CN111720380A - Hydraulic motor protection device for engineering machinery - Google Patents
Hydraulic motor protection device for engineering machinery Download PDFInfo
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- CN111720380A CN111720380A CN202010548053.2A CN202010548053A CN111720380A CN 111720380 A CN111720380 A CN 111720380A CN 202010548053 A CN202010548053 A CN 202010548053A CN 111720380 A CN111720380 A CN 111720380A
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- hydraulic motor
- communicated
- sleeve
- cavity
- protection device
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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
- F15B13/024—Pressure relief valves
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Servomotors (AREA)
Abstract
The invention relates to a hydraulic motor protection device for engineering machinery, which comprises: the valve comprises a valve body, a valve sleeve, a valve core, a first elastic part, an armature, a magnetic sleeve and a coil. The invention has the advantages that: the invention has the stopping function and the protection function, when the hydraulic motor is started, the coil is powered off, and the stopping function is realized at the moment, so that the flow at the inlet of the hydraulic motor cannot be shunted, and the hydraulic motor can be quickly started; when the hydraulic motor is operated and needs to play a role in protection, the coil of the hydraulic motor is electrified, so that the function of limiting the highest pressure of oil can be achieved; the elasticity of the second elastic piece can be adjusted by arranging the adjusting rod, so that the highest pressure of the oil is controlled, and when the oil in the hydraulic motor pipeline reaches the highest pressure, the effect of pressure relief is achieved; the invention has the advantages of high integration, compact volume, simple structure and low manufacturing cost.
Description
Technical Field
The invention relates to the field of hydraulic motors, in particular to a hydraulic motor protection device for engineering machinery.
Background
The hydraulic motor is an actuating element of a hydraulic system, converts the hydraulic pressure energy provided by a hydraulic pump into mechanical energy (torque and rotating speed) of an output shaft of the hydraulic motor, and is mainly applied to injection molding machinery, ships, lifting machines, engineering machinery, construction machinery, coal mine machinery, mining machinery, metallurgical machinery, ship machinery, petrochemical industry, port machinery and the like. In engineering machinery applications, such as excavators, cranes, overhead working vehicles and the like, hydraulic motors are mainly used for swing control and winch control, and in order to limit the maximum working pressure of the hydraulic motor, a protection device is usually arranged in a hydraulic oil path. The existing protection device performs overflow shunting when the pressure of the inlet of the hydraulic motor exceeds the limited pressure of the hydraulic motor, thereby playing a role of safety protection; although the existing protection device can limit the maximum working pressure of the hydraulic motor, the starting torque of the hydraulic motor in a static state is large, and when the hydraulic motor is started, the flow at the inlet of the hydraulic motor is also shunted, so that the starting speed is too slow, and the working efficiency is influenced.
Disclosure of Invention
In view of the above, it is desirable to provide a hydraulic motor protection device for construction machinery, which can automatically release pressure when the pressure in a hydraulic motor pipeline is too high, thereby preventing overload of the hydraulic motor due to too high pressure.
The invention discloses a hydraulic motor protection device for engineering machinery, which comprises:
the valve body is provided with a first containing cavity and a second containing cavity, the first containing cavity is communicated with the second containing cavity through a first channel and a first through hole, and the second containing cavity is communicated with the oil tank through a second channel;
the valve sleeve is cylindrical and is fixedly arranged at the first cavity of the valve body; the valve body is provided with an inlet T and an outlet P, the inlet T is communicated with a hydraulic motor, the outlet P is positioned on the side surface of the valve body and is communicated with an oil tank,
the valve core is arranged in the valve sleeve in a sliding mode and provided with a through second through hole, the second through hole is communicated with the inlet T and the first cavity, and the valve core can block the inlet T and the outlet P;
the first elastic piece is arranged between the valve core and the valve body, so that the valve core is abutted to the valve sleeve;
the control sleeve is located in the second containing cavity and is connected to the valve body in a sliding mode, an opening is formed in the control sleeve, the control sleeve is provided with a first working position and a second working position, when the control sleeve is located at the first working position, the opening is communicated with the first channel, and when the control sleeve is located at the second working position, the opening is communicated with the second channel.
