Low pulsation internal meshing gear pump with built-in air pressure adjustable wave absorbing device

Abstract

The application provides a low-pulsation internal meshing gear pump with built-in air pressure adjustable wave absorbing device, which comprises a pump body, a front pump cover and a rear pump cover connected to both sides of the pump body, a gear ring arranged in the pump body and a gear internally meshed with the gear ring, a floating piston cavity arranged at the bottom of an oil pressing cavity of the pump body, an air pressure adjusting cavity arranged at one side of the floating piston cavity, and a communication cavity formed by the floating piston cavity and the air pressure adjusting cavity in communication; an air pressure adjusting assembly is installed in the air pressure adjusting cavity, the air pressure adjusting assembly adjusts the air pressure in the air pressure adjusting cavity; a floating piston assembly is installed in the floating piston cavity, the communication cavity is filled with suitable gas, the air pressure adjusting assembly detects the air pressure in the communication cavity and adjusts the air pressure, and the floating piston of the floating piston assembly reciprocates under the action of the air pressure to suppress the flow pulsation of the hydraulic oil in the oil pressing cavity.

Description

Technical Field

[0001] This invention relates to the field of internal gear pumps, and more particularly to a low-pulsation internal gear pump with a built-in adjustable air pressure damping device. Background Technology

[0002] Internal gear pumps possess advantages such as simple and compact structure, smooth operation, high efficiency, and insensitivity to oil contamination, making them widely used in various industrial production and hydraulic systems. However, in applications with high requirements for flow pulsation, the flow pulsation of traditional internal gear pumps may not meet the requirements. Flow pulsation in hydraulic systems can affect the smoothness and accuracy of actuator movement, cause system vibration and noise, reduce the service life of hydraulic components, and exacerbate system energy loss. Therefore, there is an urgent need to improve them to further reduce the flow pulsation at the outlet of the internal gear pump, enabling it to meet the requirements of applications with even higher flow pulsation standards. Summary of the Invention

[0003] The purpose of this invention is to provide a low-pulsation internal gear pump with a built-in adjustable air pressure damping device, thereby overcoming the shortcomings of the prior art.

[0004] To address the aforementioned issues, this invention provides a low-pulsation internal gear pump with a built-in adjustable air pressure damping device, comprising a pump body and a front pump cover and a rear pump cover connecting the two sides of the pump body. The pump body is provided with a gear ring and a gear internally meshing within the gear ring. A floating piston chamber is provided at the bottom of the oil pressure chamber of the pump body, and an air pressure regulating chamber is provided on one side of the floating piston chamber. The floating piston chamber and the air pressure regulating chamber are connected to form a communicating cavity.

[0005] A pressure regulating component is installed in the pressure regulating chamber, and the pressure regulating component regulates the gas pressure in the pressure regulating chamber.

[0006] A floating piston assembly is installed inside the floating piston chamber, and the connecting chamber is filled with gas. The gas pressure regulating assembly detects the gas pressure inside the connecting chamber and adjusts the gas pressure. The floating piston of the floating piston assembly reciprocates under the action of gas pressure to suppress the flow pulsation of hydraulic oil in the oil pressure chamber.

[0007] In some embodiments, the floating piston chamber is located inside the pressure regulating chamber along the radial direction, and the side wall of the pressure regulating chamber near the floating piston chamber is provided with a connecting hole that connects to the floating piston chamber.

[0008] In some embodiments, the outer side of the pressure regulating cavity along the radial direction is provided with a pressure regulating component mounting groove for mounting a pressure regulating component, the cross-sectional area of ​​the pressure regulating component mounting groove is larger than the cross-sectional area of ​​the pressure regulating cavity; the groove surface of the pressure regulating component mounting groove is provided with a countersunk through hole communicating with the floating piston cavity.

[0009] In some embodiments, the air pressure regulating assembly includes a fixed side plate, an air pressure regulating piston, and a piston position adjusting component. The piston position adjusting component passes through the fixed side plate and is connected to the air pressure regulating piston. The fixed side plate is installed in the air pressure regulating assembly mounting groove, the air pressure regulating piston is positioned towards the floating piston chamber, and the piston position adjusting component is exposed in the air pressure regulating assembly mounting groove.

[0010] In some embodiments, the pressure regulating piston has a mounting groove on the side facing the fixed side plate, the piezoelectric sheet is mounted in the mounting groove, one end of the wire is connected to the piezoelectric sheet through the mounting groove, and the other end is connected to an external computing and control component to detect the pressure in the communicating cavity.

