A cylinder energy storage electric push rod

Abstract

The present invention provides a new type of electric push rod with cylinder energy storage, which includes an electric push rod mainly composed of an outer cylinder, a hollow guide rod, a dust cover, a connecting fork head, a hollow piston rod with an internal control valve, a machine shell, a rotary shaft lip seal, a bearing positioning part, a rolling bearing, a lead screw, a gear set, and a motor, as well as an accumulator cylinder coaxial with the outer cylinder of the electric push rod and having an energy storage function. At one axial end of the accumulator cylinder, there is a cylinder bottom sealed with the outer cylinder of the electric push rod, and at the other end, there is a cylinder head sealed with both of them. The cylinder head, the outer cylinder of the electric push rod, the cylinder bottom, the accumulator cylinder, and the cylinder head form an energy storage chamber. In the energy storage chamber, the present invention uses gas as the energy storage medium and uses a control valve to achieve one-way replenishment of the gas in the sealed chamber. When the electric push rod retracts, the control valve closes to recover the generated pneumatic energy; when the electric push rod extends during operation, the control valve closes to release the stored pneumatic energy to assist the hollow guide rod in extending. After all the pneumatic energy in the energy storage chamber is released, the control valve opens to replenish the gas in the sealed chamber to achieve the reuse of energy. This energy storage electric push rod is energy-saving and environmentally friendly, and can be used in the engineering applications of various electric push rods to improve the energy efficiency of the transmission system.

Description

Technical Field

[0001] The present invention relates to the field of electric push rods, and more specifically to a cylinder energy storage electric push rod. Background Art

[0002] In recent years, energy regeneration technology has been widely applied in various fields. Due to resource shortages, energy conservation and environmental protection have become the main goals of production and manufacturing. An accumulator is an energy storage device in a hydraulic and pneumatic system and is widely used as an energy storage element in the field of energy regeneration technology. The accumulator converts the energy in the system into pneumatic energy and stores it at an appropriate time, and when the system needs it, it releases the pneumatic energy and replenishes it back to the system.

[0003] An electric push rod is a linear electric actuator mainly composed of mechanisms such as a motor, a push rod, and a control device, and can output linear pushing and pulling forces to drive a load to do work; generally, the motor converts rotational motion into linear pushing and pulling motion of a hollow piston rod through a lead screw. If the motor is a servo motor, servo pushing and pulling positioning can be achieved.

[0004] Electric push rods are widely used in industries such as electric power, machinery, metallurgy, transportation, chemical industry, hoisting, transportation, and construction, and are mainly designed with different thrusts according to different application loads. Disadvantages: Due to the needs of the load, the motors equipped on electric push rods often have large powers, which makes the overall structure of the electric push rod larger and the manufacturing cost higher; under limited space structure and manufacturing cost, the motor often cannot provide the power required by the load, its output capacity is limited, and its working ability cannot meet the requirements of lifting large-mass workpieces, lacking an auxiliary power supply mechanism; the energy that can be recycled during the return process of the electric push rod lifting a heavy object is not effectively utilized. Therefore, a new type of electric push rod with an energy storage function is needed to meet the usage requirements of electric push rods.

[0005] Based on the above considerations of the disadvantages and limitations of electric push rods, Fan Hongbing et al. proposed a simple model of an assisted electric push rod in the patent document CN201711380704.6. A boosting mechanism composed of a medium liquid and a hydraulic power source is installed as an external accessory around the electric push rod. Under the action of the hydraulic power source as an auxiliary power, hydraulic oil is injected into the cavity in the electric push rod to generate pressure on the piston, realizing electric and hydraulic composite drive of the load to move. This design is mainly applied to the field of driving a robot arm to lift large-mass workpieces and can effectively increase the output force of the electric push rod. However, the boosting mechanism is installed as an external accessory around the electric push rod, which greatly increases the size and complexity of the design. Summary of the Invention

[0006] The object of the present invention is to provide a cylinder energy storage electric push rod structure, which attaches the function of an accumulator to the electric push rod, uses it as an auxiliary power supply mechanism to improve the load capacity of the electric push rod, designs the transmission space of the electric push rod as a closed space, connects the closed space with a simple connecting pipeline, stores the compressed air energy in the closed space when the electric push rod returns, and releases it when the electric push rod does work on the outside world next time to provide auxiliary power for the electric push rod.

