Magnetic floater liquid level switch
By using magneto float level switches in industrial sites and using the combination of magnetic field force and non-magnetic materials, the problems of low control accuracy, large space, and susceptible to water flow traction of traditional cable float level switches are solved, achieving high Accurate, small space and reliable liquid level control.
Patent Information
- Application Number
- CN202311013768.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-14
- Publication Date
- 2025-02-21
AI Technical Summary
The existing cable float level switches have problems in industrial sites such as low control accuracy, large space occupancy, susceptible to water flow, easy to entangle with cables, and poor sealing, resulting in inability to work normally.
Using magnet float level switch, hollow cylindrical magnet float made of permanent magnet material cooperates with the inner sleeve and outer sleeve made of non-magnetic material, and realizes liquid level detection and switch control through magnetic field force and structural design to avoid Cable tangle and sealing issues.
It realizes the liquid level switch function with high control accuracy, small space, no traction by water flow, difficult cables to wrap around, tight seals and simple maintenance, and replaces the traditional cable-type float level switch.
Smart Images
Figure CN119495530A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of float liquid level switches, and in particular relates to a magnetic float liquid level switch. Background Art
[0002] The automatic level control of industrial on-site storage pits or water tanks is mostly composed of a cable-type float level switch and a water pump. The float is placed at different depths in the pit or water tank according to different liquid level alarm settings. When the liquid level rises to the high alarm threshold, the high alarm float level switch is triggered, and the interlocking water pump automatically starts to drain water; when the water level drops to the low alarm threshold, the low alarm float level switch is triggered, and the interlocking water pump automatically stops, thereby realizing automatic control of the liquid level in the pit or water tank and the liquid level alarm.
[0003] Although cable float level switches are widely used in industrial sites, they also have the following problems:
[0004] 1) The working characteristics of the float level switch result in low control accuracy and the set value cannot be accurately set according to production needs.
[0005] 2) If the water storage pit or water tank space is small, and the distance between the water pump and the float level switch is close, when the pump is started, the float level switch is easily pulled by the water flow and cannot float up and trigger.
[0006] 3) In order to drain water quickly, two sets of pumps and multiple float level switches are generally set up on site to cooperate with each other.
[0007] The cables of the float level switch are easily entangled with each other under the action of water flow, resulting in failure to work properly.
[0008] 4) If the float level switch is immersed in water for a long time, if cracks appear on the float part or the contact part between the float and the cable is not sealed tightly, water will enter the float, and the float level switch will not be able to float up and trigger, and the insulation of the level switch will also be reduced. Summary of the invention
[0009] The purpose of the present invention is to provide a magnetic float liquid level switch, which has the characteristics of high control accuracy, small working space, and will not fail to work normally due to cable entanglement and poor sealing, and can replace the cable float liquid level switch widely used in industrial production.
[0010] In order to achieve the above object, the technical solution adopted by the present invention is:
[0011] A magnetic float liquid level switch, wherein a proximity switch body is fixed at the bottom end of an inner sleeve, one end of a proximity switch cable is connected to the proximity switch body, and the other end is connected to an aviation plug, an inner sleeve cover plate is installed at the upper end of the inner sleeve, a mounting back plate is fixed to the inner sleeve cover plate, an aviation plug is fixed to the mounting back plate, the inner sleeve is connected to an outer sleeve, a magnetic float is placed in the outer sleeve, and can float up and down with the liquid level in the outer sleeve, and a filter is installed at the bottom of the outer sleeve.
[0012] The inner sleeve is a cylindrical tube with a closed bottom end.
[0013] The other end of the proximity switch cable is connected to the aviation plug by welding.
[0014] The mounting back plate is fixed to the inner sleeve cover plate by four mounting back plate fixing bolts.
[0015] The inner sleeve is connected to the outer sleeve by three symmetrically distributed inner sleeve fixing bolts.
[0016] A knob is provided on the inner sleeve fixing bolt, and the inner sleeve fixing bolt can be rotated by the knob to adjust the relative position of the inner sleeve and the outer sleeve.
