high-altitude operation vehicle to uniformly and slowly descend.
Description
Technical Field
The invention relates to a walking hydraulic control valve of an overhead working truck.
Background
The aerial work platform is a movable aerial work product for serving aerial work, equipment installation, maintenance and the like in various industries. The construction safety can be greatly improved by using the aerial work platform, and the equipment has wide application. During the use process, the operation stability of the aerial work platform on the ramp is very important, and the walking hydraulic control valve is an important part for controlling the walking of the ramp of the aerial work platform. The conventional aerial work platform has the defects of high downhill speed and nonuniform speed due to the fact that a walking hydraulic control valve cannot slowly and uniformly control the flow of hydraulic oil in the downhill process.
Disclosure of Invention
The invention aims to overcome the defects of high downhill speed and uneven speed of an aerial work platform in the prior art, and provides a hydraulic control valve for walking of an aerial work vehicle, which can enable the aerial work vehicle to move slowly and uniformly.
The invention solves the technical problems through the following technical scheme:
the utility model provides an overhead working truck hydraulic control valve that walks which characterized in that, it includes:
the valve shell assembly is of a sleeve structure, one end of the valve shell assembly is provided with a first cavity, the other end of the valve shell assembly is closed, the inner wall of the valve shell assembly is provided with a sealing ring, and the outer peripheral surface of the valve shell assembly is provided with a second cavity;
the valve core shaft penetrates through the first cavity opening, one end of the valve core shaft is positioned outside the first cavity opening, the other end of the valve core shaft is positioned in the valve casing assembly, an annular sealing part is arranged on the valve core shaft and is sealed with the inner wall of the valve casing assembly, a first conical surface is arranged on the valve core shaft, a groove is formed in the first conical surface, the valve core shaft can divide the interior of the valve casing assembly into a first valve cavity, a second valve cavity and a third valve cavity along the axial direction, the first cavity opening is communicated with the first valve cavity, the second cavity opening is communicated with the second valve cavity, and the first valve cavity is communicated with the second valve cavity through the groove;
the first spring is located in the third valve cavity, one end of the first spring is pressed on the valve plug shaft, the other end of the first spring is pressed on the bottom of the valve shell component, and the first conical surface is pressed on the sealing ring by the first spring.
Preferably, the first tapered surface is provided with a groove, and the first valve cavity and the second valve cavity are communicated through the groove.
Preferably, the sealing ring has a second tapered surface, and the first tapered surface is attached to the second tapered surface.
Preferably, the valve housing subassembly includes a valve casing and a valve barrel, the valve casing with the valve barrel is along axial looks butt, first accent is located the one end of valve barrel, the sealing ring is located the other end of valve barrel, high altitude construction car walking hydraulic control valve still includes second spring and first gasket, first gasket cover in the valve core is epaxial, the one end of second spring can press in first gasket, the other end of second spring can press in the one end of sealing ring, the second spring can with the valve barrel presses in the valve casing.
Preferably, the spring constant of the second spring is much smaller than the spring constant of the first spring.
Preferably, the valve housing is provided with a balance hole, and the balance hole is communicated with the third valve cavity.
Preferably, the third cavity has a blocking surface therein, and the blocking surface can block the annular sealing part from moving towards the direction of compressing the first spring.
Preferably, the annular sealing part is provided with a first sealing groove, the hydraulic control valve for overhead working truck traveling further comprises a first sealing ring, and the first sealing ring is installed in the first sealing groove.
Preferably, a second sealing groove is formed in the outer peripheral surface of the valve sleeve, the hydraulic control valve for overhead working truck traveling further comprises a second sealing ring, and the second sealing ring is installed in the second sealing groove.
Preferably, the outer peripheral face of valve casing has external screw thread, bellied spacing ring and third seal groove, the inner wall of third seal groove with the terminal surface coincidence of spacing ring, the external screw thread with the spacing ring is located the both sides of third seal groove, the external screw thread is compared the spacing ring is close to the valve barrel, high altitude construction car walking hydraulic control valve still includes the third sealing washer, the third sealing washer install in the third seal groove.
