Hydraulic cylinder type buffer device

Abstract

A hydraulic cylinder-type buffer device includes a hydraulic cylinder, a T-shaped piston rod, a relay oil tank, an oil cooler, a sealing block, and a pad. The hydraulic cylinder includes a cylinder body with a first annular boss and a second annular boss on its inner side. An annular gap is formed between the T-shaped piston rod and the second annular boss. The hydraulic cylinder has a first oil inlet, a second oil inlet, an oil outlet, and a vent. The relay oil tank communicates with the inner cavity of the hydraulic cylinder through the vent, the oil outlet, and the second oil inlet. The oil cooler communicates with the inner cavity of the hydraulic cylinder through the first oil inlet. The sealing block is fixed to the top opening of the hydraulic cylinder. The bottom of the pad is fixed to the top of the T-shaped piston rod and slidably installed within the sealing block. This design prevents wear and provides a buffering effect.

Description

Hydraulic cylinder type buffer device Technical Field

[0001] This invention relates to the field of punch presses, and in particular to a hydraulic cylinder-type buffer device. Prior Technology

[0002] In the field of stamping, products are subjected to instantaneous stamping pressure, which can easily cause wrinkles or breakage. The usual practice is to install a die pad under the stamping press table or between the upper and lower dies to buffer the huge pressure generated during stamping, thereby improving the stamping quality of the product.

[0003] However, existing mold pad buffer devices have complex structures, short service lives, and high replacement costs. Furthermore, they exert significant forces on the ground, limiting their applicability to punch presses. Therefore, there is an urgent need to develop a novel buffer device for use in the punch press field. Summary of the Invention

[0004] Therefore, one of the objectives of this invention is to provide a hydraulic cylinder-type buffer device that solves the problem of cracks or unevenness that easily occur in products under instantaneous stamping conditions.

[0005] Therefore, this novel hydraulic cylinder-type buffer device includes:

[0006] A hydraulic cylinder includes a cylinder body, on the inner side of which a first annular boss and a second annular boss are integrally formed at intervals, and the cylinder body defines an inner cavity of the hydraulic cylinder;

[0007] A T-shaped piston rod is disposed inside the cylinder cavity and has a lower end, wherein an annular gap is formed between the lower end of the T-shaped piston rod and the second annular boss;

[0008] The cylinder is equipped with a first oil inlet, a second oil inlet, an oil outlet, and a vent, all connected to the cylinder's internal cavity.

[0009] A relay oil tank, which communicates with the inner cavity of the oil cylinder through the vent, the oil outlet, and the second oil inlet;

[0010] An oil cooler, which communicates with the inner cavity of the oil cylinder through the first oil inlet;

[0011] A sealing block, which is fixed at the top opening of the cylinder; and

[0012] A pad block, the bottom of which is fixed to the top of the T-shaped piston rod, and which is slidably installed inside the sealing block.

[0013] In some embodiments, the first oil inlet and the oil outlet are both located between the first annular boss and the second annular boss, and the first oil inlet and the oil outlet are located at different peripheral positions of the cylinder body; the cylinder also includes a cylinder base fixed to the bottom of the cylinder body, and the second oil inlet is located on the cylinder base; the vent is located in the cylinder body and the vent is located above the first annular boss.

[0014] In some embodiments, the cylinder body has a first oil inlet channel connected to the first oil inlet, and a first check valve is connected to the outside of the first oil inlet; the cylinder base has a second oil inlet channel connected to the second oil inlet, and a second check valve is connected to the outside of the second oil inlet; the cylinder body has a first gas channel connected to the vent; and the cylinder body has an oil outlet pipe connected to the oil outlet.

[0015] In some embodiments, the annular gap ranges from 0.03 to 0.05 mm.

[0016] In some embodiments, the cylinder-type buffer device further includes a pressure regulating valve and an air source. The pressure regulating valve is connected to the upper part of the relay oil tank through a gas pipeline, and the air source is connected to the pressure regulating valve through the gas pipeline.

[0017] In some embodiments, the cylinder further includes an annular wear-resistant ring and an annular sealing ring that are sequentially and spaced apart on the surface of the first annular boss.

[0018] In some embodiments, the relay oil tank is connected to the oil cooler, and the relay oil tank delivers its internal hot hydraulic oil to the oil cooler for cooling.

