Resistance type liquid level switch

Abstract

The utility model relates to a resistance type liquid level switch which comprises a probe shell and a probe connected to the lower end of the probe shell, and the probe comprises a fixing and sealing block fixedly connected to the lower end of the probe shell, an anode stainless steel rod and a cathode stainless steel rod, the lower end of the positive stainless steel rod and the lower end of the negative stainless steel rod are arranged in parallel, the upper end of the positive stainless steel rod and the upper end of the negative stainless steel rod are both connected with a connecting cable penetrating into the probe shell, the probe shell penetrates through the connecting flange, and threaded connection is achieved at the penetrating position. According to the utility model, through detecting the resistance between the probes, the liquid level switch can accurately distinguish the two conditions that the liquid level switch is contacted with conductive liquid and leaves the liquid based on the huge difference between the conductive liquid resistance and the air resistance; the situation that a mechanical liquid level switch such as a floating ball liquid level switch moves up and down along with the liquid level in the moving process, and frequent action or misoperation is generated can be effectively prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of liquid level switches, in particular to a resistance type liquid level switch. Background Art

[0002] At present, a simple mechanical liquid level float switch is usually used in a closed container. It does not have a self-checking function, so it needs to be checked and maintained regularly. At the same time, the float is greatly affected by the viscosity and density of the liquid itself, and the measurement accuracy is poor. It may also cause frequent actions or false actions due to the movement of the liquid surface in the container. Utility Model Content

[0003] The utility model aims at the deficiencies of the prior art and provides a resistive liquid level switch, which can effectively prevent mechanical liquid level switches such as float liquid level switches from frequently operating or malfunctioning due to the up and down movement of the liquid surface during movement.

[0004] The utility model is realized through the following technical scheme, providing a resistive liquid level switch, including a probe housing and a probe connected to the lower end of the probe housing, the probe including a sealing block fixedly connected to the lower end of the probe housing and a positive stainless steel rod and a negative stainless steel rod both vertically passing through the sealing block, the lower end of the positive stainless steel rod and the lower end of the negative stainless steel rod are arranged in parallel, the upper end of the positive stainless steel rod and the upper end of the negative stainless steel rod are both connected to a connecting cable that penetrates into the probe housing, and also includes a connecting flange, the probe housing passes through the connecting flange and is threadedly connected at the passing point.

[0005] This solution detects the resistance between the probes. Based on the huge difference between the resistance of the conductive liquid and the resistance of the air, the liquid level switch can accurately distinguish between the two situations of contacting with the conductive liquid and leaving the liquid, thereby realizing the function of the liquid level switch.

[0006] As an optimization, the upper end of the probe housing is bolted with a probe end cover. By disassembling the probe end cover, operations such as wiring of cables inside the probe housing can be achieved.

[0007] As an optimization, the sealing block passes through the lower end of the probe housing and is threadedly connected. In this solution, the sealing block can be screwed down to replace the probe.

[0008] As an optimization, the outer ring of the sealing block is fixed with an annular protrusion, and a sealing gasket is installed between the annular protrusion and the probe housing. In this solution, the sealing gasket is pressed under the probe housing by the protrusion, thereby achieving sealing here and preventing water from entering the probe housing.

[0009] As an optimization, it also includes a transmitter housing, and one end of the connecting cable away from the probe housing penetrates into the transmitter housing. The transmitter housing in this solution is used to install the liquid level switch mainboard.

[0010] As an optimization, a transmitter end cover is bolted to the transmitter housing. The transmitter end cover in this solution can be removed, thereby facilitating the disassembly and assembly of the internal liquid level switch mainboard.

[0011] As an optimization, the connecting cable is provided with a cable connector located at the side of the probe housing. The connection of the connecting cable at the side of the probe housing is achieved through the cable connector.

[0012] The beneficial effects of the utility model are:

[0013] 1. The liquid level in the closed container moves up and down or tilts, etc., and has no effect on it;

[0014] 2. Not affected by the physical properties of the liquid level itself (such as viscosity and density);

[0015] 3. Not affected by the high and low temperature of the liquid being tested, and not affected by high temperature demagnetization;

[0016] 4. It can display the current real-time liquid level and output level signal to indicate the liquid level, so as to judge whether the closed container should be replenished with solution.

[0017] 5. The split design separates the probe part, reduces the installation volume, and is suitable for narrow installation places. The probe does not contain a control circuit, has high reliability, does not require maintenance during use, and the transmitter part can be appropriately arranged in a convenient operating position.

[0018] 6. The probe is made of stainless steel, and the detection signal is low-voltage alternating current, which will not produce liquid electrolysis reaction and requires no maintenance for long-term use. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the utility model;

[0020] Figure 2 This is a front view of the utility model;

[0021] Figure 3 It is the left view of the utility model;

[0022] Figure 4 For this utility model Figure 2 Sectional view of the middle AA plane;

[0023] Figure 5 For this utility model Figure 3 Middle BB plane section view;

[0024] Figure 6 For this utility model Figure 3 Middle CC section view;

[0025] As shown in the figure:

[0026] 1. Probe, 11. Sealing block, 12. Positive stainless steel rod, 13. Negative stainless steel rod, 2. Probe housing, 3. Probe end cover, 4. Connecting flange, 5. Sealing gasket, 6. Connecting cable, 7. Transmitter housing, 8. Transmitter end cover, 9. Liquid level switch mainboard. DETAILED DESCRIPTION

[0027] In order to clearly illustrate the technical features of this solution, this solution is described below through a specific implementation method.