Preferably, a fourth sealing groove is formed in one end, located outside the first cavity opening, of the valve core shaft, and the hydraulic control valve for overhead working truck traveling further comprises a fourth sealing ring which is installed in the fourth sealing groove.
On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.
The positive progress effects of the invention are as follows: the walking hydraulic control valve is used for being connected with an actuating mechanism of the overhead working truck, and the first cavity opening and the second cavity opening can be communicated with each other by pressing the valve core shaft, so that the effect of controlling the overhead working truck to descend uniformly and slowly is achieved.
Drawings
Fig. 1 is a schematic perspective view of a hydraulic control valve for overhead working truck traveling in a preferred embodiment of the present invention.
Fig. 2 is a sectional view showing the internal structure of a hydraulic control valve for traveling of an overhead working truck in accordance with a preferred embodiment of the present invention.
Fig. 3 is a schematic structural view of a valve plug shaft in a preferred embodiment of the invention.
FIG. 4 is a hydraulic schematic diagram of a hydraulic control valve for overhead working truck travel applied to an overhead working platform in a preferred embodiment of the present invention.
Description of reference numerals:
Stop surface 113
Second conical surface 123
Fourth seal groove 230
Mounting shaft 240
Second gasket 700
Detailed Description
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.
1-3 illustrate an aerial lift vehicle travel hydraulic control valve comprising: a valve housing assembly 100, a valve plug shaft 200, and a first spring 300. The valve housing assembly 100 is of a sleeve structure, one end of the valve housing assembly 100 is provided with a first cavity 121, the other end of the valve housing assembly 100 is closed, the inner wall of the valve housing assembly 100 is provided with a sealing ring 122, and the outer peripheral surface of the valve housing assembly 100 is provided with a second cavity 111. The valve plug shaft 200 passes through the first bore 121, with one end of the valve plug shaft 200 being positioned outside the first bore 121 and the other end of the valve plug shaft 200 being positioned within the valve housing assembly 100. The valve plug shaft 200 has an annular sealing portion 210, the annular sealing portion 210 seals with an inner wall of the valve housing assembly 100, the valve plug shaft 200 has a first tapered surface 220, and the first tapered surface 220 has a groove 221. The spool shaft 200 can axially divide the interior of the valve housing assembly 100 into a first valve chamber 130, a second valve chamber 140, and a third valve chamber 150, the first port 121 communicating with the first valve chamber 130, the second port 111 communicating with the second valve chamber 140, and the first valve chamber 130 communicating with the second valve chamber 140 via the groove 221. The first spring 300 is positioned within the third valve cavity 150 such that one end of the first spring 300 presses against the valve plug shaft 200 and the other end of the first spring 300 presses against the bottom of the valve housing assembly 100, and the first spring 300 presses the first tapered surface 220 against the sealing ring 122.
The walking hydraulic control valve of the overhead working truck needs to be matched with a valve seat for use and is arranged in a valve hole of the valve seat. The control valve comprises a pilot port, an inlet oil port and an oil outlet port, wherein the first cavity port 121 and the second cavity port 111 are the inlet oil port or the oil outlet port, and the pilot port is connected to the outer end of the valve plug shaft 200. When the pilot port is fed, the spool shaft 200 is pushed to move, so that the first port 121 and the second port 111 are communicated with each other, and hydraulic oil can freely flow between the first valve chamber 130 and the second valve chamber 140.