In one embodiment, the hydraulic motor protection device for construction machinery further includes:
the magnetic conduction sleeve is fixedly connected to the upper end of the valve body;
the armature is arranged in the magnetic conduction sleeve in a sliding mode and is fixedly connected with the control sleeve;
a coil which is sleeved outside the magnetic conduction sleeve and can control the armature to move up and down,
when the coil is not electrified, the first opening of the control sleeve is communicated with the first channel, so that the second cavity is communicated with the first cavity, and oil cannot enter the first cavity; when the coil is electrified, the control sleeve and the armature move upwards synchronously, so that the first channel is cut off by the control sleeve, meanwhile, the second opening is communicated with the second channel, the second cavity is communicated with the oil tank through the second channel, the inlet T is communicated with the oil tank, along with the increase of the flow velocity of oil entering the first cavity from the inlet T, the oil can enable the valve core to overcome the elasticity of the first elastic piece to slide, and the inlet T is communicated with the outlet P.
In one embodiment, the hydraulic motor protection device for construction machinery further includes:
the adjusting rod penetrates through the magnetic sleeve and the armature and extends into the second containing cavity;
the spring seat is arranged at the end part of the adjusting rod;
the upper end of the second elastic piece is abutted with the spring seat;
the pilot valve core is fixedly arranged at the lower end of the second elastic part and is abutted against the first through hole, so that the first through hole can be closed.
In one embodiment, the adjusting rod is in threaded connection with the magnetic sleeve, and the adjusting rod can be moved up and down by rotating the adjusting rod, so that the elastic force of the second elastic piece on the pilot valve core is adjusted and controlled.
In one embodiment, the pilot valve core is conical, and a tip portion is inserted into the first through hole to close the first through hole.
In one embodiment, a first annular groove is formed in the valve body and is communicated with the first through groove.
In one embodiment, a second annular groove is provided on the valve body, and the second annular groove is communicated with the second through groove.
In one embodiment, two openings are arranged on the control sleeve, and the two openings are located on the same plane and can be communicated with the first annular groove or the second annular groove at the same time.
In one embodiment, a third elastic member is arranged between the armature and the magnetic conductive sleeve.
In one embodiment, the upper end of the armature is provided with a first inclined surface, the lower end of the magnetic sleeve is provided with a second inclined surface, and the first inclined surface is matched with the second inclined surface.
The invention has the advantages that:
1. the invention has the stopping function and the protection function, when the hydraulic motor is started, the coil is powered off, and the stopping function is realized at the moment, so that the flow at the inlet of the hydraulic motor cannot be shunted, and the hydraulic motor can be quickly started; when the hydraulic motor is operated and needs to play a role in protection, the coil of the hydraulic motor is electrified, so that the function of limiting the highest pressure of oil can be achieved;
2. the elasticity of the second elastic piece can be adjusted by arranging the adjusting rod, so that the highest pressure of the oil is controlled, and when the oil in the hydraulic motor pipeline reaches the highest pressure, the effect of pressure relief is achieved;
3. the invention has the advantages of high integration, compact volume, simple structure and low manufacturing cost.
Drawings
Fig. 1 is a sectional view of a hydraulic motor protection device for construction machinery according to the present invention;
fig. 2 is a working state diagram of a hydraulic motor protection device for construction machinery according to the present invention.
In the figure, the hydraulic motor protection device 100 for the construction machine, a valve body 10, a first chamber 11, a second chamber 12, a first passage 13, a first through hole 14, a first annular groove 15, a second annular groove 16, a second passage 17, a valve sleeve 20, an inlet T21, an outlet P22, a valve core 30, a second through hole 31, a first elastic member 40, a control sleeve 50, an opening 51, an armature 60, a third elastic member 61, a first inclined surface 62, a magnetic conductive sleeve 70, a second inclined surface 71, a coil 80, an adjusting rod 91, a spring seat 92, a second elastic member 93 and a pilot valve core 94.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It will be understood that when an element is referred to as being "mounted on" another element, it can be directly on the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present. When an element is referred to as being "secured to" another element, it can be directly secured to the other element or intervening elements may also be present.
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 invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "or/and" includes any and all combinations of one or more of the associated listed items.
