Sacrificial anode structure for high-insulation water heater
Technical Field
The invention belongs to the technical field of parts of water heaters, and particularly relates to a sacrificial anode structure for a high-insulation water heater.
Background
One or more sacrificial anode rods are generally required to be installed in the existing water storage type water heater to protect a water storage inner container in a long-term service process and prevent corrosion and water leakage. The sacrificial anode needs to be connected with the liner and ensure good electrical conduction. The galvanic cell is formed in the environment of domestic water due to the potential difference between the two, and the protection of the inner container is realized through the self-sacrifice of the anode bar. Therefore, the anode rod is a consumable product, has a certain service life and needs to be replaced regularly. In order to detect the consumption condition of the anode bar in real time and remind a user of replacement in time, a novel intelligent sacrificial anode-signal anode appears in the market. Unlike conventional sacrificial anodes, the sacrificial anode needs to be insulated and connected with the inner container first and then connected with the inner container through a lead. The existing insulation connection structure is generally composed of a sacrificial anode rod 1, an insulation sealing gasket 2, a screw head 3 and a sealing gasket 4 (shown in figure 1). Under the specific use condition, the screw head 3 is connected with the inner container, and the sacrificial anode rod 1 is communicated with the inner container through a lead. However, in such a structure, when the insulating mat 4 is pressed against the screw head 3, a part of the air gap 8 is easily formed between the insulating mat 4 and the insulating mat seal 2. The air gap is short and the left and right ends are not separated by an insulator. By using the finite element electric field analysis, it is found that the air gap can cause the insulation of the device to be reduced under the finite element electric field analysis. Electric field analysis shows that after an air gap is generated under 1000v voltage, the field intensity of the edge surfaces of the insulating sealing gasket 2 and the insulating gasket 4 reaches 0.7kV/mm, and if the field intensity of the air edge surfaces exceeds 0.4 kV/mm, under the conditions of humidity, dirt and the like, an edge surface discharge channel can be generated, so that the resistance is reduced, and the insulativity is reduced. Under high voltage, especially under the condition that air humidity is big, dirty, can follow the surface formation intermittent type nature discharge channel of insulating sealed pad 2, insulating pad 4, can lead to insulating resistance to reduce and form the electric leakage channel, lead to insulating properties to descend, cause the quality unstability in the production process, also can cause simultaneously to have the electric leakage in the use, bring the real-time detection data error of signal positive pole. Therefore, the problem of unstable insulation performance of the magnesium rod insulation protection device of the water heater is urgently solved.
Disclosure of Invention
The invention aims to provide a sacrificial anode structure for a high-insulation water heater, which consists of a sacrificial anode rod 1, an insulation sealing gasket 2, a screw head 3, an insulation gasket 4, a fastening nut 5 and a sacrificial anode rod thread 6, wherein the insulation sealing gasket 2, the screw head 3 and the insulation gasket 4 are sequentially sleeved on the sacrificial anode rod 1 through respective inner holes thereof, and all components are tightly pressed on the sacrificial anode rod 1 through the sacrificial anode rod thread 6 by the fastening nut 5 to form an integral structure; meanwhile, the lower end of the insulating gasket 4 is inserted into the stepped bulge 7 of the insulating gasket 2, so that the totally-enclosed isolated insulation between the sacrificial anode rod 1 and the screw head 3 is realized.
The lower end of the insulating gasket 4 is inserted into the stepped bulge 7 of the insulating gasket 2 and is in tight fit, and the outer diameter of the lower end of the insulating gasket is 0.2mm to 0.3mm larger than the inner diameter of the stepped bulge 7 of the insulating gasket 2.
The stepped bulge 7 of the insulating sealing gasket 2 is inserted into the lower end of the insulating gasket 4 and is in close fit with the lower end of the insulating gasket; the inner diameter of the lower end of the insulating gasket is 0.2mm to 0.3mm smaller than the outer diameter of the stepped bulge 7 of the insulating gasket 2.