[0007] To achieve the above object, the technical solution adopted by the present invention is: a cylinder energy storage electric push rod, including an electric push rod mainly composed of an outer cylinder, a hollow guide rod, a hollow piston rod with an internal control valve, a machine shell, a rotary shaft lip seal, a connecting fork head, a dust cover, a bearing positioning part, a rolling bearing, a lead screw, a gear set, and a motor;

[0008] The motor is installed on the machine shell by screw connection, the rolling bearing is installed on the lead screw by a bearing positioning part, the outer cylinder is installed on the machine shell by screw connection, the motor in the electric push rod is provided with a gear set connected to the lead screw, and the lead screw pushes and pulls the hollow piston rod and the hollow guide rod to move linearly in the outer cylinder;

[0009] One end of the outer cylinder is provided with an end cover sealed with the lead screw, and the lead screw, the end cover, the outer cylinder, and the hollow piston rod with an internal control valve form a sealing cavity Ⅰ, and a section of the lead screw and the hollow piston rod with an internal control valve form a sealing cavity Ⅱ;

[0010] An accumulator cylinder coaxial with the outer cylinder is provided on the outer circle of the outer cylinder. One axial end of the accumulator cylinder is provided with a cylinder bottom sealed with the outer cylinder, and the other end is provided with a cylinder head sealed with both. The outer cylinder, the cylinder bottom, the accumulator cylinder, and the cylinder head of the electric push rod form an energy storage cavity;

[0011] An energy storage piston coaxial with and slidably connected to the energy storage cavity is provided in the energy storage cavity. At least one air hole communicating with the sealing cavity Ⅰ is provided on the outer cylinder. The sealing cavity Ⅰ and the sealing cavity Ⅱ are communicated through a communication pipeline inside the lead screw, and the sealing cavity Ⅱ is communicated with the outside air through a control valve inside the hollow piston rod.

[0012] Furthermore, a sealing ring is provided between the outer circle of one end of the hollow piston rod with an internal control valve and the inner circle of the outer cylinder, a control valve is arranged inside the end face of the other end, a sealing ring is provided between the end cover and the outer cylinder, and a rotary shaft lip seal is provided between the end cover and the lead screw.

[0013] Furthermore, a sealing ring is provided between the inner ring of the energy storage piston and the outer ring of the outer sleeve cylinder, and a sealing ring is provided between the outer ring of the energy storage piston and the inner ring of the accumulator cylinder. Both the cylinder head and the cylinder bottom are hermetically connected to the accumulator cylinder through a sealing ring, and a sealing ring is provided. Both the cylinder head and the cylinder bottom are hermetically connected to the outer ring of the outer sleeve cylinder through a sealing ring.

[0014] Furthermore, a control valve is built into the end face of the hollow guide rod to control the communication between the gas in the sealing cavity II and the outside gas. When all the pneumatic energy stored in the energy storage cavity is released, the control valve opens to compensate the gas in the sealing cavity II.

[0015] Furthermore, there is a ventilation pipe inside the lead screw to connect the sealing cavity I and the sealing cavity II. Preferably, the ventilation pipe should be in an axisymmetric form and as simple as shown in the illustration to ensure the relevant performance of the lead screw.

[0016] Furthermore, the outer sleeve cylinder has at least one air hole at the bottom of the energy storage cavity, and the air hole connects the closed cavity I and the energy storage cavity.

[0017] Furthermore, a rolling bearing is installed at one end of the lead screw close to the motor, and the rolling bearing is positioned and installed by bearing positioning parts such as nuts and shaft sleeves. Preferably, the rolling bearing is a deep groove ball bearing.

