A pressure measuring tool for adapting a static pressure oil cylinder

Abstract

The utility model discloses a kind of pressure measuring tool suitable for static pressure oil cylinder, including static pressure oil cylinder;Static pressure oil cylinder is constituted by cylinder barrel, piston rod and guide sleeve;Four throttle holes of circumferential array are opened on the outer surface of guide sleeve;Throttle hole inside is equipped with throttle valve;The pressure measuring tool suitable for the guide sleeve of static pressure oil cylinder;Pressure measuring tool includes pressure measuring shaft rod;Four deep holes of circumferential array are opened in pressure measuring shaft rod one end.Deep hole on pressure measuring shaft rod is used, pressure measuring sensor is installed in deep hole, detects pressure measuring area oil pressure, uses throttle valve to adjust throttle hole diameter, reaches oil pressure balance, until piston rod is suspended in cylinder barrel middle, wherein, pressure measuring shaft rod can be removed, adjust next oil cylinder, avoid the complex structure that traditional oil cylinder is fixedly arranged in each guide sleeve inside guide hole, oil supply pipeline and pressure measuring element, simplify the structure of static pressure oil cylinder guide sleeve, reduce its outer diameter size and overall weight, save material cost.

Description

Technical Field

[0001] This utility model belongs to the field of hydraulic cylinder technology, specifically, it relates to a pressure measuring tool adapted to a hydrostatic cylinder. Background Technology

[0002] Hydraulic cylinders are the core actuators in hydraulic systems, essentially energy conversion devices that transform hydraulic energy into linear reciprocating mechanical energy. They mainly consist of a cylinder barrel, piston, piston rod, guide sleeve, and seals. Their working principle relies on pressurized hydraulic fluid entering the cylinder chamber, pushing the piston, which in turn drives the piston rod to extend or retract, generating a powerful pushing or pulling force. However, in traditional hydraulic cylinders, direct sliding friction exists between the piston rod and guide sleeve, and between the piston and cylinder barrel. This not only causes creeping and continuous wear under low-speed, heavy-load conditions, but also leads to stress concentration under eccentric or lateral loads, exacerbating wear and even causing seizure or scoring, ultimately resulting in a significant decrease in positioning accuracy and rigidity.

[0003] In existing technologies, researchers utilize the principles of hydrostatics to continuously inject high-pressure oil into the gap between the piston rod and the guide sleeve, forming a rigid oil film that can "float" the components. This completely eliminates direct contact and sliding friction between metals, solving the problems of crawling, wear, and seizing caused by lateral forces in traditional hydraulic cylinders under low-speed, heavy-load conditions.

[0004] During this process, because the hydrostatic support guide sleeve of the hydraulic cylinder adopts a circumferential hydrostatic measurement method, it is necessary to set up complex structures such as guide holes, oil supply pipes and pressure measuring elements on each guide sleeve (e.g., Figure 9 As shown, the static pressure effect is ensured by adjusting the orifice diameter. However, the orifice diameter adjustment is only required at the factory. This design not only fails to function during the use of the cylinder, but also increases the outer diameter and overall weight of the guide sleeve, which leads to a significant increase in manufacturing costs and energy consumption. Furthermore, the addition of an oil supply device introduces additional leakage points and failure risks, reducing the static pressure support performance and reliability of the guide sleeve, thus having certain limitations. Utility Model Content

[0005] To address the technical problem that in existing hydrostatic support structures, each guide sleeve requires an oil supply pipe, a guide hole, and a pressure measuring element, which increases its outer diameter and weight, thereby raising manufacturing costs and energy consumption, this invention provides a pressure measuring fixture adapted to hydrostatic cylinders.

[0006] The objective of this utility model can be achieved through the following technical solutions: A pressure testing fixture adapted to a hydrostatic cylinder includes a hydrostatic cylinder; the hydrostatic cylinder consists of a cylinder barrel, a piston rod, and a guide sleeve; the pressure testing fixture is detachably inserted into the guide sleeve; the guide sleeve has a T-shaped cross-section; four throttling orifices in a circumferential array are opened on the outer surface of the guide sleeve; each throttling orifice is equipped with a throttling valve; the pressure testing fixture is adapted to the guide sleeve of the hydrostatic cylinder; the pressure testing fixture includes a pressure testing shaft; one end of the pressure testing shaft has four deep holes in a circumferential array; the pressure testing shaft has a connecting hole corresponding to the position of the throttling orifice, and the connecting hole, the deep hole, and the throttling orifice are connected.