[0019] In some implementations, the opening pressure range of the second check valve is 0.5-0.6 MPa.

[0020] In some implementations, the compressed air pressure in the relay tank ranges from 0.40 to 0.45 MPa.

[0021] In some embodiments, the lower end of the T-shaped piston rod is a brazed copper surface.

[0022] This invention has at least the following advantages:

[0023] 1. This novel design utilizes annular gap throttling to build pressure. The second oil inlet of the buffer zone is connected to a second one-way valve. When the T-shaped piston rod moves downward under pressure, the hydraulic oil in the buffer zone can only be squeezed upward through the annular gap between the T-shaped piston rod and the second annular boss of the cylinder due to the one-way valve, and enter the heat exchange zone. It is precisely the setting of the annular gap at the T-shaped piston rod connected to the pad block that avoids wear between the cylinder and piston of the same material. Under huge impact force, the hydraulic oil in the buffer zone seeps upward, achieving the technical effect of oil pressure buffering.

[0024] 2. This new type of device is equipped with a relay oil tank. The compressed air in the relay oil tank is kept in communication with the gas inside the cylinder. When the T-shaped piston rod is compressed and descends, the gas located below the T-shaped piston rod is slowly discharged into the relay oil tank through the vent, which also plays a role in gas buffering. In addition, when the relay oil tank is not working, the compressed air left above it can provide back pressure for the cylinder, ensuring that the hydraulic oil in the pipeline and the cylinder is full. This prevents the hydraulic oil in the pipeline from entering the relay oil tank under the action of gravity, thus avoiding the situation where the pressure cannot be built up in the next operation. It also eliminates the need for the relay oil tank to be higher than the shock absorption device.

[0025] 3. The hot oil inside the cylinder of this new type flows out through the oil outlet to the intermediate oil tank and then to the oil cooler. The oil cooler cools the hot oil, and the cooled oil is injected back into the cylinder. The above-mentioned oil circuit avoids the situation of excessively high oil temperature inside the cylinder.

[0026] 4. The lower end of the T-shaped piston rod of this new type adopts a copper welding process, which also avoids wear between the cylinder and piston of the same material, thus improving the durability of the device. Simple Explanation of the Diagram

[0027] Other features and effects of this invention will be clearly presented in the embodiments with reference to the drawings, wherein: Figure 1 is a structural schematic diagram of a specific embodiment of the novel hydraulic cylinder-type buffer device; Figure 2 is a cross-sectional view taken along direction AA in Figure 1; and Figure 3 is another structural schematic diagram of this specific embodiment. Implementation

[0028] Before this invention is described in detail, it should be noted that similar elements are represented by the same reference numerals in the following description.

[0029] Referring to Figures 1 to 3, a specific embodiment of the novel hydraulic cylinder type buffer device includes a hydraulic cylinder 100 and a T-shaped piston rod 200.

[0030] The hydraulic cylinder 100 includes a cylinder body 1 and a cylinder base 2. The cylinder body 1 has an integrally formed first annular boss 11 and a second annular boss 12 spaced apart on its inner side. The cylinder base 2 is fixed to the lower surface of the second annular boss 12 at the bottom of the cylinder body 1 by screws. The cylinder body 1 defines a cylinder cavity 10. The first annular boss 11 and the second annular boss 12 constitute the cylinder cavity diameter D1.

[0031] The T-shaped piston rod 200 is slidably mounted in the inner cavity 10 of the cylinder body 1. The T-shaped piston rod 200 has a lower end 201 with a lower end diameter D2. An annular gap d is formed between the lower end 201 of the T-shaped piston rod 200 and the second annular boss 12 of the cylinder body 1. The annular gap d is equal to the inner cavity diameter D1 of the cylinder body and the lower end diameter D2. The value range of the annular gap d is 0.03-0.05 mm. This value range not only provides a better hydraulic oil output rate and ensures the oil pressure buffering effect, but also avoids wear between the cylinder body 1 and the T-shaped piston rod 200, which are made of the same material, thus improving the service life of the device. At this time, the first annular boss 11, the second annular boss 12, the T-shaped piston rod 200, and the cylinder base 2 divide the inner cavity 10 of the cylinder into different areas. The area between the first annular boss 11 and the second annular boss 12 of the cylinder body 1 and the outer surface of the T-shaped piston rod 200 forms a heat exchange area 101. The bottom of the T-shaped piston rod 200 and the cylinder base 2 form a hydraulic pressure buffer area 102. The upper part of the T-shaped piston rod 200 and the first annular boss 11 form a pneumatic pressure buffer area 103.