As shown in fig. 1, the present invention discloses a hydraulic motor protection device 100 for construction machinery, which includes: the valve comprises a valve body 10, a valve sleeve 20, a valve core 30, a first elastic member 40, an armature 60, a magnetic conductive sleeve 70 and a coil 80. The valve body 10 is provided with a first containing cavity 11 and a second containing cavity 12, the first containing cavity 11 is communicated with the second containing cavity 12 through a first channel 13 and a first through hole 14, and the second containing cavity 12 is communicated with the oil tank through a second channel 17; the valve sleeve 20 is cylindrical and is fixedly arranged at the first cavity 11 of the valve body 10; the valve core 30 is slidably disposed in the valve housing 20 and has a through second through hole 31, the second through hole 31 is a damping hole, the second through hole 31 communicates with the inlet T21 and the first cavity 11, and the valve core 30 can block the inlet T21 from the outlet P22; the first elastic element 40 is arranged between the valve core 30 and the valve body 10, so that the valve core 30 abuts against the valve sleeve 20; the control sleeve 50 is located in the second cavity 12 and is slidably connected to the valve body 10, an opening 51 is formed in the control sleeve 50, the control sleeve 50 has a first working position and a second working position, with reference to fig. 1, when the control sleeve 50 is located in the first working position, the opening 51 is communicated with the first passage 13, with reference to fig. 2, when the control sleeve 50 is located in the second working position, the opening 51 is communicated with the second passage 17; the magnetic sleeve 70 is arranged on the upper part of the valve body 10 and is fixedly connected with the valve body 10; the armature 60 is fixedly connected with the control sleeve 50 and is slidably arranged in the magnetic conductive sleeve 70; the coil 80 is sleeved outside the flux sleeve 70 and can control the armature 60 to move up and down, as shown in fig. 1, when the coil 80 is not electrified, the first opening 51 of the control sleeve 50 is communicated with the first channel 13, so that the second cavity 12 is communicated with the first cavity 11, and oil cannot enter the first cavity 11; as shown in fig. 2, when the coil 80 is energized, the control sleeve 50 and the armature 60 move up synchronously, so that the first passage 13 is blocked by the control sleeve 50, and at the same time, the second opening 51 communicates with the second passage 17, so that the second cavity 12 communicates with the oil tank through the second passage 17, so that the inlet T21 communicates with the oil tank, and as the flow rate of the oil entering the first cavity 11 from the inlet T21 increases, a pressure drop occurs before and after the second through hole 31, so that a pressure difference occurs up and down the valve core 30, and the pressure difference enables the valve core 30 to slide against the elastic force of the first elastic member 40, so that the inlet T21 communicates with the outlet P22.
Preferably, the hydraulic motor protection device 100 for a construction machine further includes: the hydraulic control valve comprises an adjusting rod 91, a spring seat 92, a second elastic piece 93 and a pilot valve core 94. The adjusting rod 91 penetrates through the flux sleeve 70 and the armature 60 and extends into the second cavity 12; the spring seat 92 is arranged at the end of the adjusting rod 91; the upper end of the second elastic member 93 abuts against the spring seat 92; the pilot valve core 94 is fixedly disposed at the lower end of the second elastic member 93, and the pilot valve core 94 abuts against the first through hole 14 and can close the first through hole 14.
Preferably, the adjusting rod 91 is in threaded connection with the flux sleeve 70, and the adjusting rod 91 can be moved up and down by rotating the adjusting rod 91, so as to adjust and control the elastic force of the second elastic member 93 on the pilot valve core 94.
Preferably, the pilot poppet 94 is tapered, and a tip portion thereof is inserted into the first through hole 14 to close the first through hole 14.
Preferably, a first annular groove 15 is formed in the valve body 10, and the first annular groove 15 is communicated with the first through groove.
Preferably, a second annular groove 16 is provided on the valve body 10, and the second annular groove 16 is communicated with the second through groove.
It will be appreciated that by providing the first annular groove 15 and the second annular groove 16, the connection of the second volume 12 to the passage can also be achieved by communication with the annular grooves when the opening 51 is deflected.
Preferably, two openings 51 are provided in the control sleeve 50, and the two openings 51 are located on the same plane and can be simultaneously communicated with the first annular groove 15 or the second annular groove 16. A
It will be appreciated that the two openings 51 are oppositely disposed, adjacent to the first and second passages 13, 17 respectively, to allow oil to pass more smoothly from the second chamber 12 into the passages.
