Compact underwater electric cylinder

Abstract

The invention relates to an electric cylinder, in particular to a compact underwater electric cylinder. Comprising an execution assembly, a driving assembly and a transmission assembly, the execution assembly comprises a push rod and a lead screw, the driving assembly comprises a motor, and further comprises a main cylinder body and an end cover, a motor cavity and an execution cavity are formed in one end of the main cylinder body, the driving assembly is located in the motor cavity, and the execution assembly is located in the execution cavity; the rotating shaft of the motor is parallel to the axis of the motor chamber and deviates towards the direction of the execution chamber; and the end cover can seal the ports of the motor chamber and the execution chamber. According to the scheme, the compact underwater electric cylinder is compact in size and has excellent replaceability for an oil cylinder; and the device is light and small and can be used in a certain water area.

Description

Technical Field

[0001] The invention relates to an electric cylinder, in particular to a compact underwater electric cylinder. Background Art

[0002] There are three main types of components that can achieve linear transmission: hydraulic cylinders, pneumatic cylinders, and electric cylinders. Hydraulic cylinders and pneumatic cylinders are both traditional fluid-driven linear transmission components. Compared with traditional linear transmission components, electric cylinders can easily achieve precise control of thrust, speed, and position, and have high cleanliness, which is in line with the current trend of full electrification of construction machinery. However, compared with hydraulic cylinders, electric cylinders will have additional transmission structures such as motors, reducers, and bearing seats, and their mounting bases will also be greatly increased, occupying space inside the electric cylinder. As a result, for the same driving force, the structural dimensions of the electric cylinder are much larger than those of the hydraulic cylinder, resulting in the inability to directly use electric cylinders to directly replace hydraulic cylinders in most situations with strict space restrictions.

[0003] The cylinder body, gear box body, bearing seat and other shell parts of traditional electric cylinders are generally independent of each other or partially integrated into an integral part. This design is convenient for mechanical processing, ensuring the dimensional accuracy of parts and convenient for disassembly and assembly. However, for underwater environments, too many parts will increase the number of matching parts, increase the difficulty of sealing the inner cavity of the electric cylinder and the risk of water leakage. Summary of the invention

[0004] The present invention aims to provide a compact underwater electric cylinder which is suitable for underwater operations and can directly replace a hydraulic cylinder.

[0005] The compact underwater electric cylinder in this scheme includes an actuator assembly, a drive assembly and a transmission assembly. The actuator assembly includes a push rod and a screw rod, and the drive assembly includes a motor. It also includes a main cylinder body and an end cover. One end of the main cylinder body is provided with a motor chamber and an actuator chamber, and the motor chamber and the actuator chamber are both arranged along the axial direction of the main cylinder body. The drive assembly is located in the motor chamber, and the actuator assembly is located in the actuator chamber. This structure is designed for underwater environments and can reduce parts and mating parts, thereby reducing the difficulty of sealing the inner cavity of the electric cylinder and the risk of water leakage. In order to improve the space utilization rate of the motor chamber and significantly reduce the external dimensions of the main cylinder body, the motor shaft is arranged parallel to the axis of the motor chamber and the motor shaft is offset in the direction of the actuator chamber. The end cover can seal the ports of the motor chamber and the actuator chamber.

[0006] Furthermore, a gear chamber is provided at the other end of the main cylinder, the transmission assembly is located in the gear chamber; the motor chamber and the execution chamber are both connected to the gear chamber; and a gear chamber cover is provided at the port of the gear chamber, thereby further reducing the number of parts and matching parts, and improving the sealing performance of the main cylinder.

[0007] Furthermore, the motor chamber, the execution chamber, and the gear chamber are filled with normal pressure air, so that when the motor works underwater, each chamber maintains a certain pressure.

[0008] Furthermore, a speed reduction mechanism is provided in the motor chamber, and the speed reduction mechanism is provided between the motor and the transmission assembly. The speed reduction mechanism can increase the output torque of the motor and the transmission efficiency, and at the same time reduce the inertia of the transmission assembly and increase the working stability.

[0009] Furthermore, the outer walls of the motor chamber and the execution chamber are both square structures. Compared with arc surfaces or polyhedrons, the outer walls adopt a square structure to ensure that other accessories have sufficient installation surfaces and are convenient for the installation and fixation of accessories.

[0010] Furthermore, the outer wall of the motor chamber is provided with a watertight joint, which can maintain the sealing performance of the motor chamber in a harsh underwater environment and ensure the normal operation of the device underwater.

[0011] Furthermore, the end cover includes a motor chamber cover and an execution chamber cover; the push rod passes through the execution chamber cover. The split design of the end cover facilitates the inspection and maintenance of the internal parts of the motor chamber and the execution chamber.

[0012] Furthermore, sealing elements are provided on the peripheral sides of the end cover and the gear chamber cover.