[0017] The magnetic float is a hollow cylinder made of permanent magnet material.
[0018] Working principle of the magnetic float liquid level switch: After the magnetic float liquid level switch is installed in the pit or water tank, water enters the outer sleeve after filtering out impurities through the filter, and the magnetic float moves up and down with the change of liquid level; when the liquid level in the pit or water tank rises to a certain height, the magnetic float rises with the liquid level and reaches a certain distance from the inner sleeve, the magnetic field force of the proximity switch body is strengthened, and the micro switch inside the limit is closed; when the liquid level in the pit or water tank drops to a certain height, the magnetic float drops with the liquid level and reaches a certain distance from the inner sleeve, the magnetic field force of the proximity switch body is weakened, and the micro switch inside the limit is disconnected.
[0019] Assuming that the length of the outer sleeve is Y, the length of the inner sleeve is Z, the length of the inner sleeve exposed from the outer sleeve is X, and when the distance between the magnetic float and the inner sleeve is L, the proximity switch body is triggered by the magnetic field force of the magnetic float. By calculation, the fixed value of the magnetic float liquid level switch can be obtained as:
[0020] Fixed value = (X + Y) - (Z + L)
[0021] Since the outer sleeve length Y, the inner sleeve length Z, and the distance L between the magnetic float and the inner sleeve when the limit switch is triggered are known, the set value of the magnetic float liquid level switch depends on the length X of the inner sleeve exposed from the outer sleeve. The three inner sleeve fixing bolts can be turned by the knob to adjust the length X of the inner sleeve exposed from the outer sleeve, thereby changing the set value of the magnetic float liquid level switch.
[0022] Force analysis of magnetic float: Assume that the gravity of the magnetic float is G and its buoyancy in water is F n The magnetic force of the micro switch inside the proximity switch body is F m , then the force on the magnetic float always satisfies:
[0023] G=F n +F m
[0024] Since the gravity G of the magnetic float is much greater than the magnetic force F between the micro switch inside the proximity switch body and the magnetic float m Therefore, when the magnetic float is close enough to the inner sleeve, the magnetic float will not be adsorbed to the bottom of the inner sleeve due to magnetic force and cannot work normally.
[0025] The beneficial effects achieved by the present invention are:
[0026] 1. The device has high control accuracy and can quickly and accurately set the liquid level switch setting value by adjusting the position of the inner sleeve.
[0027] 2. The device requires little space to work. In a narrow pit or water tank, even if it is close to the water pump, it will not affect the function of the magnetic float liquid level switch.
[0028] 3. The device will not affect the function of the magnetic float liquid level switch due to the cables being entangled with each other.
[0029] 4. The limit switch of the device is separated from the magnetic float, and the magnetic float can be completely sealed, so there is no water ingress that causes it to be unable to float; the limit switch is completely separated from the water by the inner sleeve, which can ensure that the insulation of the limit switch meets the requirements.
[0030] 5. The device has a simple structure and low maintenance cost. If the magnetic float level switch fails, the internal limit switch can be directly replaced without replacing the entire device. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] Figure 1 This is a front view of a magnetic float liquid level switch;
[0032] Figure 2 A top view of a magnetic float liquid level switch;
[0033] Figure 3 The bottom diagram of the outer sleeve;
[0034] In the figure: 1 is the outer sleeve; 2 is the inner sleeve; 3 is the inner sleeve fixing bolt; 4 is the aviation plug; 5 is the mounting back plate; 6 is the mounting back plate fixing bolt; 7 is the inner sleeve cover plate; 8 is the proximity switch cable; 9 is the proximity switch body; 10 is the magnetic float; 11 is the filter screen. DETAILED DESCRIPTION
[0035] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.