[0007] Furthermore, the hollow inner wall of the guide sleeve is provided with four pressure measuring zones corresponding to the positions of the throttling orifice; the pressure measuring shaft is inserted into the guide sleeve so that the pressure measuring sensor connected to the deep hole of the pressure measuring shaft is connected to the pressure measuring zone, and the throttling valve adjusts the size of the throttling orifice to stabilize the oil pressure between the guide sleeve and the piston rod.

[0008] Furthermore, the cylinder is mounted on two guide sleeves; the piston rod is inserted inside the two guide sleeves.

[0009] Furthermore, two symmetrical working oil ports are provided on the outer surface of the cylinder.

[0010] Furthermore, two symmetrical oil supply ports are provided on one side of the outer surface of the cylinder, and these oil supply ports are connected to the throttling holes on the guide sleeve.

[0011] Furthermore, an annular oil cavity is formed between the guide sleeve and the piston rod.

[0012] Furthermore, hydraulic oil is introduced into the throttle orifice at the oil supply port, and the pressure measuring shaft is inserted into the guide sleeve so that the pressure measuring sensor connected to the deep hole of the pressure measuring shaft is connected to the pressure measuring area. The throttle valve adjusts the size of the throttle orifice to stabilize the oil pressure between the guide sleeve and the piston rod. The pressure measuring shaft is removed, and one of the guide sleeves is removed to install the piston rod. The removed guide sleeves are assembled to form a hydrostatic cylinder.

[0013] The beneficial effects of this utility model are: 1. This utility model features a pressure measuring fixture that is movably installed inside the hydraulic cylinder guide sleeve. A pressure measuring connector and a pressure sensor are installed inside a deep hole on the pressure measuring shaft. By detecting the oil pressure in the pressure measuring area of ​​the guide sleeve, and then adjusting the throttle orifice size using a throttle valve, the oil pressure is balanced until the piston rod can be suspended in the center of the cylinder, completing the static pressure adjustment of the hydraulic cylinder. The pressure measuring shaft can be removed to continue adjusting the next hydraulic cylinder. This avoids the complex structure required by traditional hydraulic cylinder pressure adjustment methods, which necessitates fixing guide holes, oil supply pipes, and pressure measuring elements inside each guide sleeve. It significantly simplifies the construction of the static pressure hydraulic cylinder guide sleeve, reduces its outer diameter and overall weight, saves material costs, and optimizes the adjustment accuracy, reliability, and ease of maintenance of the hydraulic cylinder.

[0014] 2. This utility model has a pressure measuring area on the hollow inner wall of the guide sleeve. This pressure measuring area cooperates with a pressure measuring shaft that is movably set inside the guide sleeve. The pressure measuring shaft has a deep hole to accommodate the pressure measuring connector and the pressure measuring sensor, thereby detecting the oil pressure in the pressure measuring area of ​​the guide sleeve in real time. The pressure data is collected and transmitted to the external control system in real time. Then, the throttle valve is operated to adjust the orifice diameter until a stable oil pressure is achieved. The pressure measuring area is clearly marked, which is convenient and quick, and improves the practicality. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the fit between the pressure measuring tool and the guide sleeve in this utility model; Figure 2 This is a cross-sectional view of the pressure measuring tool and the guide sleeve in this utility model. Figure 3 This is a schematic diagram of the hydrostatic cylinder of this utility model; Figure 4 for Figure 3 Radial cross-sectional view; Figure 5 This is a front view of the hydrostatic cylinder in this utility model; Figure 6 for Figure 5 Cross-sectional view at point AA; Figure 7 This is a schematic diagram of the guide sleeve in this utility model; Figure 8 This is a cross-sectional schematic diagram of the guide sleeve in this utility model; Figure 9 Existing technical drawings for guide sleeves; The attached diagram lists the components represented by each number as follows: 1. Cylinder; 2. Piston rod; 3. Guide sleeve; 31. Throttling orifice; 32. Throttling valve; 33. Hollow inner wall; 34. Pressure measuring zone; 4. Oil supply port; 5. Working oil port; 6. Oil chamber; 7. Pressure measuring shaft; 71. Deep hole; 72. Connecting hole. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] Please see Figure 1 - Figure 2 , Figures 6-8As shown, a pressure measuring fixture adapted to a hydrostatic cylinder includes a pressure measuring shaft 7; one end of the pressure measuring shaft 7 has four deep holes 71 arranged in a circumferential array for installing a pressure measuring connector (not shown in the figure), which is used to connect a pressure sensor; the pressure measuring shaft 7 is detachably disposed inside a guide sleeve 3, the guide sleeve 3 having a T-shaped cross-section; four throttling holes 31 arranged in a circumferential array are formed on the outer surface of one end of the guide sleeve 3; the pressure measuring shaft 7 has a connecting hole 72 corresponding to the position of the throttling holes 31. The connecting hole 72 is connected to the deep hole 71 or the throttling hole 31; the hollow inner wall 33 of the guide sleeve 3 is provided with four pressure measuring areas 34 corresponding to the position of the throttling hole 31; each throttling hole 31 is equipped with a throttling valve 32, which is used to adjust the size of the throttling hole 31; the pressure sensor connected to the pressure measuring shaft 7 can detect the oil pressure in the pressure measuring area 34 on the hollow inner wall 33 of the guide sleeve 3, and then adjust the size of the throttling hole 31 using the throttling valve 32 according to the tested oil pressure until the oil pressure is stable.