[0011] In some embodiments, the piston position adjusting component includes an adjusting screw and an adjusting screw head. The adjusting screw is mounted on the fixed side plate through an adjusting screw mounting hole on the fixed side plate. The adjusting screw head includes a T-shaped boss formed by connecting two cylinders of different diameters and a connecting boss connected to the smaller diameter cylinder of the T-shaped boss.

[0012] The end of the adjusting screw facing the air pressure regulating piston is provided with a T-shaped groove for the T-shaped boss to be inserted, and the connecting boss is connected to the air pressure regulating piston.

[0013] In some embodiments, the air pressure regulating assembly further includes an air valve, and an air valve mounting hole is provided on the fixed side plate, through which the air valve is mounted on the fixed side plate.

[0014] In some embodiments, the floating piston cavity is provided with a floating piston assembly mounting groove, which is located on the side of the floating piston cavity near the outside of the pump body, and the floating piston cavity is provided with a limiting boss along the circumferential direction on the side near the gear.

[0015] In some embodiments, the floating piston assembly further includes a fixed base and a support disk. The support disk includes a chassis and a guide post, and is mounted on the fixed base via the guide post. The floating piston contacts the upper surface of the chassis of the support disk. The fixed base is mounted on one side of the mounting groove of the floating piston assembly, and the floating piston faces the side of the limiting boss.

[0016] In some embodiments, a buffer pad is provided between the floating piston and the limiting boss; a spring is installed on the annular boss of the fixed base, and the guide post is embedded in the coil of the spring.

[0017] Compared with the prior art, the beneficial effects of the present invention include:

[0018] 1. This invention sets up a connected floating piston chamber and a pressure regulating chamber on the pump body, and installs a floating piston assembly and a pressure regulating assembly respectively. High-pressure gas is introduced into the connected chamber. The floating piston moves back and forth under the action of the gas pressure, which can absorb and suppress flow pulsation, so as to realize the smooth pumping of hydraulic oil from the outlet of the gear pump. The gas pressure in the connected chamber is adjusted by the pressure regulating assembly, which is suitable for more different working conditions.

[0019] 2. By installing the floating piston assembly and the air pressure regulating assembly in the floating piston chamber and the air pressure regulating chamber respectively in the pump body, the present invention makes the gear pump compact and eliminates the need for an external connection of a complex flow pulsation suppression device, making it more suitable for occasions with high requirements for hydraulic system volume and flow pulsation.

[0020] 3. The spring in the floating piston assembly of the present invention can provide auxiliary support for the floating piston when the hydraulic pump experiences a large fluctuation impact at the moment of startup, preventing the parts from being damaged by strong impact and extending the service life of the gear pump.

[0021] 4. This invention provides a buffer pad between the floating piston and the boss, which acts as a buffer and vibration absorber, thereby reducing the vibration and noise of the gear pump during operation and extending its service life.

[0022] 5. The internal gear pump provided by the present invention has a piezoelectric element in the air pressure regulating component that can detect the gas pressure in the communicating cavity. The piezoelectric element is connected to an external computing and control component by a wire, which facilitates the detection of the air pressure in the communicating cavity and makes it easy to achieve automated control.

[0023] 6. The internal gear pump provided by the present invention has an air valve installed on the fixed side plate that plays a sealing role when the gear pump is working normally. When the air pressure in the connecting cavity is insufficient, the air valve can be connected to the air pump to quickly replenish the air, making the operation simple and convenient. Attached Figure Description

[0024] Figure 1 This is a cross-sectional view of a low-pulsation internal gear pump with a built-in adjustable air pressure damping device according to the present invention.

[0025] Figure 2 This is a three-dimensional view of the rear structure of the pump body of a low-pulsation internal gear pump with a built-in adjustable air pressure damping device according to the present invention.

[0026] Figure 3 A three-dimensional view of the pump body side structure of a low-pulsation internal gear pump with a built-in adjustable air pressure damping device according to the present invention.

[0027] Figure 4 An exploded view of the air pressure regulating component of a low-pulsation internal gear pump with a built-in adjustable air pressure damping device according to the present invention.

[0028] Figure 5 This is a schematic diagram of a floating piston assembly of a low-pulsation internal gear pump with a built-in adjustable air pressure damping device according to the present invention.

[0029] Figure 6 This is a schematic diagram of the fixed base of a low-pulsation internal gear pump with a built-in adjustable air pressure damping device according to the present invention.

[0030] Figure 7 for Figure 1 Enlarged view of a portion of point A in the middle.