As shown in fig. 4, the hydraulic control valves for overhead working truck traveling are generally used in pairs, the second port 111 of the left control valve communicates with the pilot hole of the right control valve, the first port 121 of the left control valve communicates with one end of the actuator, and the first port 121 of the right control valve communicates with the other end of the actuator. When using the control valve to promote the actuator to remove, by the second chamber mouth 111 oil feed of left side control valve, hydraulic oil divide into two the tunnel this moment: one path of hydraulic oil enters the second valve cavity 140 of the left control valve, slowly and uniformly enters the first valve cavity 130 through the groove 221, and enters one end of the actuating mechanism through the first cavity opening 121; the other path of hydraulic oil enters a pilot port of the right control valve, the valve core shaft 200 is pushed to move, so that the first valve cavity 130 and the second valve cavity 140 are communicated with each other, and the hydraulic oil at the other end of the actuating mechanism flows back to the first cavity port 121 and the second cavity port 111 of the right control valve, so that the high-altitude operation vehicle can move slowly and uniformly.
The mechanism can also realize the quick braking effect of the overhead working truck. When the aerial platform vehicle stops moving, the first conical surfaces 220 in the left control valve and the right control valve are pressed on the sealing ring 122, and at the moment, the left control valve and the right control valve are both in a basic sealing state. The flow speed of hydraulic oil in the actuating mechanism of the high-altitude operation vehicle is rapidly reduced, a reverse acting force is formed, the high-altitude operation vehicle is prevented from continuously moving, and therefore the purpose of rapid braking is achieved. In addition, when the driving mechanism of the high-altitude operation vehicle stops moving, the first valve cavity 130 and the second valve cavity 140 are always provided with the mutually communicated groove 221, so that the oil pressure at two ends of the actuating mechanism of the high-altitude operation vehicle can be always kept balanced. The operator pushes the high-altitude operation vehicle manually, and the high-altitude operation vehicle can also move slowly. That is, the position of the aerial work platform can be manually moved in the case where the drive mechanism is out of order or the position of the aerial work platform needs to be finely adjusted.
In order to improve the sealing performance between the sealing ring 122 and the first tapered surface 220, the sealing ring 122 has a second tapered surface 123, and the first tapered surface 220 and the second tapered surface 123 are attached to each other.
In this embodiment, the valve housing assembly 100 includes a valve housing 110 and a valve housing 120, wherein the valve housing 110 and the valve housing 120 axially abut against each other. The first chamber port 121 is located at one end of the valve housing 120 and the packing ring 122 is located at the other end of the valve housing 120. The hydraulic control valve for overhead working truck traveling further includes a second spring 400 and a first washer 500. The first shim 500 is fitted over the valve core shaft 200, one end of the second spring 400 can be pressed against the first shim 500, the other end of the second spring 400 can be pressed against one end of the seal ring 122, and the second spring 400 can press the valve housing 120 against the valve housing 110. The coupling structure of the valve housing 120, the second spring 400 and the first gasket 500 can further facilitate the communication between the first valve chamber 130 and the second valve chamber 140. That is, when the pilot port is not activated, the hydraulic oil introduced into the second valve chamber 140 can push the valve sleeve 120 to move in a direction of compressing the second spring 400, thereby communicating the first valve chamber 130 and the second valve chamber 140 with each other.
In this embodiment, the elastic coefficient of the second spring 400 is much smaller than that of the first spring 300.
In addition, the valve housing 110 is opened with a balance hole 112, and the balance hole 112 communicates with the third valve chamber 150. The balance hole 112 is mainly used to balance the pressure in the third valve chamber 150, so as to prevent the third valve chamber 150 from being pressurized too much, which results in the valve core shaft 200 not moving.
In this embodiment, one end of the valve shaft 200 has an installation shaft 240, and the first spring 300 is sleeved on the installation shaft 240. To control the amount of compression of the first spring 300, the mounting shaft 240 is fitted with a second washer 700, and the first spring 300 is pressed against the second washer 700.