[0018] Please see Figures 3-6 As shown, a cylinder 1 is mounted on both guide sleeves 3, with one end of the guide sleeve 3 inserted into the cylinder 1 and the other end fitting against the cylinder 1 to seal it and ensure its airtightness. A piston rod 2 is inserted into both guide sleeves 3, and the diameter of the piston rod 2 is the same as the diameter of the pressure measuring shaft 7. Two symmetrical working oil ports 5 are provided on the outer surface of the cylinder 1, which are used to assist the left and right movement of the piston rod 2. Two symmetrical oil supply ports 4 are provided on one side of the outer surface of the cylinder 1. It is connected to the throttle hole 31 on the guide sleeve 3; the guide sleeve 3 and the piston rod 2 form an annular oil chamber 6; the oil supply port 4 is used to pressurize the inside of the throttle hole 31, and the pressure measuring shaft 7 is used to detect the pressure in the measuring area 34. The size of the throttle hole 31 is adjusted by the throttle valve 32 to ensure that the pressure in the oil chamber 6 is equal. Then the pressure measuring shaft 7 is removed, one of the guide sleeves 3 is removed, the piston rod 2 is installed, and the removed guide sleeve 3 is assembled. It can be achieved that the piston rod 2 is suspended in the middle of the cylinder 1 without contact with metal when no external force is applied.

[0019] In practical use, the operator first assembles the two guide sleeves 3, each with a four-circular array of throttling orifices 31, with the cylinder 1 (note the connection between the oil supply port 4 and the throttling orifice 31). Next, a pressure measuring shaft 7 with a pressure sensor already installed is installed in the hollow part of the two guide sleeves 3. The pressure measuring shaft 7 is used to measure the pressure of the guide sleeves 3 at both ends of the cylinder 1. The pressure is then adjusted using the throttle valve 32 installed in the throttling orifice 31 until the pressure in the cavity between the hollow inner wall 33 of the guide sleeve 3 and the pressure measuring shaft 7 stabilizes. Then, the pressure measuring shaft 7 and one of the guide sleeves 3 are removed. The piston rod 2 is then installed at the location where the pressure measuring shaft 7 was previously installed. Finally, the removed guide sleeve 3 is reinstalled. At this point, the piston rod 2 is suspended in the center of the cylinder 1, not in contact with metal, completing the overall assembly and adjustment of the hydraulic cylinder. The removed pressure measuring shaft 7 can be reused in subsequent hydraulic cylinder assembly and adjustment.

[0020] This invention features a movable pressure-measuring shaft 7 inside the guide sleeve 3. A deep hole 71 is formed on the pressure-measuring shaft 7, and a pressure-measuring connector and a pressure sensor are installed inside the deep hole 71. By detecting the oil pressure in the pressure-measuring zone 34 of the guide sleeve 3 and adjusting the diameter of the throttle orifice 31 using the throttle valve 32, oil pressure balance is achieved until the piston rod 2 can be suspended in the center of the cylinder 1, completing the adjustment of the hydraulic cylinder. The pressure-measuring shaft 7 is detachable, allowing it to be removed after the current hydraulic cylinder adjustment is completed and then used for the adjustment of the next hydraulic cylinder. This avoids the complex structure of traditional hydraulic cylinder pressure adjustment methods, which require fixed guide holes, oil supply pipes, and pressure-measuring elements inside each guide sleeve 3. It significantly simplifies the overall structure of the guide sleeve 3, reduces its outer diameter and overall weight, saves material costs, and optimizes the adjustment accuracy, reliability, and ease of maintenance of the hydraulic cylinder.