The insulating gasket or the insulating sealing gasket is designed into an insulating sealing sleeve structure.
The insulating pad is made of nylon, polypropylene, polytetrafluoroethylene or epoxy resin in a rigid insulating material; the insulating sealing gasket is made of ethylene propylene diene monomer or silicon rubber in high-quality insulating rubber.
The sacrificial anode rod is made of magnesium alloy or aluminum alloy.
The invention has the beneficial effects that:
1. the insulating sealing gasket is designed into a step type, is provided with the raised additional ring, and forms circumferential surface interference overlapping with the insulating gasket when being butted with the insulating gasket. Because this structure does not have the place that insulating cover parcel can not arrive, has guaranteed insulating stability to a great extent.
2. The design process adopts an interference design, so that the contact surface between the lower end of the insulating gasket and the insulating gasket forms interference contact, pressure in the horizontal direction is generated, tight fit is formed between the lower end of the insulating gasket and the insulating gasket, and the air gap phenomenon in the vertical direction, which can be caused by too large gaps, is avoided. The problem of the insulating properties that arouses because machining precision, installation compactness descend by a wide margin is avoided.
3. The interference compresses tightly the design and protruding formula is isolated can effectively avoid external environment like humidity, quality of water, air etc. to insulating nature's of insulating apparatus influence.
Drawings
FIG. 1 is a schematic diagram of an original sacrificial anode with high insulation.
Fig. 2 is a schematic view of a magnesium rod sealing structure.
Fig. 3 is a schematic view of a magnesium rod sealing structure II.
Fig. 4 is a schematic view of the shape of the insulating mat or the insulating gasket designed as an insulating sealing sleeve.
Detailed Description
The invention provides a sacrificial anode structure for a high-insulation water heater, which is further described with reference to the attached drawings.
Fig. 2 and 3 are schematic diagrams showing the structure of the high-insulation sacrificial anode.
As shown in fig. 2, the sacrificial anode structure is composed of a sacrificial anode rod 1, an insulating sealing gasket 2, a screw head 3, an insulating gasket 4, a fastening nut 5 and a sacrificial anode rod thread 6, the insulating sealing gasket 2, the screw head 3 and the insulating gasket 4 are sequentially sleeved on the sacrificial anode rod 1 through respective inner holes thereof, and the fastening nut 5 tightly presses each component on the sacrificial anode rod 1 through the sacrificial anode rod thread 6 to form an integral structure; wherein the insulating sealing gasket 2 is designed into a structure with a step type bulge 7; in the installation state, the fastening nut 5 presses the insulating pad 4 on the screw head 3, and presses the screw head 3 on the upper surface of the insulating sealing pad 2 through force transmission to realize sealing; meanwhile, the lower end of the insulating gasket 4 is inserted into the stepped boss 7 of the insulating gasket 2 and is in close fit with the stepped boss. The outer diameter of the lower end of the insulating gasket 4 is 0.2mm to 0.3mm larger than the inner diameter of the stepped bulge 7 of the insulating gasket 2; and the totally-enclosed isolated insulation between the sacrificial anode rod 1 and the screw head 3 is realized.
As shown in fig. 3, the stepped protrusion 7 of the insulating gasket 2 is inserted into the lower end of the insulating gasket 4 in a tight fit, and the inner diameter of the lower end of the insulating gasket 4 is 0.2mm to 0.3mm smaller than the outer diameter of the stepped protrusion 7 of the insulating gasket 2.
FIG. 4 is a schematic view showing the shape of the sealing insulating pad; the insulating pad 4 is made of a rigid insulating material, and comprises nylon, polypropylene, polytetrafluoroethylene or epoxy resin; the insulating sealing gasket 2 is made of high-quality insulating rubber and is made of ethylene propylene diene monomer or silicon rubber.
The sacrificial anode rod is made of magnesium alloy or aluminum alloy.