[0018] For a cylinder barrel energy storage electric push rod adopting the above design scheme, compared with the prior art, the present invention is designed with a coaxial accumulator cylinder, integrating the energy storage and boosting mechanism with the traditional electric push rod, making the structure more compact, greatly reducing the equipment volume, simplifying the connecting pipelines, and reducing the system pressure loss caused by the pipelines; the present invention provides the detailed structure of a new type of electric push rod, with a detailed description of its internal structure and an image-specific implementation method, which can be used in the engineering applications of various electric push rods to improve the energy efficiency of the transmission system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 、 2 is a schematic internal structure diagram of a cylinder barrel energy storage electric push rod of the present invention;

[0020] Figure 3 is a schematic internal structure diagram of the control valve of the present invention;

[0021] Figure 4 is a three-dimensional view of a cylinder barrel energy storage electric push rod of the present invention;

[0022] Figure 5 is a schematic internal structure diagram of the lead screw of the present invention.

[0023] Reference numerals: 1, deep groove ball bearing; 2, end cover; 3, cylinder bottom; 4, outer cylinder barrel; 5, energy storage piston; 6, sealing ring; 7, hollow piston rod; 8, hollow guide rod; 9, cylinder head; 10, dust cover; 11, connecting fork head; 12, control valve; 13, motor; 14, machine housing; 15, lead screw; 16, mounting hole; 17, rotary shaft lip seal; 18, air hole I; 19, nut; 20, bearing positioning member; 21, energy storage cavity; 22, sealing cavity I; 23, ventilation pipe; 24, sealing cavity II; 25, gear set; 26, accumulator cylinder barrel; 121, air hole II; 122, spring; 123, control valve spool; 124, air hole III; 125, control valve piston. Detailed implementation manner

[0024] The present invention will be described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0025] A cylinder barrel energy storage electric push rod, comprising a machine housing 14, a motor 13, a gear set 25, a lead screw 15, a nut 19, a deep groove ball bearing 1, a bearing positioning member 20, an end cover 2, and a rotary shaft lip seal 17. It is characterized in that: the motor 13 is installed on the machine housing 14 by screw connection, the motor 13 is drivingly connected to the lead screw 15 through the gear set 25, the deep groove ball bearing 1 is installed on the lead screw 15 by using bearing positioning members 20 such as sleeves, the nut 19 and the lead screw 15 are axially positioned by screw connection to position the deep groove ball bearing 1, and the end cover 2 and the lead screw 15 are sealingly connected by a rotary shaft lip seal 17;

[0026] The novel energy storage electric push rod further includes an outer cylinder barrel 4, a hollow piston rod 7, a hollow guide rod 8, a control valve 12, a cylinder head 9, a cylinder bottom 3, an energy storage piston 5, an accumulator cylinder barrel 26, a dust cover 10, and a connecting fork head 11. Its characteristics are as follows: The outer cylinder barrel 4 is installed on the machine shell 14 by screw connection. A sealing ring is used for sealed connection between the outer cylinder barrel 4 and the end cover 2. A threaded connection is adopted between the hollow piston rod 7 and the lead screw 15. A control valve 12 is built into one end of the hollow piston rod 7, and a sealing ring is used for sealed connection between the outer circle of the other end and the inner circle of the outer cylinder barrel 4. The lead screw 15 pushes and pulls the hollow piston rod 7 and the hollow guide rod 8 to move linearly within the outer cylinder barrel 4. An interference fit is adopted for connection between the hollow guide rod 8 and the hollow piston rod 7. The threaded connection is adopted between the outer circle of the extended section of the dust cover 10 and the inner circle of the outer cylinder barrel 4, and a sliding connection is adopted between the inner circle of the dust cover 10 and the outer circle of the hollow guide rod 8. One end of the connecting fork head 11 is threadedly connected to the hollow guide rod 8, and the other end is also provided with a thread for connection to an external working object to output push and pull forces. The cylinder head 9, the cylinder bottom 3, the outer circle of the outer cylinder head 4, and the inner circle of the accumulator cylinder barrel 26 jointly form an energy storage cavity 21. The inner circle of the energy storage piston 5 is hermetically arranged and slidably connected to the outer circle of the outer cylinder barrel 4, and the outer circle of the energy storage piston 5 is hermetically arranged and slidably connected to the inner circle of the accumulator cylinder barrel 26. An air hole Ⅰ18 communicating with the sealed cavity Ⅰ22 is provided at the cylinder bottom 3 of the energy storage cavity. An air vent pipe 23 is arranged inside the lead screw 15 to communicate the sealed cavity Ⅰ22 with the sealed cavity Ⅱ24. A control valve 12 is built into the end face of the hollow piston rod 7 to control the communication between the gas in the sealed cavity Ⅱ24 and the external gas.