[0021] This invention features a pressure measuring area 34 on the hollow inner wall 33 of the guide sleeve 3, which cooperates with a pressure measuring shaft 7 movably disposed inside the guide sleeve 3. The pressure measuring shaft 7 has a deep hole 71 to accommodate a pressure measuring connector and a pressure sensor, thereby enabling real-time monitoring of the oil pressure in the pressure measuring area 34 of the guide sleeve 3. The detected pressure data is instantly collected and transmitted to an external control system. The orifice diameter of the throttle valve 32 is adjusted until the oil pressure reaches a stable state. The pressure measuring area 34 is clearly marked, making detection and adjustment operations convenient and quick, thus improving the practicality of the structure.

[0022] It should be noted that, in this document, terms such as “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0023] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention.

Claims

1. A pressure measuring fixture adapted to a hydrostatic cylinder, comprising a hydrostatic cylinder; the hydrostatic cylinder is composed of a cylinder barrel (1), a piston rod (2), and a guide sleeve (3); characterized in that: The pressure testing fixture is detachably inserted into the guide sleeve (3); the cross-section of the guide sleeve (3) is T-shaped; four throttling holes (31) in a circular array are opened on the outer surface of the guide sleeve (3); each throttling hole (31) is equipped with a throttling valve (32). The pressure measuring fixture is adapted to the guide sleeve (3) of the hydrostatic cylinder; the pressure measuring fixture includes a pressure measuring shaft (7); one end of the pressure measuring shaft (7) is provided with four deep holes (71) in a circumferential array; the pressure measuring shaft (7) is provided with a connecting hole (72) corresponding to the position of the throttle hole (31), and the connecting hole (72), the deep hole (71) and the throttle hole (31) are connected.

2. The pressure measuring fixture adapted to a hydrostatic cylinder according to claim 1, characterized in that: The hollow inner wall (33) of the guide sleeve (3) is provided with four pressure measuring zones (34) corresponding to the position of the throttling orifice (31). Insert the pressure measuring shaft (7) into the guide sleeve (3) so that the pressure measuring sensor connected to the deep hole (71) of the pressure measuring shaft (7) is connected to the pressure measuring area (34). Adjust the size of the throttle orifice (31) of the throttle valve (32) to stabilize the oil pressure between the guide sleeve (3) and the piston rod (2).

3. The pressure measuring fixture adapted to a hydrostatic cylinder according to claim 1, characterized in that: The cylinder (1) is mounted on two guide sleeves (3); the piston rod (2) is inserted inside the two guide sleeves (3).

4. The pressure measuring fixture adapted to a hydrostatic cylinder according to claim 1, characterized in that: Two symmetrical working oil ports (5) are provided on the outer surface of the cylinder (1).

5. The pressure measuring fixture adapted to a hydrostatic cylinder according to claim 1, characterized in that: The cylinder (1) has two symmetrical oil inlets (4) on one side of its outer surface. The oil inlets (4) are connected to the throttle hole (31) on the guide sleeve (3).

6. The pressure measuring fixture adapted to a hydrostatic cylinder according to claim 1, characterized in that: The guide sleeve (3) and the piston rod (2) form an annular oil cavity (6).

7. A pressure measuring fixture adapted to a hydrostatic cylinder according to claim 5, characterized in that: Hydraulic oil is introduced into the throttle hole (31) at the oil supply port (4). The pressure measuring shaft (7) is inserted into the guide sleeve (3) so that the pressure measuring sensor connected to the deep hole (71) of the pressure measuring shaft (7) is connected to the pressure measuring area (34). The throttle valve (32) adjusts the size of the throttle hole (31) to stabilize the oil pressure between the guide sleeve (3) and the piston rod (2). The pressure measuring shaft (7) is removed, and one of the guide sleeves (3) is removed to install the piston rod (2). The removed guide sleeves (3) are assembled to form a hydrostatic cylinder.

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