Meanwhile, in order to prevent the communication port between the second valve chamber 140 and the third valve chamber 150 from being too large due to the excessive pressure of the pilot port, so that the flow rate of the hydraulic oil in the hydraulic system is too large or unstable, a blocking surface 113 is provided in the third chamber, and the blocking surface 113 can block the annular sealing portion 210 from moving in a direction of compressing the first spring 300. That is, when the annular seal portion 210 abuts against the blocking surface 113, the communication port between the second valve chamber 140 and the third valve chamber 150 is opened to the maximum.
In this embodiment, the annular sealing portion 210 has a first sealing groove 211, and the hydraulic control valve for overhead working truck traveling further includes a first sealing ring 610, and the first sealing ring 610 is installed in the first sealing groove 211.
In addition, the outer circumferential surface of the valve housing 120 is provided with a second sealing groove 124, the hydraulic control valve for traveling of the aerial lift truck further includes a second sealing ring 620, and the second sealing ring 620 is installed in the second sealing groove 124. The second sealing ring 620 is mainly used to ensure that the valve housing 120 and the valve hole of the valve seat are in a sealed state, i.e., the second valve chamber 140 and the first valve chamber 130 cannot be communicated with each other through the gap between the valve housing 120 and the valve hole.
The valve housing 110 has an external thread 114, a raised stopper ring 115, and a third seal groove 116 on its outer circumferential surface. The inner wall of the third sealing groove 116 coincides with the end surface of the stop collar 115, the external thread 114 and the stop collar 115 are located on both sides of the third sealing groove 116, and the external thread 114 is closer to the valve sleeve 120 than the stop collar 115. The hydraulic control valve for overhead working truck travel further comprises a third seal ring 630, and the third seal ring 630 is mounted in the third seal groove 116. The third sealing ring 630 is mainly used to ensure that the hydraulic oil in the second valve chamber 140 cannot leak out of the valve hole of the valve seat.
The end of the spool 200, which is located outside the first opening 121, is provided with a fourth sealing groove 230, and the hydraulic control valve for overhead working truck traveling further comprises a fourth sealing ring 640, and the fourth sealing ring 640 is installed in the fourth sealing groove 230. The fourth seal ring 640 is used to ensure that hydraulic oil in the pilot port cannot enter the second valve chamber 140.
While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.
Claims (10)
1. The utility model provides an overhead working truck hydraulic control valve that walks which characterized in that, it includes:
the valve shell assembly is of a sleeve structure, one end of the valve shell assembly is provided with a first cavity, the other end of the valve shell assembly is closed, the inner wall of the valve shell assembly is provided with a sealing ring, and the outer peripheral surface of the valve shell assembly is provided with a second cavity;
the valve core shaft penetrates through the first cavity opening, one end of the valve core shaft is positioned outside the first cavity opening, the other end of the valve core shaft is positioned in the valve casing assembly, an annular sealing part is arranged on the valve core shaft and is sealed with the inner wall of the valve casing assembly, a first conical surface is arranged on the valve core shaft, a groove is formed in the first conical surface, the valve core shaft can divide the interior of the valve casing assembly into a first valve cavity, a second valve cavity and a third valve cavity along the axial direction, the first cavity opening is communicated with the first valve cavity, the second cavity opening is communicated with the second valve cavity, and the first valve cavity is communicated with the second valve cavity through the groove;
the first spring is located in the third valve cavity, one end of the first spring is pressed on the valve plug shaft, the other end of the first spring is pressed on the bottom of the valve shell component, and the first conical surface is pressed on the sealing ring by the first spring.
2. The overhead working truck travel hydraulic control valve of claim 1 wherein the seal ring has a second tapered surface thereon, the first tapered surface abutting the second tapered surface.
3. The overhead working vehicle travel hydraulic control valve of claim 1 wherein the valve housing assembly includes a valve housing and a valve housing, the valve housing and the valve housing axially abutting each other, the first port is located at one end of the valve housing, the seal ring is located at the other end of the valve housing, the overhead working vehicle travel hydraulic control valve further including a second spring and a first washer, the first washer being fitted over the spool shaft, one end of the second spring being capable of pressing against the first washer, the other end of the second spring being capable of pressing against one end of the seal ring, the second spring being capable of pressing the valve housing against the valve housing.