[0031] Figure label:

[0032] 1. Pump body; 101. Floating piston chamber; 102. Air pressure regulating chamber; 103. Countersunk through hole; 104. Connecting hole; 105. Limiting boss; 106. First threaded hole; 107. Floating piston assembly mounting slot; 108. Second threaded hole; 109. Air pressure regulating assembly mounting slot; 2. Fixed base; 201. Annular boss; 202. Third threaded hole; 203. Countersunk groove; 3. Support disc; 4. Floating piston; 5. Fixed side plate; 501. Adjusting screw mounting hole; 502. Third threaded hole; 503. Air valve mounting hole; 504. Wire hole; 6. Air pressure regulating piston; 601. Fixing boss; 602. Cross-shaped mounting groove; 7. Adjusting screw; 8. Adjusting screw head; 801. T-shaped boss; 802. Square connecting boss; 9. Air valve; 10. Piezoelectric piece; 11. First trapezoidal sealing ring; 12. Second trapezoidal sealing ring; 13. Buffer pad; 14. Spring; 15. Sealing gasket; 16. O-ring seal; 17. Shaft; 18. Rear pump cover; 19. Front pump cover; 20. Gear; 21. Gear ring. Detailed Implementation

[0033] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0034] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0035] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed", "equipped", "sleeved / connected", "connected", etc., should be interpreted broadly. For example, "connection" can be a wall-mounted connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0036] Reference Figure 1-7 This embodiment provides a low-pulsation internal gear pump with a built-in adjustable air pressure damping device, including a pump body 1, a shaft 17, and a front pump cover 19 and a rear pump cover 18 connecting the two sides of the pump body 1. The pump body 1 is provided with a gear ring 21 and a gear 20 internally meshing in the gear ring 21. A floating piston chamber 101 is provided at the bottom of the oil pressure chamber of the pump body 1. An air pressure regulating chamber 102 is provided on one side of the floating piston chamber 101. The floating piston chamber 101 is located inside the air pressure regulating chamber 102 along the radial direction. A square connecting hole 104 is provided on the side wall of the air pressure regulating chamber 102 near the floating piston chamber 101, thereby connecting the floating piston chamber 101 and the air pressure regulating chamber 102 to form a connecting cavity.

[0037] A pressure regulating component is installed in the pressure regulating chamber 102, and the pressure regulating component regulates the gas pressure in the pressure regulating chamber.

[0038] A floating piston assembly is installed in the floating piston chamber 101. The communicating chamber is filled with gas. The gas pressure regulating assembly detects the gas pressure in the communicating chamber and adjusts the gas pressure according to the actual working conditions. The floating piston 4 of the floating piston reciprocates under the action of gas pressure to suppress the flow pulsation of hydraulic oil in the oil pressure chamber.

[0039] Specifically, the outer side of the pressure regulating chamber 102 along the radial direction is provided with a pressure regulating component mounting groove 109 for mounting a pressure regulating component. The cross-sectional area of ​​the pressure regulating component mounting groove 109 is larger than the cross-sectional area of ​​the gas regulating chamber. The groove surface of the pressure regulating component mounting groove 109 is provided with a plurality of threaded holes and a countersunk through hole 103 communicating with the floating piston chamber 101. The countersunk through hole 103 is used to fill the communicating chamber with air.

[0040] The air pressure regulating assembly is installed in the air pressure regulating assembly mounting slot 109. The air pressure regulating assembly includes a fixed side plate 5, an air pressure regulating piston 6, a piston position adjusting component consisting of an adjusting screw 7 and an adjusting screw head 8, an air valve 9, a piezoelectric plate 10, a trapezoidal sealing ring, and an O-ring 16. The adjusting screw 7 passes through the adjusting screw 7 mounting hole 501 on the fixed side plate 5 and connects to the adjusting screw head 8 to be installed on the fixed side plate 5. The adjusting screw head 8 includes a T-shaped boss 801 formed by two cylinders of different diameters and a square connecting boss 802 connected to the smaller diameter cylinder of the T-shaped boss 801. The end of the adjusting screw 7 facing the air pressure regulating piston 6 is provided with a T-shaped groove for the T-shaped boss 801 to be inserted into, and the connecting boss is placed in the cross-shaped mounting groove of the air pressure regulating piston 6. The fixed side plate 5 is bolted to the air pressure regulating component mounting groove 109 via the fourth threaded hole 202 on the fixed side plate 5 and the second threaded hole 108 on the air pressure regulating component mounting groove 109. When installed, the air pressure regulating piston 6 is positioned towards the floating piston chamber 101, and the adjusting screw 7 is exposed in the air pressure regulating component mounting groove 109.

