Overload protection valve for press machine
By designing a constant-proportional unloading overload protection valve on the press, the oil replenishment port check valve, cover plate check valve and pilot piston can achieve automatic overload protection, which solves the problem of manual adjustment and time-consuming and safety hazards, and improves the device diversified and secure.
Patent Information
- Application Number
- CN202421195798.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-29
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-05-29
Smart Images
Figure CN222326528U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of protection valves, and in particular relates to an overload protection valve for a press. Background Art
[0002] A press (including punching machines and hydraulic presses) is a versatile press with an ingenious structure. It has a wide range of uses and high production efficiency. It can be widely used in cutting, punching, blanking, bending, riveting and forming processes. It processes metal blanks into parts by applying strong pressure to them to cause plastic deformation and fracture.
[0003] To ensure the safe use of the press, an overload protection mechanism is set up on the press, which is usually an overload protection valve; the overload protection valve is a valve body controlled by mechanical or electrical components, which is closed and sealed within the normal working pressure range. When the load exceeds the specified value, the overload protection valve will automatically open to reduce the system pressure and thus protect the device.
[0004] At present, for the overload protection valve used in the press, when using molds of different tonnages, it is necessary to set different overload pressures on the overload protection valve to protect the mold. The overload protection valve in the prior art mostly requires manual adjustment of the overload pressure of the overload protection valve. In this process, not only is the manual adjustment laborious and time-consuming, but there are also certain safety hazards, which cannot meet the use requirements. For this reason, we provide an overload protection valve that uses a fixed-proportional unloading method to complete overload protection, that is, the pre-filled oil pressure is set in proportion, and when the cylinder pressure exceeds the proportion of the press tonnage, the overload protection valve opens to release the pressure to ensure safety. At the same time, different proportions of equipment can be selected according to different use requirements, which greatly improves the functionality of the device and effectively meets the use requirements of the overload protection valve for the press. Utility Model Content
[0005] In view of the above-mentioned technical problems, the utility model proposes an overload protection valve for a press machine which has a reasonable design, a simple structure, is easy to process and adopts a proportional unloading method. On the one hand, it can be conveniently adjusted according to different usage requirements to increase the diversification of equipment usage; on the other hand, it also reduces the danger, ensures safe use, and effectively meets the usage requirements.
[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is an overload protection valve for a press machine, comprising an overload protection valve body, the overload protection valve body comprising a unloading block, a unloading cover plate is arranged on the unloading block, a two-way plug-in is arranged in the unloading block, a safety cylinder interface is arranged in the unloading block located on one side of the two-way plug-in, an oil replenishment port is opened on one side of the unloading block, an oil replenishment check valve is arranged on the path connecting the oil replenishment port and the safety cylinder interface, the unloading cover plate comprises a two-way cover plate, a pilot cover plate is arranged on one side of the two-way cover plate, a cover plate check valve is arranged in the two-way cover plate, a first screw plug is arranged on one side of the cover plate check valve, a pilot piston is arranged in the pilot cover plate, a second screw plug is arranged on one side of the pilot piston, and a check valve push rod is arranged on the other side of the pilot piston and passes through the two-way cover plate.
[0007] Preferably, a piston return spring is provided in the pilot cover plate and is sleeved on the outer periphery of the one-way valve push rod and is located on one side of the pilot piston.
[0008] Preferably, an oil passage is provided in the unloading block and is connected to one side of a cover plate one-way valve located in the two-way cover plate.
[0009] Preferably, the ratio of the area of the pilot piston to the area of the cover plate one-way valve is 1:2.
[0010] Compared with the prior art, the advantages and positive effects of the utility model are:
[0011] 1. The utility model provides an overload protection valve for a press machine. By setting an oil replenishing port one-way valve, a cover plate one-way valve, a one-way valve push rod and a pilot piston, especially setting the area ratio between the pilot piston and the cover plate one-way valve to a fixed ratio, a fixed-proportion unloading method is adopted. No adjustment setting is required. Only the pre-filling oil pressure needs to be set proportionally, which reduces the possibility of manual adjustment, ensures safety in use, reduces labor intensity to a certain extent, and meets use requirements. The device has a reasonable design, a simple structure, and is easy to process. It adopts a proportional unloading method. On the one hand, it can be conveniently adjusted according to different use requirements to increase the diversification of equipment use. On the other hand, it also reduces the risk, ensures safety in use, and effectively meets use requirements. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.
