Rotary hydraulic actuator with inner limiting gear and rack

Abstract

The utility model relates to a rotary hydraulic actuator with an inner limiting gear rack, which comprises a box body and an inner limiting gear rack component, the inner limiting gear rack component comprises a piston which is arranged in the box body along the axial direction, a rack is arranged on the piston, and two ends of the piston are arranged in the box body through piston support rings; the gear shaft is arranged in the box body in the longitudinal direction and is meshed with the rack of the piston; the limiting cam is mounted on the gear shaft; stroke adjustment of the actuator is achieved in a built-in limiting cam mode, the risk of hydraulic oil leakage is effectively avoided, the rack is designed to be provided with the double glyd rings and the supporting rings, the motion stability of a product is improved, the service life of the product is prolonged, the box body is additionally provided with the pressure relief valve, and when hydraulic oil in the actuator leaks, the pressure relief valve is closed. And when the pressure in the box body rises, the pressure can be released through the pressure release valve, so that the use safety of the product is improved.

Description

Technical Field

[0001] The utility model discloses a rotary hydraulic actuator with an inner-limiting gear rack, belongs to the technical field, and specifically relates to a rotary hydraulic actuator with an inner-limiting gear rack. Background Art

[0002] Hydraulic actuators are widely used in the shipbuilding industry. Hydraulic actuators can be modularized, can be used in combination with other modules, and can be remotely / locally operated. They have compact structures, small volumes, and stable and reliable movements. They are a commonly used control method in the shipbuilding industry's automated control systems.

[0003] At present, the commonly used hydraulic actuators on the market mainly include rack and pinion hydraulic actuators and spiral hydraulic actuators. Since rack and pinion hydraulic actuators are easy to process and manufacture, rack and pinion actuators are more widely used. Conventional rack and pinion hydraulic actuators are mainly driven by hydraulic oil to make linear motion of the rack piston, and the rack piston drives the gear shaft to make rotary motion, thereby driving the valve to open and close. When the valve action is not in place, the actuator stroke needs to be adjusted. Conventional rack and pinion hydraulic actuators use cylinder covers on both sides plus limit screws and nuts to limit the actuator stroke. When adjusting the stroke, you need to loosen the locking nut first, then adjust the limit screw to the appropriate position, and then tighten the locking nut after adjusting it in place.

[0004] Existing rack and pinion hydraulic actuators generally use cylinder covers on both sides with limit screws and nuts to limit the actuator's stroke. In this way, when the actuator needs to adjust its stroke, the hydraulic oil inside the cylinder is prone to leak from the cylinder cover during the adjustment of the limit screws, and the adjustment accuracy is low, which affects the normal operation of the actuator, increases the risk of valve failure, and increases the manufacturer's after-sales cost. Utility Model Content

[0005] Purpose of the utility model: to provide a rotary hydraulic actuator with an internal limit gear rack, to solve the above-mentioned problem that when the actuator needs to adjust the stroke, during the adjustment of the limit screw, the hydraulic oil inside the cylinder body is prone to leak from the cylinder head, and the adjustment accuracy is low, thereby affecting the normal operation of the actuator, increasing the risk of valve failure, and increasing the manufacturer's after-sales cost.

[0006] Technical solution: Aiming at the failure point that leakage is easy to occur during the stroke adjustment of the existing gear rack rotary hydraulic actuator, a gear rack rotary hydraulic actuator with internal limit is proposed, the hydraulic actuator comprises: a box body, the interior of the box body is in a cavity shape and is provided with four outlets at the upper, lower, left and right sides; an internal limit gear rack assembly, which is arranged in the box body;

[0007] The inner limit gear rack assembly includes: a piston, which is arranged in the housing along the axial direction, and a rack is provided on the piston. Both ends of the piston are installed in the housing through piston support rings; a gear shaft, which is arranged in the housing along the longitudinal direction and meshes with the rack of the piston; and a limit cam, which is installed on the gear shaft.

[0008] In a further embodiment, square sealing rings are provided on both sides of the piston support ring, one square sealing ring is installed between the piston and the piston support ring, and the other square sealing ring is installed between the piston support ring and the outlet of the casing.