[0041] The square connecting hole 104 makes the floating piston chamber 101 and the air pressure regulating chamber 102 interconnected chambers with air pressure communication. Rotating the adjusting screw 7 adjusts the length of the screw 7 passing through the fixed side plate 5, thereby adjusting the position of the air pressure regulating piston 6. The air pressure in the interconnected chamber changes accordingly, thus regulating the air pressure in the interconnected chamber. By adjusting the air pressure in the interconnected chamber, it can be applied to more different working conditions. At the same time, since there is a movable connection between the adjusting screw 7 and the adjusting screw head 8, the adjusting screw 7 rotates around the adjusting screw head 8, but the adjusting screw head 8 does not rotate with it. Therefore, only the longitudinal displacement of the adjusting screw 7 is transmitted, without transmitting rotational motion.

[0042] To enable external detection of pressure information in the connected cavity, in this embodiment, a piezoelectric element 10 is disposed between the cross-shaped mounting groove 602 and the square connecting boss 802. One end of a wire is connected to the piezoelectric element 10 through the cross-shaped mounting groove 602, and the other end is connected to an external computing and control component through a wire hole 504. The piezoelectric element 10 can detect the pressure information of the connected cavity and transmit it to the computing and control component outside the gear pump through the wire, thereby realizing intelligent feedback control of the air pressure in the connected cavity. To fix the relative positions of the piezoelectric element 10, the adjusting screw head 8, and the adjusting screw 7, fixing bosses 601 are provided on both sides of the cross-shaped mounting groove 602.

[0043] In this embodiment, the air pressure regulating assembly further includes an air valve 9. The fixed side plate 5 has an air valve 9 mounting hole 503, and the air valve 9 is mounted to the fixed side plate 5 through the air valve 9 mounting hole 503. The air valve 9 is in a closed state to provide a seal when the hydraulic pump is working normally, and is in an open state to replenish air pressure when inflation is needed.

[0044] To ensure the airtightness of the entire air pressure regulating chamber 102, a first trapezoidal sealing ring 11 is installed in the first trapezoidal groove of the air pressure regulating piston 6. An O-ring sealing ring 16, which plays a sealing role, is placed in the countersunk hole 103.

[0045] Furthermore, the floating piston cavity 101 is provided with a floating piston assembly mounting groove 107, which is located on the side of the floating piston cavity 101 near the outside of the pump body 1. The floating piston cavity 101 is provided with a limiting boss 105 along the circumferential direction on the side near the gear.

[0046] The floating piston assembly is installed in the floating piston assembly mounting groove 107. The floating piston assembly includes a fixed base 2, a support disk 3, a floating piston 4, a second trapezoidal sealing ring 12, a buffer pad 13, a spring 14, and a sealing gasket 15. The support disk 3 includes a base and a guide post, and is installed on the fixed base 2 through the guide post. The floating piston 4 is in contact with the upper surface of the base of the support disk 3. The fixed base 2 is installed in the floating piston assembly mounting groove 107 through a third threaded hole 202 on the fixed base 2 and a first threaded hole 106 on the floating piston assembly. When installed, the floating piston 4 faces the limiting boss 105. Under the action of air pressure and air, the floating piston 4 reciprocates towards the boss in the floating piston cavity 101. The limiting boss 105 restricts the position of the floating piston 4. To prevent interference when the pump body 1 and the rear pump cover 18 are fitted together, a countersunk groove 203 is provided on the fixed base 2, and the fixed base 2 is embedded into the pump body 1.

[0047] To ensure airtightness and reduce vibration and noise during gear pump operation, thus extending the service life of the gear pump, a buffer pad 13 is provided between the floating piston 4 and the limiting boss 105 in this embodiment. A second trapezoidal sealing ring 12 is fixed in the second trapezoidal groove on the floating piston 4. The buffer pad 13 can buffer and absorb vibration when the floating piston 4 contacts the limiting boss 105, thereby reducing vibration and noise during gear pump operation. Simultaneously, under pressure, it will adhere tightly to the inner wall of the floating piston cavity 101, providing a double seal with the second trapezoidal sealing ring 12.

[0048] At the moment the hydraulic pump starts, a large pulsating impact is generated. To prevent damage to the parts from the strong impact, in this embodiment, a spring 14 is installed on the annular boss 201 of the fixed base 2, and the guide post of the support disk 3 is embedded in the coil of the spring 14. This provides auxiliary support for the floating piston 4 when there is a large pulsating impact at the moment the hydraulic pump starts.