[0013] Figure 1It is a structural schematic diagram of an overload protection valve for a press;
[0014] Figure 2 It is a schematic diagram of a partial internal structure of an overload protection valve for a press;
[0015] Figure 3 This is a schematic diagram of the structural principle of an overload protection valve for a press;
[0016] Figure 4 It is a schematic diagram of the internal structure of the unloading cover plate;
[0017] Figure 5 It is a top view schematic diagram of the internal structure of the two-way cover plate;
[0018] Figure 6 It is a schematic cross-sectional diagram of the internal structure of the unloading block at the plane where the oil filling port is located;
[0019] Figure 7 The figure is a working principle diagram of an overload protection valve for a press;
[0020] In the above figures, 1, unloading block; 1a, safety cylinder interface; 1b, oil supply port; 1c, oil channel; 2, unloading cover plate; 21, two-way cover plate; 211, cover plate one-way valve; 212, first screw plug; 22, pilot cover plate; 221, pilot piston; 222, second screw plug; 223, one-way valve push rod; 3, two-way plug-in; 4, oil supply one-way valve; 5, piston return spring. DETAILED DESCRIPTION
[0021] In order to more clearly understand the above-mentioned purpose, features and advantages of the utility model, the utility model is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.
[0022] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.
[0023] Examples, such as Figure 1 to Figure 7As shown, an overload protection valve for a press comprises an overload protection valve body, the overload protection valve body comprises a unloading block 1, a unloading cover plate 2 is arranged on the unloading block 1, a two-way plug-in 3 is arranged in the unloading block 1, wherein an oil return port is provided below the two-way plug-in 3, a safety cylinder interface 1a is provided in the unloading block 1 on one side of the two-way plug-in 3, an oil replenishment port 1b is provided on one side of the unloading block 1, wherein the oil replenishment port 1b is opposite to the safety cylinder interface 1a, and an oil replenishment check valve 4 is provided on the path connecting the oil replenishment port 1b and the safety cylinder interface 1a, in addition, vertical channels are provided in the unloading block 1 on both sides of the safety cylinder interface 1a, one of the vertical channels is connected to the safety cylinder interface 1a and extends to the two-way cover plate 21, and a channel is provided in the two-way cover plate 21 to connect the path with the spring chamber of the cover plate check valve 211, to ensure oil The liquid can enter and ensure that the two-way plug 3 is in a closed state. The other vertical channel is similar, except that the end of the two-way cover plate 21 is set up in an inclined path and extends to the pilot cover plate 22. The end of the two-way cover plate 21 is connected and corresponds to the end of the pilot piston 221 to ensure that the pilot piston 221 can be actuated when the pressure of the safety cylinder increases, providing convenient conditions for the realization of overload unloading action. The unloading cover plate 2 includes a two-way cover plate 21, a pilot cover plate 22 is arranged on one side of the two-way cover plate 21, a cover plate check valve 211 is arranged in the two-way cover plate 21, a first screw plug 212 is arranged on one side of the cover plate check valve 211, a pilot piston 221 is arranged in the pilot cover plate 22, a second screw plug 222 is arranged on one side of the pilot piston 221, and a check valve push rod 223 is arranged on the other side of the pilot piston 221, and passes through the two-way cover plate 21;
[0024] The specific working principle and working method are described as follows:
[0025] Safety cylinder oil filling: pressure oil enters the overload protection valve group from the oil replenishment port 1b, and the oil enters the safety hydraulic cylinder through the oil replenishment check valve 4. At the same time, the oil enters the spring chamber of the cover plate check valve 211, and the spring chamber is connected to the valve spring chamber of the two-way plug-in 3. The two-way plug-in 3 is closed, and the safety cylinder oil is pressurized;
[0026] Safety cylinder overload unloading: The area ratio of the pilot piston 221 to the cover plate check valve 211 is 1:2. When the press exceeds the tonnage, the safety cylinder pressure increases. When the safety cylinder pressure increases by more than 2 times the oil replenishment pressure, the high-pressure oil enters the right side of the pilot piston 221, pushing the pilot piston 221 to move to the left. The pilot piston 221 pushes open the cover plate check valve 211 with the help of the check valve push rod 223, and the two-way plug 3 spring chamber is connected to the oil return port. The two-way plug 3 valve core moves up, and the safety cylinder A port is connected to the oil return port T, and the safety cylinder is unloaded;
[0027] In the above process: by setting the one-way valve of the oil replenishing port 1b, the cover plate one-way valve 211, the one-way valve push rod 223 and the pilot piston 221, especially the area ratio between the pilot piston 221 and the cover plate one-way valve 211 is a fixed ratio, so that a fixed ratio unloading method is adopted, and no adjustment setting is required, and only the pre-filling oil pressure needs to be set according to the proportion, which reduces the possibility of manual adjustment, ensures safe use, and reduces labor intensity to a certain extent, meeting the use requirements; the device has a reasonable design, a simple structure, and is easy to process and adopts a proportional unloading method. On the one hand, it can be conveniently adjusted according to different use requirements to increase the diversification of equipment use. On the other hand, it also reduces the risk, ensures safe use, and effectively meets the use requirements.