[0009] In a further embodiment, an upper shaft bearing is installed at the end of the gear shaft and a lower shaft bearing is installed at the tail. The upper shaft bearing is installed in the box body through an upper shaft support ring, and the lower shaft bearing is installed in the box body through a lower shaft support ring. An upper shaft O-ring is provided between the upper shaft support ring and the upper outlet of the box body, and a lower shaft O-ring is provided between the lower shaft support ring and the lower outlet of the box body.

[0010] In a further embodiment, a top cover fixedly connected by top cover screws is installed on the upper outlet of the box body, a dial is provided on the top cover, an indicator fixedly connected by indicator screws is provided in the dial, and a top cover O-ring is provided between the top cover and the upper outlet of the box body.

[0011] In a further embodiment, a cylinder cover fixedly connected by cylinder cover screws is installed on both the left outlet and the right outlet of the box body, and a cylinder cover O-ring is provided between the cylinder cover and the left outlet of the box body.

[0012] In a further embodiment, a pressure relief valve, a limit screw and a limit nut are provided at the front of the box body, the pressure relief valve is installed at the front of the box body, the limit screws are installed at the front of the box body through the limit nuts and are located on both sides of the pressure relief valve, and the limit screws extend through the box body to the interior.

[0013] In a further embodiment, a side cover plate fixedly connected by side cover plate screws is installed at the rear of the box body, and a side cover plate O-ring is provided between the side cover plate and the rear of the box body.

[0014] In a further embodiment, the box body is provided with a hydraulic ball expansion plug and a box body O-ring.

[0015] Beneficial effects: The utility model optimizes the traditional limiting method based on the traditional hydraulic actuator, cancels the original external limiting method at both ends of the end cover, and adopts the internal limiting cam method for limiting. After the optimized design, the limiting cam is installed inside the box body and cooperates with the gear shaft. The hydraulic oil drives the rack piston to make a linear motion, and the rack drives the gear shaft and the limiting cam to make a rotational motion together. When the valve needs to be adjusted in stroke, first loosen the locking nut, then adjust the limiting screw, and finally fix the locking nut when it is adjusted to the appropriate position. During the entire stroke adjustment process, the limiting screw and the hydraulic oil are not in contact throughout the whole process, avoiding the risk of hydraulic oil leakage. The use of the internal limiting cam method greatly reduces the risk of hydraulic oil leakage, reduces the overall maintenance cycle, improves the limiting accuracy, and makes the stroke adjustment more convenient and reliable. In addition, a safety pressure relief valve is added to the box body to improve the safety of product use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the utility model.

[0017] Figure numerals: indicator screw 1, indicator 2, dial 3, top cover screw 4, top cover 5, top cover O-ring 6, side cover screw 7, side cover 8, side cover O-ring 9, hydraulic ball expansion plug 10, box O-ring 11, cylinder head screw 12, cylinder head 13, cylinder head O-ring 14, square seal 15, piston support ring 16, rack 17, box 18, pressure relief valve 19, limit nut 20, limit screw 21, upper shaft O-ring 22, upper shaft support ring 23, upper shaft bearing 24, limit cam 25, gear shaft 26, lower shaft bearing 27, lower shaft support ring 28, lower shaft O-ring 29. DETAILED DESCRIPTION

[0018] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0020] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed 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 it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. In addition, the technical features involved in the different embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0021] A rotary hydraulic actuator with an internally limited gear rack, the hydraulic actuator comprising: a box body 18, the interior of the box body 18 is in a cavity shape and is provided with four outlets, namely, upper, lower, left and right; an internally limited gear rack assembly, which is arranged in the box body;

[0022] The inner limit gear rack assembly includes: a piston, which is arranged in the box body 18 along the axial direction, and a rack 17 is formed on the piston. Both ends of the piston are installed in the box body 18 through piston support rings 16; a gear shaft 26, which is arranged in the box body 18 along the longitudinal direction and meshes with the rack 17 of the piston; and a limit cam 25, which is installed on the gear shaft 26.