[0027] The specific working principle of the present invention is as follows: When the present invention works, the energy storage piston 5 is pre-pushed to a position close to the cylinder bottom 3. Under the pressure of the external load, the motor 13 rotates in reverse, and the gear set 25 drives the lead screw 15 to rotate in reverse. The lead screw 15 pulls the hollow piston rod 7, the hollow guide rod 8, and the connecting fork head 11 to slowly retract the lifted heavy object. The volumes of the sealed cavity Ⅰ22 and the sealed cavity Ⅱ24 are continuously compressed, and the pressure at the air hole Ⅱ121 continuously increases and is greater than the atmospheric pressure at the air hole Ⅲ124. Under the action of the pressure difference between the two, the control valve spool 123 is squeezed, and the control valve 12 closes; the gas in the sealed cavity Ⅰ22 and the sealed cavity Ⅱ24 is continuously compressed and enters the energy storage cavity 21 through the air hole Ⅰ18. Under the action of the air pressure, the energy storage piston 5 slides towards the cylinder head 9, converting the energy into compressed energy for storage and being used for the next lifting of the load to do work; at the same time, the air pressure in the sealed cavity Ⅰ22 and the sealed cavity Ⅱ24 continuously increases, and the air pressure reversely jacks up the hollow piston rod 7 and the hollow guide rod 8, acting reversely on the external load, reducing the extrusion force of the internal thread of the hollow piston rod 7 on the external thread of the lead screw 15, reducing the friction between the thread meshes, thereby reducing the output power of the motor to achieve the purpose of energy saving, improving the utilization rate and working efficiency of the motor, and reducing the high manufacturing cost. When the electric push rod lifts the load to work, the motor 13 rotates forward, and the gear set 25 drives the lead screw 15 to rotate forward. The lead screw 15 pushes the hollow piston rod 7, the hollow guide rod 8, and the connecting fork head 11 to slowly extend the lifted heavy object. At this time, the air pressure energy in the energy storage cavity 21 is released, and the high-pressure gas presses on the hollow piston rod 7 through the air hole Ⅰ18 and the ventilation pipe 23, providing assistance for the electric push rod to help the electric push rod output a greater thrust, and the motor controls the corresponding position of the load lifting. When all the air pressure energy in the energy storage cavity 21 is released and the hollow piston rod 7 needs to continue to extend the lifted heavy object due to the working condition requirements, at this time, the air pressure in the sealed cavity Ⅰ22 and the sealed cavity Ⅱ24 continuously decreases. When the air pressure at the air hole Ⅱ121 is less than the atmospheric pressure at the air hole Ⅲ124, under the action of the pressure difference between the two, the control valve spool 123 is squeezed, and the control valve 12 opens to compensate the gas in the sealed cavity Ⅱ24, preventing a negative pressure state from occurring in the sealed cavity Ⅰ22 and the sealed cavity Ⅱ24 and increasing the output power of the motor.

[0028] With the assistance of the energy storage cavity, smaller specifications can be selected for both the power of the motor and the strength of the lead screw, and the overall structure of the electric push rod can also be optimized.

