Unloading valve
By designing a simple unloading valve structure, gas pressure relief is achieved through stepped channels and moving seals within the housing. This solves the problems of complex structure and cumbersome assembly in existing unloading valves, reduces costs, and enhances market competitiveness.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HEBI JINKE ELECTRIC APPLIANCE CO LTD
- Filing Date
- 2025-05-15
- Publication Date
- 2026-05-01
AI Technical Summary
Existing unloading valves have complex structures, are cumbersome to assemble, and are expensive, making it difficult to meet market demands.
A relief valve comprising a housing, a limiting platform, a guide seal, and a push rod is designed. The housing has a stepped cylindrical channel, and the guide seal and push rod can move up and down to block or open the channel. Combined with the pressure relief port, gas pressure is released, and a simple locking assembly is used for fixation.
This has resulted in a simple structure and convenient assembly of the unloading valve, reducing manufacturing costs and enhancing market competitiveness.
Smart Images
Figure CN224187829U_ABST
Abstract
Description
An unloading valve Technical Field
[0001] This utility model belongs to the technical field of pressure switches, specifically relating to an unloading valve. Background Technology
[0002] A pressure switch is a pressure-operated electrical switch used to control the pressure in the air tank of a motor-driven air compressor, ensuring it operates between two preset pressure values. This pressure switch includes an unloading valve to prevent the air compressor from starting under overload. The unloading valves currently used by our company are relatively complex in structure, require cumbersome assembly, and are relatively expensive. Therefore, to increase market share while meeting customer technical requirements, we have developed an unloading valve that is easy to assemble and relatively inexpensive. Summary of the Invention
[0003] This invention provides a low-cost, easy-to-assemble unloading valve.
[0004] The technical solution adopted in this utility model is as follows:
[0005] An unloading valve includes a housing, a limiting platform disposed inside the housing, a guide seal, and a push rod. The housing has a cylindrical channel penetrating the entire housing, the channel being stepped with its inner diameter gradually decreasing from bottom to top. The limiting platform is disposed at the lower part of the cylindrical channel and has a circular through hole in its center. The guide seal and push rod are movably disposed on the limiting platform, capable of moving upwards to block the cylindrical channel from vertical connection, or moving downwards to allow vertical connection. A pressure relief port connected to the cylindrical channel is located on one side of the housing, above the guide seal.
[0006] Preferably, the guide seal has a convex structure with a convex through hole in the center and several support columns spaced circumferentially on the bottom surface. The push rod is movably inserted into the convex through hole of the guide seal, with its upper end extending upward along the cylindrical channel out of the housing and its lower end fitting into the convex through hole. When the push rod moves upward, its lower end can press against and seal the convex through hole, thereby driving the guide seal to move upward together to seal the cylindrical channel and prevent it from communicating vertically. Alternatively, when the push rod moves downward, its lower end moves downward without sealing the convex through hole, thereby allowing the cylindrical channel to communicate vertically.
[0007] Preferably, the top rod is a rod with a conical truncated platform at the lower end. The diameter of the conical truncated platform is larger than the inner diameter of the circular through hole of the limiting platform and smaller than the inner diameter of the large diameter end of the convex through hole of the guide seal. The height of the conical truncated platform is smaller than the height of the large diameter end of the convex through hole.
[0008] Preferably, the lower end of the housing is threadedly connected to a locking assembly, which includes a locking nut and an inner sleeve. The inner sleeve is disposed inside the locking nut, and its top surface is lower than the top surface of the locking nut. An annular cavity is formed between the locking nut and the inner sleeve to cooperate with the lower end of the housing.
[0009] Preferably, the locking nut has a limiting step on the inner side of the end away from the housing, and a chamfer is formed at the lower opening of the locking nut. The inner sleeve passes through the inside of the locking nut and has a boss on its outer side that mates with the limiting step. Its lower end forms an edge that mates with the chamfer of the locking nut.
[0010] Compared with the prior art, the advantages of this utility model are: this unloading valve has a simple structure, relatively few internal components, is easy to assemble, and has low manufacturing cost. Attached Figure Description
[0011] Figure 1 is a schematic diagram of the structure of this utility model.
[0012] In the diagram: 1. Housing; 2. Limiting platform; 3. Guide seal; 4. Top rod; 5. Cylindrical channel; 6. Circular through hole; 7. Pressure relief port; 8. Convex through hole; 9. Support column; 10. Conical platform; 11. Locking nut; 12. Inner sleeve; 13. Annular cavity; 14. Limiting step; 15. Boss; 16. Edge. Detailed Implementation
[0013] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described below in conjunction with specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the scope of this patent. It is understandable that some well-known structures and their descriptions may be omitted in the drawings for those skilled in the art.