4. The overhead working truck travel hydraulic control valve of claim 3 wherein the second spring has a spring constant that is substantially less than the spring constant of the first spring.
5. The overhead working truck travel hydraulic control valve of claim 3 wherein the valve housing has a balancing port formed therein, the balancing port communicating with the third valve chamber.
6. The overhead working truck travel hydraulic control valve of claim 3 wherein the third chamber has a blocking surface therein, the blocking surface being capable of blocking movement of the annular seal in a direction to compress the first spring.
7. The overhead working truck travel hydraulic control valve of claim 3 wherein the annular seal portion defines a first seal groove, the overhead working truck travel hydraulic control valve further comprising a first seal ring mounted within the first seal groove.
8. The overhead working truck travel hydraulic control valve of claim 3 wherein the valve housing has a second seal groove formed in an outer peripheral surface thereof, the overhead working truck travel hydraulic control valve further comprising a second seal ring mounted in the second seal groove.
9. The overhead working truck traveling hydraulic control valve according to claim 3, wherein an external thread, a raised limit ring and a third seal groove are provided on an outer peripheral surface of the valve housing, an inner wall of the third seal groove coincides with an end surface of the limit ring, the external thread and the limit ring are located on both sides of the third seal groove, the external thread is closer to the valve housing than the limit ring, and the overhead working truck traveling hydraulic control valve further comprises a third seal ring installed in the third seal groove.
10. The overhead working truck travel hydraulic control valve of claim 1, wherein an end of the spool shaft outside the first bore has a fourth seal groove, the overhead working truck travel hydraulic control valve further comprising a fourth seal ring mounted in the fourth seal groove.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010301282.4A CN113530905A (en) | 2020-04-16 | 2020-04-16 | Walking hydraulic control valve for overhead working truck |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010301282.4A CN113530905A (en) | 2020-04-16 | 2020-04-16 | Walking hydraulic control valve for overhead working truck |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113530905A true CN113530905A (en) | 2021-10-22 |
Family
ID=78120280
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010301282.4A Pending CN113530905A (en) | 2020-04-16 | 2020-04-16 | Walking hydraulic control valve for overhead working truck |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113530905A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103470815A (en) * | 2013-09-30 | 2013-12-25 | 常德中联重科液压有限公司 | Balance valve |
| CN203532383U (en) * | 2013-10-14 | 2014-04-09 | 徐州重型机械有限公司 | Balance valve device |
| CN105971963A (en) * | 2016-07-19 | 2016-09-28 | 宁波文泽机电技术开发有限公司 | Flow type balancing valve |
| CN108278240A (en) * | 2018-01-24 | 2018-07-13 | 陈艳艳 | A kind of automatic damping adjusting valve |
| KR20190137400A (en) * | 2018-06-01 | 2019-12-11 | 에스에프하이월드 주식회사 | Proportional pressure-reducing valve with spool having improved shape of land portion |
-
2020
- 2020-04-16 CN CN202010301282.4A patent/CN113530905A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103470815A (en) * | 2013-09-30 | 2013-12-25 | 常德中联重科液压有限公司 | Balance valve |
| CN203532383U (en) * | 2013-10-14 | 2014-04-09 | 徐州重型机械有限公司 | Balance valve device |
| CN105971963A (en) * | 2016-07-19 | 2016-09-28 | 宁波文泽机电技术开发有限公司 | Flow type balancing valve |
| CN108278240A (en) * | 2018-01-24 | 2018-07-13 | 陈艳艳 | A kind of automatic damping adjusting valve |
| KR20190137400A (en) * | 2018-06-01 | 2019-12-11 | 에스에프하이월드 주식회사 | Proportional pressure-reducing valve with spool having improved shape of land portion |
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