[0036] A magnetic float liquid level switch includes: an outer sleeve 1, an inner sleeve 2, an inner sleeve fixing bolt 3, an aviation plug 4; a mounting back plate 5, a mounting back plate fixing bolt 6, an inner sleeve cover plate 7, a proximity switch cable 8, a proximity switch body 9, a magnetic float 10, and a filter screen 11. The magnetic float 10 is a hollow cylinder made of a permanent magnet material and can float on the water surface. In order to avoid affecting the operation of the magnetic float 10, all of the above devices are made of non-magnetic materials except for the micro switch in the proximity switch body 9.
[0037] Working principle of magnetic float level switch:
[0038] After the magnetic float liquid level switch is installed in the pit or water tank, water passes through the filter 11 to filter out impurities and then enters the outer sleeve 1, and the magnetic float 10 moves up and down as the liquid level changes. When the liquid level in the pit or water tank rises to a certain height, the magnetic float 10 floats up with the liquid level and reaches a certain distance from the inner sleeve 2, the magnetic field force of the proximity switch body 9 becomes stronger due to the magnetic float 10, and the micro switch inside the limit is closed; when the liquid level in the pit or water tank drops to a certain height, the magnetic float 10 drops with the liquid level and reaches a certain distance from the inner sleeve 2, the magnetic field force of the proximity switch body 9 becomes weaker due to the magnetic float 10, and the micro switch inside the limit is disconnected.
[0039] Assume that the length of the outer sleeve 1 is Y, the length of the inner sleeve 2 is Z, and the length of the inner sleeve 2 exposed from the outer sleeve 1 is X. When the distance between the magnetic float 10 and the inner sleeve 2 is L, the proximity switch body 9 is triggered by the magnetic field force of the magnetic float 10. By calculation, the fixed value of the magnetic float liquid level switch can be obtained as:
[0040] Fixed value = (X + Y) - (Z + L)
[0041] Since the length of the outer sleeve 1 is Y, the length of the inner sleeve 2 is Z, and the distance L between the magnetic float 10 and the inner sleeve 2 when the limit switch is triggered is known, the fixed value of the magnetic float liquid level switch depends on the length X of the inner sleeve 2 exposed from the outer sleeve 1. The three inner sleeve fixing bolts 3 can be turned by the knob to adjust the length X of the inner sleeve 2 exposed from the outer sleeve 1, thereby changing the fixed value of the magnetic float liquid level switch.
[0042] Force analysis of magnetic float:
[0043] Assume that the gravity of the magnetic float 10 is G and its buoyancy in water is F n , the magnetic force of the micro switch inside the proximity switch body 9 is F m , then the force on the magnetic float 10 always satisfies:
[0044] G=F n +F m
[0045] Since the gravity G of the magnetic float 10 is much greater than the magnetic force F between the micro switch inside the proximity switch body 9 and the magnetic float 10 m Therefore, when the distance between the magnetic float 10 and the inner sleeve 2 is close enough, the magnetic float 10 will not be adsorbed to the bottom end of the inner sleeve 2 due to magnetic force and cannot work normally.
[0046] The inner sleeve 2 is a cylindrical cylinder with a closed bottom, and the proximity switch body 9 is fixed at the bottom of the inner sleeve 2. One end of the proximity switch cable 8 is connected to the proximity switch body 9, and the other end is connected to the aviation plug 4 by welding. The inner sleeve cover plate 7 is installed on the upper end of the inner sleeve 2 to prevent impurities from entering the inner sleeve. The mounting back plate 5 is fixed on the inner sleeve cover plate 7 by 4 mounting back plate fixing bolts 6, and the aviation plug 4 is fixed on the mounting back plate 5. The inner sleeve 2 is connected to the outer sleeve 1 by 3 symmetrically distributed inner sleeve fixing bolts 3. There is a knob on the inner sleeve fixing bolt 3, and the inner sleeve fixing bolt 3 can be rotated by the knob to adjust the relative position of the inner sleeve 2 and the outer sleeve 1. The magnetic float 10 is placed in the outer sleeve 1 and can float up and down with the liquid level in the outer sleeve 1. In order to prevent the magnetic float 10 from falling out of the outer sleeve 1 and impurities from entering the outer sleeve 1, a filter screen 11 is installed at the bottom of the outer sleeve 1.