[0029] The above has introduced the novel energy storage electric push-pull rod provided by the present invention in detail. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the core idea of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A cylinder energy storage electric push rod, characterized in that: An electric push rod mainly composed of an outer sleeve cylinder (4), a hollow guide rod (8), a control valve (12), a hollow piston rod (7), a housing (14), a rotary shaft lip seal (17), a connecting fork head (11), a dust cover (10), a bearing positioning part (20), a deep groove ball bearing (1), a lead screw (15), a gear set (25), and a motor (13); The motor (13) is installed on the housing (14) by screw connection. The deep groove ball bearing (1) is installed on the lead screw (15) by using the bearing positioning part (20). The outer sleeve cylinder (4) is installed on the housing (14) by screw connection. The motor (13) is provided with a gear set (25) connected to the lead screw (15). The lead screw (15) pushes and pulls the hollow piston rod (7) and the hollow guide rod (8) to perform a linear motion in the outer sleeve cylinder (4); One end of the outer sleeve cylinder (4) is provided with an end cover sealed with the lead screw (15). The lead screw (15), the end cover (2), the outer sleeve cylinder (4), and the hollow piston rod (7) with a control valve (12) built therein form a sealed cavity Ⅰ (22). One end of the lead screw (15) and the hollow piston rod (7) with a control valve (12) built therein form a sealed cavity Ⅱ (24); An accumulator cylinder (26) coaxial with the outer circle of the outer sleeve cylinder (4) is provided. One axial end of the accumulator cylinder (26) is provided with a cylinder bottom (3) sealed with the outer sleeve cylinder (4), and the other end is provided with a cylinder head (9) sealed with both. The outer sleeve cylinder (4), the cylinder bottom (3), the accumulator cylinder (26), and the cylinder head (9) of the electric push rod form an accumulator cavity (21); An accumulator piston (5) coaxial with and slidably connected to the accumulator cavity (21) is provided therein. The outer sleeve cylinder (4) is provided with at least one air hole Ⅰ (18) communicating with the sealed cavity Ⅰ (22). The sealed cavity Ⅰ (22) and the sealed cavity Ⅱ (24) are communicated through an air duct (23) inside the lead screw (15). The sealed cavity Ⅱ (24) is communicated with the outside air through the control valve (12) inside the hollow piston rod (7); A sealing ring is provided between the outer circle of one end of the hollow piston rod (7) with a control valve (12) built therein and the inner circle of the outer sleeve cylinder (4). A control valve (12) is inside the end face of the other end. A sealing ring is provided between the end cover (2) and the outer sleeve cylinder (4). A rotary shaft lip seal (17) is provided between the end cover (2) and the lead screw (15); A control valve (12) is built in the end face of the hollow guide rod (8) to control the communication between the gas in the sealed cavity Ⅱ (24) and the outside gas. When all the pneumatic energy stored in the accumulator cavity (21) is released, the control valve (12) opens to compensate the gas in the sealed cavity Ⅱ (24); The outer circle of the extended section of the dust cover (10) is threadedly connected to the inner circle of the outer sleeve cylinder (4), and the inner circle of the dust cover (10) is slidably connected to the outer circle of the hollow guide rod (8); One end of the connecting fork head (11) is threadedly connected to the hollow guide rod (8), and the other end is also provided with a thread for connection to the working object.

2. The cylinder energy storage electric push rod according to claim 1, characterized in that: One end of the machine shell (14) is equipped with a motor (13) and a part of the outer sleeve cylinder (4), and the other end uses screw connection to install the cylinder energy storage electric push rod at an appropriate position of the instrument.

3. The cylinder energy storage electric push rod according to claim 1, characterized in that: A sealing ring (6) is provided between the inner ring of the energy storage piston (5) and the outer ring of the outer sleeve cylinder (4). A sealing ring is provided between the outer ring of the energy storage piston (5) and the inner ring of the accumulator cylinder (26). The cylinder head (9) and the cylinder bottom (3) are both hermetically connected to the accumulator cylinder (26) through a sealing ring, and the cylinder head (9) and the cylinder bottom (3) are both hermetically connected to the outer ring of the outer sleeve cylinder (4) through a sealing ring.

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