[0049] To ensure the airtightness of the entire floating piston chamber 101, a sealing gasket 15 is installed between the floating piston assembly mounting groove 107 and the fixed base 2.

[0050] The above description is merely a preferred embodiment of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial modifications made to the present invention by those skilled in the art within the scope of the technology disclosed in the present invention using this concept shall be deemed as an infringement of the protection scope of the present invention.

Claims

1. A low-pulsation internal gear pump with a built-in adjustable air pressure damping device, comprising a pump body and a front pump cover and a rear pump cover connecting the two sides of the pump body, wherein the pump body is provided with a gear ring and a gear internally meshing within the gear ring, characterized in that, The bottom of the oil pressure chamber of the pump body is provided with a floating piston chamber, and a pressure regulating chamber is provided on one side of the floating piston chamber. The floating piston chamber and the pressure regulating chamber are connected to form a communicating cavity. A pressure regulating component is installed in the pressure regulating chamber, and the pressure regulating component regulates the gas pressure in the pressure regulating chamber. A floating piston assembly is installed inside the floating piston chamber. The chamber is filled with gas. The gas pressure regulating component detects the gas pressure inside the chamber and adjusts the pressure. The floating piston of the floating piston assembly reciprocates under the gas pressure to suppress the flow pulsation of hydraulic oil in the hydraulic oil chamber. The floating piston chamber is located radially inside the gas pressure regulating chamber. A connecting hole is provided on the side wall of the gas pressure regulating chamber closest to the floating piston chamber. A gas valve for installing the gas pressure regulating component is provided radially outside the gas pressure regulating chamber. A pressure regulating component mounting slot is provided, the cross-sectional area of ​​which is larger than that of the pressure regulating cavity; the groove surface of the pressure regulating component mounting slot is provided with a countersunk through hole communicating with the floating piston cavity; the pressure regulating component includes a fixed side plate, a pressure regulating piston, and a piston position adjusting component, the piston position adjusting component passing through the fixed side plate and connected to the pressure regulating piston; the fixed side plate is installed in the pressure regulating component mounting slot, the pressure regulating piston is oriented towards the floating piston cavity, and the piston position adjusting component is exposed in the pressure regulating component mounting slot.

2. The low-pulsation internal gear pump with built-in adjustable air pressure damping device according to claim 1, characterized in that, The pressure regulating piston has a mounting groove on the side facing the fixed side plate. The piezoelectric sheet is mounted in the mounting groove. One end of the wire is connected to the piezoelectric sheet through the mounting groove, and the other end is connected to an external computing and control component to detect the pressure in the communicating cavity.

3. The low-pulsation internal gear pump with built-in adjustable air pressure damping device according to claim 1, characterized in that, The piston position adjustment component includes an adjustment screw and an adjustment screw head. The adjustment screw is installed on the fixed side plate through an adjustment screw mounting hole on the fixed side plate. The adjustment screw head includes a T-shaped boss formed by connecting two cylinders of different diameters and a connecting boss connected to the smaller diameter cylinder of the T-shaped boss. The end of the adjusting screw facing the air pressure regulating piston is provided with a T-shaped groove for the T-shaped boss to be inserted, and the connecting boss is connected to the air pressure regulating piston.

4. The low-pulsation internal gear pump with built-in adjustable air pressure damping device according to claim 1, characterized in that, The air pressure regulating assembly also includes an air valve, and an air valve mounting hole is provided on the fixed side plate, through which the air valve is mounted on the fixed side plate.

5. The low-pulsation internal gear pump with built-in adjustable air pressure damping device according to claim 1, characterized in that, The floating piston cavity is provided with a floating piston assembly mounting groove, which is located on the side of the floating piston cavity near the outside of the pump body. The floating piston cavity is provided with a limiting boss along the circumferential direction on the side near the gear.

6. The low-pulsation internal gear pump with built-in adjustable air pressure damping device according to claim 5, characterized in that, The floating piston assembly further includes a fixed base and a support disk. The support disk includes a chassis and a guide post, and is mounted on the fixed base via the guide post. The floating piston is in contact with the upper surface of the chassis of the support disk. The fixed base is mounted on one side of the mounting groove of the floating piston assembly, and the floating piston faces the side of the limiting boss.

7. The low-pulsation internal gear pump with built-in adjustable air pressure damping device according to claim 6, characterized in that, A buffer pad is provided between the floating piston and the limiting boss; a spring is installed on the annular boss of the fixed base, and the guide post is embedded in the coil of the spring.

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