[0023] In one embodiment, Figure 1 As shown, square sealing rings 15 are provided on both sides of the piston support ring 16 , one square sealing ring 15 is installed between the piston and the piston support ring 16 , and the other square sealing ring 15 is installed between the piston support ring 16 and the outlet in the box body 18 .

[0024] In one embodiment, Figure 1 As shown, the end of the gear shaft 26 is installed with an upper shaft bearing 24 and the tail is installed with a lower shaft bearing 27. The upper shaft bearing 24 is installed in the box 18 through an upper shaft support ring 23, and the lower shaft bearing 27 is installed in the box 18 through a lower shaft support ring 28. An upper shaft O-ring 22 is provided between the upper shaft support ring 23 and the upper outlet of the box 18, and a lower shaft O-ring 29 is provided between the lower shaft support ring 27 and the lower outlet of the box 18.

[0025] In one embodiment, Figure 1 As shown, a top cover 5 fixedly connected by a top cover screw 4 is installed on the upper outlet of the box body 18, a dial 6 is provided on the top cover 5, an indicator 2 fixedly connected by an indicator screw 1 is provided inside the dial 6, and a top cover O-ring 6 is provided between the top cover 5 and the upper outlet of the box body 19=8.

[0026] In one embodiment, Figure 1 As shown, a cylinder head 13 fixedly connected by a cylinder head screw 12 is installed on the left outlet and the right outlet of the box body 18, and a cylinder head O-ring 14 is provided between the cylinder head 13 and the left outlet of the box body 18.

[0027] In one embodiment, Figure 1 As shown, a pressure relief valve 19, a limit screw 21 and a limit nut 22 are provided at the front of the box body 18. The pressure relief valve 19 is installed at the front of the box body. The limit screw 21 is installed at the front of the box body 18 through the limit nut 22 and is located on both sides of the pressure relief valve 19. The limit screw 21 passes through the box body 18 and extends to the interior.

[0028] In one embodiment, Figure 1 As shown, a side cover plate 8 fixedly connected by side cover plate screws 7 is installed at the rear of the box body 18, and a side cover plate O-ring 9 is provided between the side cover plate 8 and the rear of the box body 18.

[0029] In one embodiment, Figure 1 As shown, the box body is provided with a hydraulic ball expansion plug 10 and a box body O-ring 11.

[0030] In one embodiment, Figure 1 As shown, the box body 18 adopts a QT450 integral casting structure, which is simple in structure and easy to process.

[0031] The rack 17, the cylinder head 13, the top cover 5, and the limit cam 25 are all made of 45 steel and are surface treated to improve the overall performance.

[0032] The gear shaft 26 adopts an integrated design of 16 teeth alloy steel to improve transmission accuracy, and the connection size at the bottom of the gear shaft conforms to the ISO5211 connection standard.

[0033] The limit cam 25 adopts an inner octagonal arc design to increase the contact area and reduce stress concentration.

[0034] The top installation dimensions of the top cover 5 and the top connection dimensions of the gear shaft comply with the BS EN15714-4 connection standard.

[0035] The cylinder head 13 and the housing 18 as well as the limit screws 21 and the housing 18 are connected and fixed by 8.8 grade high-strength screws to ensure the overall connection strength.

[0036] The rack 17 adopts a double Gly ring plus a support ring design to ensure sealing performance.

[0037] Bearings 27 and 24 are added to the bottom of the gear shaft 26 and the top of the limit cam to avoid friction between the gear shaft and the box body when the gear shaft moves, thereby improving the movement stability.

[0038] The top of the hydraulic actuator adopts a dial with scale display 3 and indicator 2, which is convenient for on-site operators to identify and install and debug.