[0014] The unloading valve of this utility model includes a housing 1, a limiting platform 2 disposed inside the housing 1, a guide seal 3, and a push rod 4. The housing is made of metal. A cylindrical channel 5 is provided inside the housing 1, which runs through the entire housing. The cylindrical channel is arranged in a stepped shape, and its inner diameter gradually decreases from bottom to top. The shape design of the cylindrical channel takes into account the arrangement of the limiting platform, guide seal, and push rod, as well as ease of processing. The lower end of the cylindrical channel is the inlet. The limiting platform 2 is located at the lower part of the cylindrical channel 5 of the housing, but at a certain distance from the bottom of the housing. A circular through hole 6 is opened in the center of the limiting platform 2. The limiting platform is a cylindrical plastic part that is interference-fitted with an inner diameter area of the cylindrical channel to prevent the guide seal 3 and the top rod 4 above from falling off. The guide seal 3 and the top rod 4 are movably mounted on the limiting platform 2 and can move up and down. They can move upward to block the cylindrical channel so that it is not connected from top to bottom, or they can move downward to allow the cylindrical channel to be connected from top to bottom. A pressure relief port 7 connected to the cylindrical channel 5 is opened on one side of the housing 1, and the pressure relief port 7 is located above the guide seal 3.
[0015] Specifically, the guide seal and the push rod are designed in a coordinated manner to achieve both sealing and opening of the cylindrical channel. The guide seal 3 and the limiting platform 2 are located in the same inner diameter area of the cylindrical channel 5, with the upper end being a slightly smaller inner diameter area connected to this area. The guide seal 3 is a convex structure made of nitrile rubber, which can move upward under pressure to seal the cylindrical channel. A convex through hole 8 is provided in the center of the guide seal 3, and several support columns 9 are arranged circumferentially on the bottom surface of the guide seal 3. The push rod 4 is movably inserted into the convex through hole 5 of the guide seal 3. Its upper end extends upward along the cylindrical channel 5 and out of the housing 1, while its lower end is adapted to the convex through hole. When the push rod moves upward, the lower end can press against and seal the convex through hole, thereby driving the guide seal to move upward together to seal the cylindrical channel and prevent it from being connected vertically. Alternatively, when the push rod moves downward, the lower end moves downward without sealing the convex channel, thereby allowing the cylindrical channel to be connected vertically.
[0016] Furthermore, the top rod 4 is a rod with a conical platform 10 at its lower end. This conical platform is adapted to the convex through hole of the guide seal. When the rod moves upward, the lower end can press against and seal the convex through hole. The diameter of the conical platform 10 is larger than the inner diameter of the circular through hole 6 of the limiting platform, and smaller than the inner diameter of the large-diameter end of the convex through hole 5 of the guide seal. The height of the conical platform 10 is smaller than the height of the large-diameter end of the convex through hole 5. The design of the lower conical platform also ensures that the rod will not fall out of the circular through hole of the limiting platform, nor will it be pushed out of the convex through hole of the guide seal.
[0017] During assembly, the guide seal and push rod are first installed into the cylindrical channel from the lower end of the housing. Then, the housing is inverted, and the limiting platform is pressed into the set position of the cylindrical channel by the workpiece. Since the limiting platform and the cylindrical channel are interference-fitted, their position is fixed and used to support the guide seal and push rod and prevent them from falling out.
[0018] Figure 1 shows a schematic diagram of the unloading valve under pressure. When there is no pressure, the guide seal and the push rod move relative to each other in the cylindrical channel. In use, the unloading valve 1 is positioned as shown in Figure 1. Under appropriate pressure, the push rod moves rapidly upwards to block the convex through-hole and drives the guide seal to move rapidly upwards to jointly block the cylindrical channel, preventing vertical communication and thus preventing the lower gas from passing through. When an external force is applied to the top of the push rod, the push rod moves downwards and separates from the guide seal. When the push rod moves downwards but does not contact the limiting platform, the air passage remains open. Gas rises along the air passage and is led out from the pressure relief port for pressure relief. During this process, the guide seal also gradually falls until the conical platform of the push rod falls to block the circular through-hole of the limiting platform, stopping the pressure relief. Due to the support column and the structure of the guide seal itself, the air passage above the conical platform remains open, and excess gas overflows from this air passage through the pressure relief port.