[0032] The cylinder-type buffer device also includes a sealing block 300 fixedly disposed at the top opening of the cylinder 100. The sealing block 300 is fixedly connected to the opening of the cylinder 100 by screws. The sealing block 300 is used to seal the upper part of the cylinder cavity 10. A through groove 301 is formed in the middle of the sealing block 300. The cylinder-type buffer device also includes a pad 400. The pad 400 passes through the through groove 301 and its bottom is fixedly connected to the top of the T-shaped piston rod 200, and is slidably connected in the through groove 301 of the sealing block 300. During operation, the upper surface of the pad 400 can be used to place a product to be stamped (not shown). When the product to be stamped is stamped by a huge stamping force, the pad 400 is controlled to drive the T-shaped piston rod 200 to move slowly downward in the cylinder cavity 10, thereby playing a buffering function.

[0033] To achieve the buffering function of the hydraulic cylinder 100, the hydraulic cylinder-type buffer device further includes a relay oil tank 500, a pressure regulating valve 600, and an air source 700 connected to the hydraulic cylinder 100. A gas pipeline 800 is connected to the upper part of the relay oil tank 500. The pressure regulating valve 600 is installed on the gas pipeline 800. The pressure regulating valve 600 is connected to the upper part of the relay oil tank 500 through the gas pipeline 800. The air source 700 is connected to the pressure regulating valve 600 through the gas pipeline 800. The air source 700 is used to supply compressed air to the relay oil tank 500. The relay oil tank 500 includes a compressed air section 501 and a hydraulic oil section 502. The compressed air section 501 and the hydraulic oil section 502 of the relay oil tank 500 are respectively connected to the inner cavity 10 of the hydraulic cylinder through a gas pipeline 503 and an oil pipeline 504. Specifically, a vent 13 is provided at the upper part of the cylinder body 1 of the hydraulic cylinder 100, communicating with the inner cavity 10 of the hydraulic cylinder. The vent 13 is positioned above the first annular boss 11. A first gas passage 14 is provided inside the cylinder body 1, communicating with the vent 13. One side of the vent 13 is connected to the air pressure buffer area 103 through the first gas passage 14. The other side of the vent 13 is connected to the compressed air section 501 of the relay oil tank 500 through the gas pipe 503. An oil outlet 15 is provided at the lower part of the cylinder body 1, communicating with the inner cavity 10 of the hydraulic cylinder. The oil outlet 15 is positioned between the first annular boss 11 and the second annular boss 12. An oil outlet pipe 16 is provided inside the cylinder body 1, communicating with the oil outlet 15. One side of the oil outlet 15 is connected to the heat exchange area 101 through the oil outlet pipe 16, and the other side of the oil outlet 15 is connected to the hydraulic oil section 502 of the relay oil tank 500 through the oil passage pipe 504.

[0034] The hydraulic oil section 502 of the relay oil tank 500 is also connected to the hydraulic pressure buffer area 102 via another oil line pipe 505. Specifically, the cylinder base 2 of the cylinder 100 is provided with a second oil inlet 21 communicating with the inner cavity 10 of the cylinder, and a second oil inlet channel 22 communicating with one side of the second oil inlet 21 is provided inside the cylinder base 2. A second check valve 23 is also connected to the other side of the second oil inlet 21. The second check valve 23 is a spring-loaded check valve (this is prior art and will not be described in detail), and the second check valve 23 is connected to the hydraulic oil section 502 via the oil line pipe 505. Through the above-mentioned pipeline configuration, the hydraulic oil of the relay oil tank 500 is injected into the hydraulic pressure buffer area 102 during the return phase of the T-shaped piston rod 200 to store the amount of oil required for the next pressing phase.