Preferably, a third elastic member 61 is disposed between the armature 60 and the flux sleeve 70.
It will be appreciated that by providing the third resilient member 61, the armature 60 can automatically push the control sleeve 50 to move downward after the coil 80 is de-energized, so that the second cavity 12 is communicated with the first passage 13.
Preferably, the armature 60 is provided with a first inclined surface 62 at the upper end, the flux sleeve 70 is provided with a second inclined surface 71 at the lower end, and the first inclined surface 62 is matched with the second inclined surface 71.
The working mode of the invention is as follows: the inlet T21 communicates with the hydraulic motor inlet, and the outlet P22 and the second passage 17 communicate with the oil tank.
When the coil 80 is not charged, as shown in fig. 1, under the action of the third elastic member 61, the armature 60 is located at the lower end position, and the control sleeve 50 is also located at the lower end position, at this time, the first cavity 11 is communicated with the second cavity 12 through the first passage 13, so that resultant force applied to the pilot valve element 94 is downward acting force of the second elastic member 93, and will be always in a closed state, pressures at the upper end and the lower end of the valve element 30 are equal, under the action of the first elastic member 40, the valve element 30 closes the outlet P22, no matter how large the pressure of the inlet T21 is, the inlet T21 and the outlet P22 are both in a cut-off state, all oil at the outlet P22 of the hydraulic pump will enter the hydraulic motor, and the hydraulic motor protection device 100 for engineering machinery will not shunt the flow rate at the inlet of the hydraulic motor, so that the hydraulic.
When the coil 80 is charged, as shown in fig. 2, under the action of the magnetic field generated by the coil 80, the armature 60 overcomes the acting force of the third elastic member 61 to drive the control sleeve 50 to move upward, so that the second cavity 12 is communicated with the oil tank through the second passage 17, and the first passage 13 is blocked by the control sleeve 50, at this time, the pilot valve core 94 receives the downward acting force of the second elastic member 93 and the upward thrust of the oil in the first cavity 11 to the pilot valve core 94, when the thrust of the oil to the pilot valve core 94 is greater than the elastic force of the second elastic member 93 to the pilot valve core 94, the pilot valve core 94 moves upward, the first through hole 14 is opened, the oil at the inlet T21 flows into the oil tank through the second through hole 31, the first cavity 11, the first through hole 14, the second cavity 12, and the second through hole 17 in sequence, and due to the blocking effect of the second through hole 31, a differential pressure is generated at the upper and lower ends, the valve core 30 moves upwards under the action of the oil until the inlet T21 is communicated with the outlet P22, and the oil directly enters the oil tank from the hydraulic motor pipeline, so that the pressure at the inlet of the hydraulic motor is prevented from continuously rising, and the protection function of the hydraulic motor is realized. When the pressure of the oil to the pilot valve core 94 is smaller than the set pressure of the second elastic member 93 to the pilot valve core 94, the pilot valve core 94 closes the first through hole 14, so that the pressure difference between the upper end and the lower end of the valve core 30 disappears, and the valve core 30 descends under the action of the first elastic member 40 to block the inlet T21 and the outlet P22. Further, the amount of compression of the spring can be adjusted by rotating the adjustment lever 91 to adjust the set pressure level, and for example, by rotating the adjustment lever 91 to move the adjustment lever 91 downward, the amount of compression of the second elastic member 93 increases, the pre-pressure on the pilot valve core 94 increases, and the lower limit of the pressure to be released can be increased.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. 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. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A hydraulic motor protection device for construction machinery is characterized by comprising:
the valve body is provided with a first containing cavity and a second containing cavity, the first containing cavity is communicated with the second containing cavity through a first channel and a first through hole, and the second containing cavity is communicated with the oil tank through a second channel;
the valve sleeve is cylindrical and is fixedly arranged at the first cavity of the valve body; the valve body is provided with an inlet T and an outlet P, the inlet T is communicated with a hydraulic motor, the outlet P is positioned on the side surface of the valve body and is communicated with an oil tank,
the valve core is arranged in the valve sleeve in a sliding mode and provided with a through second through hole, the second through hole is communicated with the inlet T and the first cavity, and the valve core can block the inlet T and the outlet P;
the first elastic piece is arranged between the valve core and the valve body, so that the valve core is abutted to the valve sleeve;
the control sleeve is located in the second containing cavity and is connected to the valve body in a sliding mode, an opening is formed in the control sleeve, the control sleeve is provided with a first working position and a second working position, when the control sleeve is located at the first working position, the opening is communicated with the first channel, and when the control sleeve is located at the second working position, the opening is communicated with the second channel.