[0019] Specifically, the unloading valve is mounted on the pressure switch. The pressure switch disconnects the power supply to the air compressor cylinder. Simultaneously, the opening of the pressure switch causes the unloading valve to release air from the cylinder. This prevents the cylinder from becoming trapped and unable to start when it begins to operate. When the air compressor starts, the pressure switch closes, blocking the unloading valve's cylindrical passage and preventing air release. When the disconnect pressure value is reached, the pressure switch opens, and at the same time, components on the pressure switch push open the unloading valve's push rod, releasing air from the valve. This is one cycle.
[0020] To facilitate the fixing of the unloading valve to the pipe body, a locking assembly is threadedly connected to the lower end of the housing 1. The locking assembly includes a locking nut 11 and an inner sleeve 12. The inner sleeve 12 is disposed inside the locking nut 11, and its top surface is lower than the top surface of the locking nut 11. An annular cavity 13 is formed between the locking nut 11 and the inner sleeve 12, which mates with the lower end of the housing. The upper inner side of the locking nut 11 has an internal thread that mates with the housing. In Figure 1, the overlapping part between the locking nut and the housing is the part where the internal and external threads mate. To clearly see the structure of the inner ring, Figure 1 shows the undeformed inner ring structure, so it partially overlaps with the housing. In reality, after being screwed into the lower end of the housing, the inner ring will be squeezed and contracted inward.
[0021] Specifically, the locking nut 11 has a limiting step 14 on the inner side of the end away from the housing, and a chamfer is formed at the lower opening of the locking nut. The inner sleeve 12 is inserted inside the locking nut 11, and has a boss 15 on its outer side that cooperates with the limiting step 14. Its lower end forms an edge 16 that cooperates with the chamfer of the locking nut.
[0022] When in use, first insert the tube body into the inner sleeve of the locking assembly, and then screw the unloading valve into the annular cavity of the locking assembly from the top thread. When screwing it in downward, the housing will squeeze the inner sleeve inward, and the inner ring will shrink and deform, locking the tube body.
Claims
1. An unloading valve characterized by: The device includes a housing, a limiting platform, a guide seal, and a push rod disposed inside the housing. The housing has a cylindrical channel extending through the entire housing, the channel being stepped with its inner diameter gradually decreasing from bottom to top. The limiting platform is located at the lower part of the cylindrical channel and has a circular through hole in its center. The guide seal and push rod are movably disposed on the limiting platform, capable of moving upwards to block the cylindrical channel from top to bottom, or moving downwards to allow the cylindrical channel to connect top to bottom. A pressure relief port connected to the cylindrical channel is located on one side of the housing, above the guide seal.
2. The unloader valve of claim 1, wherein: The guide seal has a convex structure with a convex through hole in the center. Several support columns are spaced apart circumferentially on the bottom surface of the guide seal. The push rod is movably inserted into the convex through hole of the guide seal. Its upper end extends upward along the cylindrical channel out of the housing, and its lower end is adapted to the convex through hole. When the push rod moves upward, its lower end can press against and seal the convex through hole, thereby driving the guide seal to move upward together to seal the cylindrical channel so that it is not connected vertically. Alternatively, when the push rod moves downward, its lower end moves downward without sealing the convex through hole, thereby allowing the cylindrical channel to be connected vertically.
3. The unloading valve according to claim 1, characterized in that: The top rod is a rod with a conical truncated platform at the lower end. The diameter of the conical truncated platform is larger than the inner diameter of the circular through hole of the limiting platform and smaller than the inner diameter of the large diameter end of the convex through hole of the guide seal. The height of the conical truncated platform is smaller than the height of the large diameter end of the convex through hole.
4. The unloading valve according to claim 1, characterized in that: The lower end of the housing is threadedly connected to a locking assembly, which includes a locking nut and an inner sleeve. The inner sleeve is disposed inside the locking nut, and its top surface is lower than the top surface of the locking nut. An annular cavity is formed between the locking nut and the inner sleeve to cooperate with the lower end of the housing.
5. The unloader valve of claim 4, wherein: The locking nut has a limiting step on the inner side of the end away from the housing, and a chamfer is formed at the lower opening of the locking nut. The inner sleeve passes through the inside of the locking nut and has a boss on its outer side that mates with the limiting step. Its lower end forms an edge that mates with the chamfer of the locking nut.