[0028] like Figures 1 to 6 As shown, a resistive liquid level switch of the present invention comprises a probe housing 2, a transmitter housing 7 and a probe 1 connected to the lower end of the probe housing 2. The probe housing 2 is installed above the liquid tank to be detected, and the transmitter housing 7 can be installed at any suitable position.

[0029] like Figure 4 As shown, the probe 1 includes a sealing block 11 fixedly connected to the lower end of the probe housing 2 and a positive stainless steel rod 11 and a negative stainless steel rod 13 both vertically passing through the sealing block 11. The sealing block 11 is made of insulating material to fix the positive stainless steel rod 11 and the negative stainless steel rod 13. The lower end of the positive stainless steel rod 11 and the lower end of the negative stainless steel rod 13 are arranged in parallel, and the lower ends are inserted into the liquid. When in use, the resistance value between the positive stainless steel rod 11 and the negative stainless steel rod 13 is detected.

[0030] The connecting cable 6 is connected between the probe housing 2 and the transmitter housing 7. The upper ends of the positive stainless steel rod 11 and the negative stainless steel rod 13 are both connected to the connecting cable 6 that penetrates the probe housing 2. In this embodiment, the connecting cable 6 is equipped with a cable connector located on the side of the probe housing 2. The cable connector realizes the connection of the connecting cable 6 parts on both sides of the probe housing 2, which is convenient for disassembly and assembly.

[0031] The upper end of the sealing block 11 is cylindrical and has an external thread, and the sealing block 11 passes through the lower end of the probe housing 2 and is threadedly connected thereto, thereby extending the upper ends of the positive stainless steel rod 11 and the negative stainless steel rod 13 into the interior of the probe housing 2 .

[0032] In order to improve the sealing effect, an annular protrusion is fixedly connected to the outer ring of the sealing block 11 . The annular protrusion is below the probe housing 2 . A sealing gasket 5 is installed between the annular protrusion and the probe housing 2 .

[0033] The upper end of the probe housing 2 is bolted with a probe end cover 3. The probe end cover 3 seals the upper end opening of the probe housing 2, and a sealing ring is installed between the upper end of the probe housing 2 and the probe end cover 3.

[0034] It also includes a connecting flange 4, which is connected to the upper end of the liquid tank by multiple circumferential bolts. A sealing ring is installed between the connecting flange 4 and the liquid tank. The probe housing 2 passes through the connecting flange 4 and is threadedly connected at the passing point. The outer ring of the probe housing 2 is stepped, the small diameter end passes through the connecting flange 4, and the lower end face of the large diameter end fits on the connecting flange 4.

[0035] A liquid level switch mainboard 9 is installed in the transmitter housing 7 for receiving resistance value signals. The end of the connecting cable 6 away from the probe housing 2 penetrates the transmitter housing 7 to be connected to the liquid level switch mainboard 9. A transmitter end cover 8 is bolted to the transmitter housing 7.

[0036] The use of the utility model:

[0037] The positive stainless steel rod 11 and the negative stainless steel rod 13 are inserted into the liquid surface. By detecting the resistance between the probes, based on the huge difference between the resistance of the conductive liquid and the resistance of the air, the liquid level switch can accurately distinguish between the two situations of contacting with the conductive liquid and leaving the liquid, thereby realizing the function of the liquid level switch. The resistance signal is transmitted to the liquid level switch mainboard 9 in the transmitter housing 7, thereby realizing the liquid level switch function. At the same time, the current liquid level can be displayed.

[0038] Of course, the above description is not limited to the above examples. The technical features not described in the present invention can be achieved by or by adopting the existing technology, which will not be repeated here. The above embodiments and drawings are only used to illustrate the technical scheme of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that the changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not deviate from the purpose of the present invention and should also fall within the scope of protection of the claims of the present invention.

Claims

1. A resistive liquid level switch, characterized in that: The invention comprises a probe housing (2) and a probe (1) connected to the lower end of the probe housing (2), wherein the probe (1) comprises a sealing block (11) fixed to the lower end of the probe housing (2) and a positive stainless steel rod (12) and a negative stainless steel rod (13) both vertically passing through the sealing block (11), wherein the lower end of the positive stainless steel rod (12) and the lower end of the negative stainless steel rod (13) are arranged in parallel, and the upper end of the positive stainless steel rod (12) and the upper end of the negative stainless steel rod (13) are both connected to a connection cable (6) that penetrates into the probe housing (2), and further comprises a connecting flange (4), wherein the probe housing (2) passes through the connecting flange (4) and is threadedly connected at the passing position.

2. A resistive liquid level switch according to claim 1, characterized in that: The upper end of the probe housing (2) is bolted to a probe end cover (3).

3. A resistive liquid level switch according to claim 1, characterized in that: The sealing block (11) passes through the lower end of the probe housing (2) and is threadedly connected therethrough.

4. A resistive liquid level switch according to claim 1, characterized in that: An annular protrusion is fixedly connected to the outer ring of the sealing block (11), and a sealing gasket (5) is installed between the annular protrusion and the probe housing (2).

5. The resistive liquid level switch according to claim 1, characterized in that: It also comprises a transmitter housing (7), and one end of the connecting cable (6) away from the probe housing (2) penetrates into the transmitter housing (7).

6. A resistive liquid level switch according to claim 5, characterized in that: The transmitter housing (7) is bolted with a transmitter end cover (8).

7. A resistive liquid level switch according to claim 1, characterized in that: The connecting cable (6) is provided with a cable connector located on the side of the probe housing (2).

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