[0028] In order to ensure the rationality of the device, a piston return spring 5 is arranged inside the pilot cover plate 22 and is sleeved on the outer periphery of the one-way valve push rod 223, and is located on one side of the pilot piston 221. The piston return spring 5 is set to reset the pilot piston 221 after unloading by using the spring force after the pilot piston 221 presses it, so as to smoothly carry out the safety cylinder oil filling action.
[0029] In order to ensure the effective implementation of the overload unloading action, an oil channel 1c is opened in the unloading block 1, and is connected to one side of the cover plate one-way valve 211 located in the two-way cover plate 21. This design ensures the balance under the overload protection valve. A branch is also opened on the communication path between the unloading block 1 and the two-way cover plate 21, and is connected to the piston return spring 5 to ensure the convenient return of the pilot piston 221 after unloading, thereby ensuring the use effect.
[0030] In order to ensure that the overload protection valve can effectively play an overload protection effect, the area ratio of the pilot piston 221 to the cover plate one-way valve 211 is 1:2, which is specifically described as: the ratio of the end surface area of the pilot piston 221 close to the one-way valve push rod 223 to the end surface area of the valve core set in the cover plate one-way valve 211 is 1:2. In other words, when the pressure of the safety cylinder rises to more than 2 times the oil replenishment pressure, the overload protection valve can be activated to unload and ensure safety. At this ratio, there is no need to adjust the overload protection valve and only need to set the pre-filled oil pressure proportionally. This greatly improves the functionality of the device and fully meets the use requirements.
[0031] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.
Claims
1. An overload protection valve for a press, comprising an overload protection valve body, the overload protection valve body comprising a relief block, the relief block being provided with a relief cover plate, characterized in that: A two-way plug-in is arranged in the unloading block, a safety cylinder interface is arranged in the unloading block located on one side of the two-way plug-in, an oil replenishing port is opened on one side of the unloading block, an oil replenishing one-way valve is arranged on the path connecting the oil replenishing port and the safety cylinder interface, the unloading cover plate comprises a two-way cover plate, a pilot cover plate is arranged on one side of the two-way cover plate, a cover plate one-way valve is arranged in the two-way cover plate, a first screw plug is arranged on one side of the cover plate one-way valve, a pilot piston is arranged in the pilot cover plate, a second screw plug is arranged on one side of the pilot piston, a one-way valve push rod is arranged on the other side of the pilot piston and passes through the two-way cover plate.
2. An overload protection valve for a press according to claim 1, characterized in that: A piston return spring which is sleeved on the outer periphery of the one-way valve push rod is arranged in the pilot cover plate and is located on one side of the pilot piston.
3. An overload protection valve for a press according to claim 2, characterized in that: An oil passage is provided in the unloading block and is connected with one side of a cover plate one-way valve located in the two-way cover plate.
4. An overload protection valve for a press according to claim 3, characterized in that: The ratio of the area of the pilot piston to the area of the cover plate one-way valve is 1:2.