[0013] Furthermore, a support ring and a sealing member are provided between the push rod and the execution chamber cover.

[0014] The advantages of the present invention are: 1) The present invention integrates the execution chamber, gear chamber, motor chamber and other components into a main cylinder body, which can be sealed only by the end cover and gear chamber cover, reducing the difficulty of sealing. 2) When working underwater, the underwater pressure presses the end cover and gear chamber cover tightly on the main cylinder body, and increases its sealing performance through its own structure, further reducing the risk of water leakage inward, and has good adaptability to underwater environment. 3) Since the external dimensions of the electrical interface of the motor are non-axis symmetrical structures, through the three-dimensional model design, the axis of the motor is moderately offset, that is, the axis of the motor does not coincide with the axis of the motor chamber, which can meet the placement space of the motor and the reduction mechanism, and at the same time, the required size of the motor chamber is smaller and the structure is more compact. 4) The present invention is improved on the basis of the mechanism of the traditional parallel electric cylinder, and some main components can be used in common with the traditional parallel electric cylinder, which reduces the production cost and is environmentally friendly. 5) The structure is compact and can be applied to various underwater detection and engineering machinery, and the hydraulic cylinder currently used can be replaced by electrification. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a three-dimensional diagram of the compact underwater electric cylinder of the present invention;

[0016] Figure 2It is a cross-sectional view of the compact underwater electric cylinder of the present invention;

[0017] Figure 3 It is a schematic diagram of the main cylinder body in the compact underwater electric cylinder of the present invention;

[0018] Figure 4 It is a partial schematic diagram of the compact underwater electric cylinder of the present invention;

[0019] Figure 5 It is a schematic diagram of the offset installation of the motor shaft in the compact underwater electric cylinder of the present invention;

[0020] Figure 6 This is a comparison chart between motor shaft offset installation and motor shaft coaxial installation.

[0021] In the figure, 1 is the end cover, 2 is the main cylinder body, 3 is the guide hole, 4 is the motor chamber cover, 5 is the execution chamber cover, 6 is the watertight joint, 7 is the bearing group, 8 is the gear chamber cover, 9 is the motor, 10 is the planetary reducer, 11 is the driving gear, 12 is the driven gear, 13 is the screw rod, 14 is the screw rod nut, 15 is the screw rod support, 16 is the push rod, 17 is the gear chamber, 18 is the motor chamber, 19 is the execution chamber, 20 is the support ring, 22 is the inner cavity of the waterproof cabin, a1 is the axis of the motor chamber, b is the motor shaft, and a2 is the axis of the inner cavity of the waterproof cabin. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0023] In order to facilitate machining while ensuring the accuracy of part dimensions, traditional electric cylinders generally have independent or partially integrated parts such as the cylinder body, gear box, bearing seat and other shell components of the traditional electric cylinder. However, for underwater environments, too many parts will increase the fitting parts, making it more difficult to seal the inner cavity of the electric cylinder and increasing the risk of water leakage. Underwater electric cylinders require a waterproof cabin for the motor. The inner cavity of the waterproof cabin is generally a cylindrical cavity to ensure the structural strength to withstand external water pressure. For ease of installation and processing, the motor shaft b is coaxially arranged with the axis a2 of the inner cavity of the waterproof cabin. For rotating parts such as gears and screws in the electric cylinder, the external dimensions of the electrical interface of the drive motor are not symmetrical along the axis. This design has low space utilization for the inner cavity 22 of the waterproof cabin and greatly increases the external dimensions of the underwater electric cylinder. Figure 6 As shown, if the drive motor installation axis is not designed to be offset, the diameter of the motor waterproof cabin needs to be increased to the size indicated by the dotted line, and the outer wall of the cabin and the outer dimensions of the electric cylinder also need to be expanded accordingly.

[0024] In order to solve the problems of the prior art, the present invention provides a compact underwater electric cylinder. Figures 1 to 6As shown, it includes a main cylinder body 2, an end cover 1, an actuator, a drive assembly and a transmission assembly. Among them, the actuator assembly includes a push rod 16, a screw 13, a screw support 15 and a screw nut 14, the drive assembly includes a motor 9, and the actuator assembly includes a driving gear 11 and a driven gear 12. The left end of the main cylinder body 2 is provided with a motor chamber 18 and an actuator chamber 19, the drive assembly is located in the motor chamber 18, and the actuator is located in the actuator chamber 19; the right end of the main cylinder body 2 is provided with a gear chamber 17, and the transmission assembly is located in the gear chamber 17. The motor shaft b is arranged parallel to the axis a1 of the motor chamber and the motor shaft b is offset toward the direction of the actuator chamber 19. Compared with the traditional underwater electric cylinder, the motor chamber 18 has a higher space utilization rate and a more compact internal and overall structure. The motor chamber 18 and the actuator chamber 19 are both connected to the gear chamber 17. The end cover 1 is buckled on the left end of the main cylinder 2 and seals the ports of the motor chamber 18 and the actuator chamber 19. The gear chamber 17 is sealed by the gear chamber cover 8. The motor chamber 18, the actuator chamber 19, and the gear chamber 17 are filled with normal pressure air.