Claims
1. A magnetic float liquid level switch, characterized in that: The proximity switch body is fixed at the bottom end of the inner sleeve, one end of the proximity switch cable is connected to the proximity switch body, and the other end is connected to the aviation plug. The inner sleeve cover is installed on the upper end of the inner sleeve, the mounting back plate is fixed on the inner sleeve cover, the aviation plug is fixed on the mounting back plate, the inner sleeve is connected to the outer sleeve, the magnetic float is placed in the outer sleeve, and can float up and down with the liquid level in the outer sleeve, and a filter is installed at the bottom of the outer sleeve.
2. The magnetic float liquid level switch according to claim 1, characterized in that: The inner sleeve is a cylindrical tube with a closed bottom end.
3. The magnetic float liquid level switch according to claim 1, characterized in that: The other end of the proximity switch cable is connected to the aviation plug by welding.
4. The magnetic float liquid level switch according to claim 1, characterized in that: The mounting back plate is fixed to the inner sleeve cover plate by four mounting back plate fixing bolts.
5. The magnetic float liquid level switch according to claim 1, characterized in that: The inner sleeve is connected to the outer sleeve by three symmetrically distributed inner sleeve fixing bolts.
6. The magnetic float liquid level switch according to claim 5, characterized in that: A knob is provided on the inner sleeve fixing bolt, and the inner sleeve fixing bolt can be rotated by the knob to adjust the relative position of the inner sleeve and the outer sleeve.
7. The magnetic float liquid level switch according to claim 1, characterized in that: The magnetic float is a hollow cylinder made of permanent magnet material.
8. The magnetic float liquid level switch according to claim 1, characterized in that: Working principle of the magnetic float liquid level switch: After the magnetic float liquid level switch is installed in the pit or water tank, water enters the outer sleeve after filtering out impurities through the filter, and the magnetic float moves up and down with the change of liquid level; when the liquid level in the pit or water tank rises to a certain height, the magnetic float rises with the liquid level and reaches a certain distance from the inner sleeve, the magnetic field force of the proximity switch body is strengthened, and the micro switch inside the limit is closed; when the liquid level in the pit or water tank drops to a certain height, the magnetic float drops with the liquid level and reaches a certain distance from the inner sleeve, the magnetic field force of the proximity switch body is weakened, and the micro switch inside the limit is disconnected.
9. The magnetic float liquid level switch according to claim 5, characterized in that: Assuming that the length of the outer sleeve is Y, the length of the inner sleeve is Z, the length of the inner sleeve exposed from the outer sleeve is X, and when the distance between the magnetic float and the inner sleeve is L, the proximity switch body is triggered by the magnetic field force of the magnetic float. By calculation, the fixed value of the magnetic float liquid level switch can be obtained as: Fixed value = (X + Y) - (Z + L) Since the outer sleeve length Y, the inner sleeve length Z, and the distance L between the magnetic float and the inner sleeve when the limit switch is triggered are known, the set value of the magnetic float liquid level switch depends on the length X of the inner sleeve exposed from the outer sleeve. The three inner sleeve fixing bolts can be turned by the knob to adjust the length X of the inner sleeve exposed from the outer sleeve, thereby changing the set value of the magnetic float liquid level switch.
10. The magnetic float liquid level switch according to claim 1, characterized in that: Force analysis of magnetic float: Assume that the gravity of the magnetic float is G and its buoyancy in water is F n The magnetic force of the micro switch inside the proximity switch body is F m , then the force on the magnetic float always satisfies: G=F n +F m Since the gravity G of the magnetic float is much greater than the magnetic force F between the micro switch inside the proximity switch body and the magnetic float m Therefore, when the magnetic float is close enough to the inner sleeve, the magnetic float will not be adsorbed to the bottom of the inner sleeve due to magnetic force and cannot work normally.