[0035] Due to the reciprocating motion of the T-shaped piston rod 200, the hydraulic oil inside the cylinder 100 will continuously heat up. If the hydraulic oil cannot be cooled, the cylinder 100 will not function. To prevent the oil temperature inside the cylinder 100 from becoming too high, the cylinder-type buffer device also includes an oil cooler 900 that works in conjunction with the cylinder 100. Specifically, a first oil inlet 17 is provided at the lower part of the cylinder body 1, communicating with the inner cavity 10 of the cylinder. The first oil inlet 17 is positioned between the first annular boss 11 and the second annular boss 12, and the first oil inlet 17 and the oil outlet 15 are located at different circumferential positions of the cylinder body 1. A first oil inlet channel 18 is provided inside the cylinder body 1, communicating with the first oil inlet 17. One side of the first oil inlet 17 is connected to the heat exchange area 101 through the first oil inlet channel 18. A first one-way valve 19 is connected to the other side of the first oil inlet 17. The first check valve 19 is a spring-loaded check valve (this is prior art and will not be described further). The first check valve 19 is connected to the oil outlet of the oil cooler 900 via an oil pipe 901. Furthermore, the oil inlet of the oil cooler 900 is connected to the oil outlet of the intermediate oil tank 500. In actual operation, the hot oil pressed out from the cylinder cavity 10 is discharged to the intermediate oil tank 500, which then flows back to the oil cooler 900. After being cooled by the oil cooler 900, the oil is then input back into the cylinder cavity 10 via the first oil inlet 17. This cycle continues, completing the cooling of the hydraulic oil in the cylinder 100.

[0036] To achieve unidirectional conduction of the second one-way valve 23, in this specific embodiment, the compressed air pressure range in the relay oil tank 500 is 0.4-0.45 MPa, and the conduction pressure range of the second one-way valve 23 is 0.5-0.55 MPa. After the T-shaped piston rod 200 is stamped, the pressure in the oil pressure buffer area 102 and the air pressure buffer area 103 is relatively high due to space compression. Therefore, the T-shaped piston rod 200 begins to move upwards back. Since the air pressure buffer area 103 flows some compressed air into the relay oil tank 500, the compressed air pressure in the relay oil tank 500 increases accordingly, causing the second one-way valve 23 to conduct, and the relay oil tank 500 quickly replenishes oil to the buffer area.

[0037] In this specific embodiment, the oil supply pressure of the oil cooler 900 is about 20 MPa, and the conduction pressure of the first one-way valve 19 is less than the oil supply pressure.

[0038] More specifically, in order to achieve the airtightness of the air pressure buffer area 103, the cylinder 100 also includes an annular wear-resistant ring 111 and an annular sealing ring 112 installed sequentially at intervals on the surface of the first annular boss 11 to ensure the airtightness of the gas in the cylinder cavity 10. The oil passage and air passage in the cylinder cavity 10 are isolated.

[0039] More specifically, the lower end 201 of the T-shaped piston rod 200 is made of brazed copper. The copper material can enhance and reduce the wear of the T-shaped piston rod 200 at the annular gap d, thereby improving its service life.

[0040] The working principle of this novel hydraulic cylinder-type buffer device is as follows:

[0041] First, the product to be stamped is placed on the upper surface of the pad 400. When the product is stamped under a large stamping force, the pad 400 controls the T-shaped piston rod 200 to move slowly downward within the cylinder cavity 10. Since compressed air is located below the T-shaped portion of the T-shaped piston rod 200 and hydraulic oil is located at the bottom of the T-shaped piston rod 200, when the T-shaped piston rod 200 descends rapidly, compressed air is discharged from the cylinder cavity 10 to the compressed air section 501 of the intermediate oil tank 500. The slow discharge rate provides a pressure buffering function. Simultaneously, when the T-shaped piston rod 200 descends, hydraulic oil is discharged from the bottom of the cylinder 100 to the heat exchange area 101, and then from the heat exchange area 101 to the hydraulic oil section 502 of the intermediate oil tank 500. The annular gap d of 0.03-0.05 mm provides an oil pressure buffering function for the hydraulic oil. Secondly, after the product is stamped, the pressure in the hydraulic buffer zone 102 and the pneumatic buffer zone 103 is relatively high due to the compression of space. Therefore, the T-shaped piston rod 200 automatically moves upward back. As the pneumatic buffer zone 103 discharges compressed air into the relay oil tank 500, the compressed air pressure in the relay oil tank 500 increases, causing the second one-way valve 23 to open, and the relay oil tank 500 quickly replenishes oil to the buffer zone.

[0042] In addition, the oil cooler 900 cools the hot hydraulic oil flowing out of the relay oil tank 500 and then flows into the heat exchange area 101 through the first oil inlet 17, continuously replenishing the inside of the cylinder 100 with cold oil and reducing the temperature of the hydraulic oil in the cylinder 100.