[0039] Working principle: Hydraulic oil enters the left cavity of the hydraulic actuator. Figure 1 As shown, at this time, the hydraulic oil pushes the rack to the right for linear motion, the rack meshes with the gear shaft, and the gear shaft drives the valve stem to rotate clockwise. The gear shaft rotates 90 degrees clockwise (adjustable by ±5 degrees), and the hydraulic oil in the right cavity of the hydraulic actuator returns to the oil tank through the hydraulic oil port of the actuator, completing a one-way action to achieve the valve closing action. When the hydraulic oil enters the right cavity as shown in the figure, the hydraulic oil in the right cavity is returned to the oil tank through the hydraulic oil port of the actuator. Figure 1 As shown, the hydraulic oil pushes the rack to the left to make a linear motion, and the gear shaft drives the valve stem to make a counterclockwise rotation motion. The gear shaft rotates counterclockwise 90 degrees (adjustable by ±5 degrees), and the hydraulic oil in the left cavity of the hydraulic actuator returns to the oil tank through the hydraulic port of the actuator, completing a one-way action to realize the valve opening action. When the valve switch action is not in place and the stroke needs to be adjusted, the stroke can be adjusted by adjusting the limit screw 21. Figure 1 As shown, the left limit screw adjusts the valve opening position, and the right limit screw adjusts the valve closing position. For standard products, the stroke can achieve ±5 degree position adjustment, that is, -5 degrees to +95 degrees. Special strokes can be achieved by customizing the limit cam 25.

[0040] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.

Claims

1. A rotary hydraulic actuator with internal limit gear rack, characterized in that: The hydraulic actuator comprises: a box body, the interior of the box body is in a cavity shape and is provided with four outlets, namely, upper, lower, left and right; an internal limit gear rack assembly, which is arranged in the box body; The inner limit gear rack assembly includes: a piston, which is arranged in the housing along the axial direction, and a rack is provided on the piston. Both ends of the piston are installed in the housing through piston support rings; a gear shaft, which is arranged in the housing along the longitudinal direction and meshes with the rack of the piston; and a limit cam, which is installed on the gear shaft.

2. According to claim 1, a rotary hydraulic actuator with internal limit gear rack, characterized in that: Square sealing rings are provided on both sides of the piston support ring, one square sealing ring is installed between the piston and the piston support ring, and the other square sealing ring is installed between the piston support ring and the outlet of the box body.

3. According to claim 1, a rotary hydraulic actuator with internal limit gear rack, characterized in that: An upper shaft bearing is installed at the end of the gear shaft, and a lower shaft bearing is installed at the tail. The upper shaft bearing is installed in the box body through an upper shaft support ring, and the lower shaft bearing is installed in the box body through a lower shaft support ring. An upper shaft O-shaped sealing ring is provided between the upper shaft support ring and the upper outlet of the box body, and a lower shaft O-shaped sealing ring is provided between the lower shaft support ring and the lower outlet of the box body.

4. According to claim 1, a rotary hydraulic actuator with internal limit gear rack, characterized in that: A top cover fixedly connected by top cover screws is installed on the upper outlet of the box body, a dial is arranged on the top cover, an indicator fixedly connected by indicator screws is arranged inside the dial, and a top cover O-shaped sealing ring is arranged between the top cover and the upper outlet of the box body.

5. According to claim 1, a rotary hydraulic actuator with internal limit gear rack, characterized in that: The left outlet and the right outlet of the box body are both equipped with cylinder covers fixedly connected by cylinder cover screws, and a cylinder cover O-shaped sealing ring is arranged between the cylinder cover and the left outlet of the box body.

6. The rotary hydraulic actuator with internally limited gear rack according to claim 1, characterized in that: A pressure relief valve, a limit screw and a limit nut are provided at the front of the box body. The pressure relief valve is installed at the front of the box body. The limit screws are installed at the front of the box body through the limit nuts and are located on both sides of the pressure relief valve. The limit screws extend through the box body to the interior.

7. The rotary hydraulic actuator with internally limited gear rack according to claim 1, characterized in that: The rear part of the box body is provided with a side cover plate fixedly connected by side cover plate screws, and a side cover plate O-shaped sealing ring is arranged between the side cover plate and the rear part of the box body.

8. The rotary hydraulic actuator with internally limited gear rack according to claim 1, characterized in that: The box body is provided with a hydraulic ball expansion plug and a box body O-shaped sealing ring.

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