[0025] The end cover 1 is provided with a guide hole 3, and the left end of the push rod 16 passes through the guide hole 3, and the right end of the push rod 16 is threadedly connected to the screw rod 13 through the screw nut 14. The left end of the screw rod 13 extends into the push rod 16 and is screwed to the screw rod 13 support, and the right end of the screw rod 13 passes through the bearing group 7 and is coaxial and fixedly connected with the driven gear 12. Preferably, the screw rod 13 is a ball screw 13. The bearing group 7 is clamped at the connection between the execution chamber 19 and the gear chamber 17, and the connection serves as a bearing seat. Since the bearing group 7 does not need to be installed with a bearing seat separately, and is installed inside the main cylinder body 2, when the external water pressure is high, the situation where the bearing seat connection in the traditional electric cylinder is prone to water seepage is avoided. The motor 9 is connected to the driving gear 11 in a transmission manner.

[0026] As a further improvement of the present invention, a reduction mechanism is further provided in the motor chamber 18, and the reduction mechanism is provided between the motor 9 and the driving gear 11. The reduction mechanism is preferably a planetary reducer 10. The structural design of the planetary gear can squeeze out a larger torque, thereby increasing the torque output by the motor 9; it can also achieve accurate conversion from high speed to low speed, reduce the adverse effects caused by inertia, and increase working stability.

[0027] As a further improvement of the present invention, the end cover 1 includes a motor chamber cover 4 and an execution chamber cover 5, and the guide hole 3 is provided on the execution chamber cover 5. The motor chamber cover 4, the execution chamber cover 5 and the gear chamber cover 8 are all provided with sealing members on their circumferential sides; a support ring 20 and a sealing member are provided between the guide hole 3 and the push rod 16. In this embodiment, the sealing member is preferably an O-ring, which is used to seal and isolate the internal and external environments of the main cylinder body 2 to ensure the sealing performance of the main cylinder body 2.

[0028] As a further improvement of the present invention, the outer walls of the motor chamber 18 and the execution chamber 19 are both square structures. The outer wall of the motor chamber 18 is provided with a watertight joint 6. The motor 9 is connected to the driving power supply and the control signal through the watertight joint 6 installed on the main cylinder body 2.

[0029] During operation, the motor 9 rotates clockwise or counterclockwise, and the ball screw 13 rotates clockwise or counterclockwise through the transmission of the planetary reducer 10 and other components, thereby driving the screw nut 14 and the push rod 16 to move forward and backward along the axis.

[0030] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A compact underwater electric cylinder, comprising an actuator, a drive assembly and a transmission assembly, wherein the actuator comprises a push rod and a screw rod, and the drive assembly comprises a motor, characterized in that: It also includes a main cylinder body and an end cover, wherein a motor chamber and an execution chamber are provided at one end of the main cylinder body, the drive assembly is located in the motor chamber, and the execution assembly is located in the execution chamber; the motor shaft is arranged parallel to the axis of the motor chamber and offset toward the execution chamber; the end cover can seal the ports of the motor chamber and the execution chamber.

2. The compact underwater electric cylinder according to claim 1, characterized in that: A gear chamber is provided at the other end of the main cylinder body, and the transmission assembly is located in the gear chamber; the motor chamber and the execution chamber are both connected to the gear chamber; and a gear chamber cover is provided at the port of the gear chamber.

3. The compact underwater electric cylinder according to claim 2, characterized in that: The motor chamber, the execution chamber, and the gear chamber are filled with normal pressure air.

4. The compact underwater electric cylinder according to any one of claims 1 to 3, characterized in that: A speed reduction mechanism is also provided in the motor chamber, and the speed reduction mechanism is arranged between the motor and the transmission assembly.

5. The compact underwater electric cylinder according to claim 1, characterized in that: The outer walls of the motor chamber and the execution chamber are both square structures.

6. The compact underwater electric cylinder according to claim 1, characterized in that: The outer wall of the motor chamber is provided with a watertight joint.

7. The compact underwater electric cylinder according to claim 1, characterized in that: The end cover comprises a motor cavity cover and an execution cavity cover; the push rod passes through the execution cavity cover.

8. The compact underwater electric cylinder according to claim 2, characterized in that: The peripheral sides of the end cover and the gear chamber cover are both provided with sealing members.

9. The compact underwater electric cylinder according to claim 7, characterized in that: A support ring and a sealing member are provided between the push rod and the execution chamber cover.

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