[0043] However, the above description is merely an embodiment of this invention and should not be construed as limiting the scope of implementation of this invention. Any simple equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the patent specification shall still fall within the scope of this invention.

[0044] 100: Hydraulic Cylinder 1: Cylinder block 10: Cylinder inner cavity 101: Heat exchange area 102: Hydraulic Buffer Zone 103: Pressure Buffer Zone 11: First annular boss 111: Annular Wear-Resistant Ring 112: Annular sealing ring 12: Second annular boss 13: Vent 14: First gas passage 15: Oil outlet 16: Oil outlet pipe 17: First oil inlet 18: First oil inlet channel 19: First check valve 2: Hydraulic cylinder base 21: Second oil inlet 22: Second oil inlet channel 23: Second check valve 200: T-type piston rod 201: Lower end 300: Sealing block 301: Through groove 400: Spacer 500: Relay fuel tank 501: Compressed Air Section 502: Hydraulic oil section 503: Gas Pipeline 504: Oil pipeline 505: Oil pipeline 600: Air pressure regulating valve 700: Gas Source 800: Gas Pipeline 900: Oil Cooler 901: Oil pipeline d: Annular gap D1: Cylinder body diameter D2: Diameter of the lower end

Claims

1. A hydraulic cylinder-type buffer device, comprising: A hydraulic cylinder includes a cylinder body with a first annular protrusion and a second annular protrusion integrally formed on the inner side of the cylinder body, the cylinder body defining a hydraulic cylinder cavity; a T-shaped piston rod disposed in the hydraulic cylinder cavity and having a lower end, the lower end of the T-shaped piston rod forming an annular gap with the second annular protrusion; the hydraulic cylinder interior is provided with a first oil inlet, a second oil inlet, an oil outlet, and a vent; a relay oil tank communicating with the hydraulic cylinder cavity through the vent, the oil outlet, and the second oil inlet; an oil cooler communicating with the hydraulic cylinder cavity through the first oil inlet; a sealing block fixedly disposed at the top opening of the hydraulic cylinder; and a pad whose bottom is fixedly connected to the top of the T-shaped piston rod and slidably installed within the sealing block.

2. The hydraulic cylinder type buffer device as described in claim 1, wherein, The first oil inlet and the oil outlet are both located between the first annular boss and the second annular boss, and the first oil inlet and the oil outlet are located at different circumferential positions of the cylinder body; the cylinder also includes a cylinder base fixed to the bottom of the cylinder body, and the second oil inlet is located on the cylinder base; the vent is located in the cylinder body and the vent is located above the first annular boss.

3. The hydraulic cylinder type buffer device as described in claim 2, wherein, The cylinder body has a first oil inlet channel connected to the first oil inlet, and a first check valve is connected to the outside of the first oil inlet; the cylinder base has a second oil inlet channel connected to the second oil inlet, and a second check valve is connected to the outside of the second oil inlet; the cylinder body has a first gas channel connected to the vent; and the cylinder body has an oil outlet pipe connected to the oil outlet.

4. The hydraulic cylinder type buffer device as described in claim 1, wherein, The numerical range of this annular gap is 0.03-0.05 mm.

5. The hydraulic cylinder type buffer device according to any one of claims 2 to 4 further includes a pressure regulating valve and a gas source, the pressure regulating valve being connected to the upper part of the relay oil tank via a gas pipeline, and the gas source being connected to the pressure regulating valve via the gas pipeline.

6. The hydraulic cylinder type buffer device as described in claim 1, wherein, The cylinder also includes an annular wear-resistant ring and an annular sealing ring that are sequentially and spaced apart on the surface of the first annular boss.

7. The hydraulic cylinder type buffer device as described in claim 1, wherein, The relay oil tank is connected to the oil cooler, and the relay oil tank delivers its internal hot hydraulic oil to the oil cooler for cooling.

8. The hydraulic cylinder type buffer device as described in claim 3, wherein, The opening pressure range of the second check valve is 0.5-0.6 MPa.

9. The hydraulic cylinder type buffer device as described in claim 8, wherein, The compressed air pressure range in the relay tank is 0.40-0.45 MPa.

10. The hydraulic cylinder type buffer device as claimed in claim 1, wherein, The lower end of the T-shaped piston rod is a brazed copper surface.

Images