2. The hydraulic motor protection device for construction machinery according to claim 1, further comprising:
the magnetic conduction sleeve is fixedly connected to the upper end of the valve body;
the armature is arranged in the magnetic conduction sleeve in a sliding mode and is fixedly connected with the control sleeve;
a coil which is sleeved outside the magnetic conduction sleeve and can control the armature to move up and down,
when the coil is not electrified, the first opening of the control sleeve is communicated with the first channel, so that the second cavity is communicated with the first cavity, and oil cannot enter the first cavity; when the coil is electrified, the control sleeve and the armature move upwards synchronously, so that the first channel is cut off by the control sleeve, meanwhile, the second opening is communicated with the second channel, the second cavity is communicated with the oil tank through the second channel, the inlet T is communicated with the oil tank, along with the increase of the flow velocity of oil entering the first cavity from the inlet T, the oil can enable the valve core to overcome the elasticity of the first elastic piece to slide, and the inlet T is communicated with the outlet P.
3. The hydraulic motor protection device for construction machinery according to claim 2, further comprising:
the adjusting rod penetrates through the magnetic sleeve and the armature and extends into the second containing cavity;
the spring seat is arranged at the end part of the adjusting rod;
the upper end of the second elastic piece is abutted with the spring seat;
the pilot valve core is fixedly arranged at the lower end of the second elastic part and is abutted against the first through hole, so that the first through hole can be closed.
4. The hydraulic motor protection device for construction machinery according to claim 3, wherein the adjustment lever is screwed to the flux sleeve, and the adjustment lever can be moved up and down by rotating the adjustment lever, thereby adjusting the elastic force of the second elastic member against the pilot valve body.
5. The hydraulic motor protection device for construction machinery according to claim 3, wherein the pilot spool is tapered, and a tip portion thereof is inserted into the first through hole to close the first through hole.
6. The hydraulic motor protection device for construction machinery according to claim 1, wherein a first annular groove is provided in the valve body, and the first annular groove communicates with the first through groove.
7. The hydraulic motor protection device for construction machinery according to claim 6, wherein a second annular groove is provided in the valve body, and the second annular groove communicates with the second through groove.
8. The hydraulic motor protector for construction machinery as claimed in claim 7, wherein the control sleeve is provided with two openings, and the two openings are located on the same plane and can be communicated with the first annular groove or the second annular groove at the same time.
9. The hydraulic motor protection device for construction machinery according to claim 2, wherein a third elastic member is provided between the armature and the flux sleeve.
10. The hydraulic motor protection device for construction machinery according to claim 2, wherein a first inclined surface is provided at an upper end of the armature, a second inclined surface is provided at a lower end of the flux sleeve, and the first inclined surface is engaged with the second inclined surface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010548053.2A CN111720380A (en) | 2020-06-16 | 2020-06-16 | Hydraulic motor protection device for engineering machinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010548053.2A CN111720380A (en) | 2020-06-16 | 2020-06-16 | Hydraulic motor protection device for engineering machinery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111720380A true CN111720380A (en) | 2020-09-29 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010548053.2A Withdrawn CN111720380A (en) | 2020-06-16 | 2020-06-16 | Hydraulic motor protection device for engineering machinery |
Country Status (1)
| Country | Link |
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| CN (1) | CN111720380A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111660439A (en) * | 2020-06-16 | 2020-09-15 | 邵立坤 | Motor control device for concrete mixer truck |
-
2020
- 2020-06-16 CN CN202010548053.2A patent/CN111720380A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111660439A (en) * | 2020-06-16 | 2020-09-15 | 邵立坤 | Motor control device for concrete mixer truck |
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Application publication date: 20200929 |