Miniaturized electric execution structure

Abstract

The utility model belongs to the technical field of handheld hydraulic tools driven by electric control servo equipment, and discloses a miniaturized electric actuating structure. According to the scheme, a servo hydraulic execution device adopting a one-way cam component to drive an overflow pressure relief structure and a hydraulic handheld tool applying the servo hydraulic execution device are included, and based on the one-way cam component scheme, forward rotation and reverse rotation of a servo structure of the execution device are both utilized; according to the utility model, the volume of equipment is compressed, the linkage transmission mode of the overflow pressure relief structure is optimized, the reliability of the handheld hydraulic tool is improved, the lightweight of the hydraulic tool and the optimization of the manufacturing cost are facilitated, the requirements of a construction site on the specifications and the number of different construction tools are reduced, and the construction efficiency is improved. And the method has clear popularization and application values.

Description

Technical Field

[0001] This utility model belongs to the technical field of handheld hydraulic tools driven by electronically controlled servo devices. Specifically, this utility model discloses a miniaturized electric actuator structure for hydraulic tools. Background Technology

[0002] Handheld hydraulic tools are used in applications requiring high thrust output, such as wire cutters, pipe clamps, and spreaders. The biggest feature of these tools is that they integrate a general hydraulic power system into a handheld device, providing great convenience for daily work. The actuator of a handheld hydraulic tool typically consists of a geared motor, a reducer piston, and a pressure relief structure. For a compact design, the pressure relief structure usually shares a geared motor as its power source with the piston via a linkage. To form the necessary transmission relationship and meet structural strength requirements, the design specifications of the pressure relief structure strictly adhere to the output pressure of the hydraulic tool. If there are multiple hydraulic tools with different output specifications, then multiple pressure relief structures of different specifications are necessarily required.

[0003] For example, Milwaukee has a large number of hydraulic tool technology solutions, offering numerous different design options for various specifications of hydraulic tools. In practice, construction workers do indeed need hydraulic tools with multiple output specifications to meet their requirements. For instance, a 12-ton pressure hydraulic tool and a 4-ton pressure hydraulic tool have different design requirements, and their pressure relief structures also have different pressure resistance ratings, making interchangeability impractical. Carrying and switching between numerous hydraulic tools unnecessarily burdens construction workers and increases operating costs. Providing a pressure relief structure that is compatible with multiple output pressure specifications would significantly reduce the cost of using hydraulic tools. Utility Model Content

[0004] To address the technical deficiencies in the prior art, this utility model proposes a miniaturized electric actuator structure, which solves the aforementioned technical problems and meets practical needs. The specific technical solution is as follows:

[0005] A miniaturized electric actuator includes a servo motor and a reduction gearbox, as well as an actuator. The reduction gearbox includes an input shaft, an output shaft, and a reduction gear set connected between the input shaft and the output shaft. A one-way cam component and a drive cam are connected between the input shaft and the actuator. The one-way cam component consists of a one-way bearing component sleeved on the output shaft, a cam component sleeved on the outer edge of the one-way bearing component, a trigger hook extending radially outward along the output shaft and in force contact with the outside of the cam component, and a component housing. The one-way bearing component and the drive cam are adjacent to each other. The trigger hook is connected to an overflow valve, and the movement of the trigger hook triggers the overflow valve to perform a pressure relief action. The overflow valve is connected to the hydraulic circuit of the actuator. The one-way bearing component and the cam component are coaxially hinged in the component housing.

[0006] As a further technical solution of the utility model, the actuator includes a hydraulic piston cylinder, an elastic plunger connected to the internal hydraulic passage of the hydraulic piston cylinder and used to drive the piston to reciprocate, a pressure sensor connected to the internal hydraulic passage of the hydraulic piston cylinder and used to sense the internal pressure of the hydraulic piston cylinder, the overflow valve connected to the internal hydraulic passage of the hydraulic piston cylinder, and the elastic plunger abutting against the drive cam.

[0007] As a further improvement to the previous technical solution, the overflow valve includes an overflow valve piston that communicates with the internal hydraulic passage of the hydraulic piston cylinder and an overflow valve cover that elastically abuts against the overflow valve piston. The overflow valve piston passes through the overflow valve cover and is provided with a traction hook relative to the trigger hook. The hook surface profile of the traction hook is U-shaped. There is a gap 1 between the upper edge of the hook surface of the traction hook and the upper end face of the trigger hook, and there is a gap 2 between the lower edge of the hook surface and the hook surface of the trigger hook, and the gap 1 is greater than the gap 2.

[0008] As a further improvement to the previous technical solution, the end shape of the trigger block that cooperates with the traction hook is a T-shape that adapts to the contour of the hook surface of the traction hook.

[0009] As a further technical solution of the utility model, the outer ring of the cam component is nested in the inner ring of a common bearing, and the outer ring of the common bearing is fixedly connected to the trigger hook.

[0010] As a further technical solution of the utility model, the inner ring of the one-way bearing component is interference-fitted with the output shaft, and the outer ring is interference-fitted with the inner edge of the cam component.

[0011] As a further improvement to the previous technical solution, the outer wall of the component housing is fixedly connected to the housing of the reduction gearbox, and the inner cavity of the component housing is provided with movable chambers for the drive cam and the one-way cam component to move and communicate with each other. The actuator is located inside the component housing, and a movable groove for the trigger hook to move is provided between the overflow valve and the movable chamber.

[0012] As a further improvement to the previous technical solution, the component housing is also connected to a pressure sensor that is connected to the internal hydraulic circuit of the hydraulic piston cylinder, and the pressure sensor is connected to the electrical signal of the servo motor.

[0013] The beneficial effects of this utility model are as follows:

[0014] Compared with existing technologies, this invention simplifies the design requirements of the linkage mechanism for the pressure relief structure and optimizes the execution method of the pressure relief action. The servo mechanism can quickly trigger the pressure relief structure to release pressure with just a simple reverse rotation. Furthermore, due to the simplified linkage mechanism of the pressure relief structure, the strength of the pressure relief structure can be increased accordingly, and the execution of the pressure relief action becomes more efficient and faster. Therefore, this execution structure can be adapted to hydraulic tools with different pressure values, which can reduce the complexity of tool adaptation for construction personnel and reduce the operational intensity of construction. In addition, the reliability of the structure is also good, and the stability is improved compared with the configuration of existing technologies. Therefore, it has good promotion and application value. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the planar structure of the miniaturized electric actuator described in this utility model.

[0016] Figure 2 This is a magnified schematic diagram of a portion of the pressure relief valve location in the miniaturized electric actuator of this utility model.

[0017] Figure 3 This is a schematic diagram illustrating the application of the miniaturized electric actuator structure described in this utility model.

[0018] The components include: servo motor 1, reduction gearbox 2, input shaft 20, output shaft 21, reduction gear set 22, drive cam 23, one-way bearing 3, cam 4, trigger hook 5, component housing 6, movable chamber 60, movable groove 61, overflow valve 7, overflow valve piston 70, overflow valve cover 71, traction hook 72, gap one 73, gap two 74, ordinary bearing 8, actuator 9, hydraulic piston cylinder 90, elastic plunger 91, pressure sensor 92, mounting housing 10, handheld part 100, controller 101, left force receiving part 102, right force receiving part 103, and force receiving surface 104. Detailed Implementation

[0019] The embodiments of this utility model will be described below with reference to the accompanying drawings and related examples. The embodiments of this utility model are not limited to the following examples, and this utility model relates to relevant necessary components in this technical field, which should be regarded as well-known technology in this technical field and can be known and mastered by those skilled in this technical field.

[0020] Combination Figure 1 and Figure 2 As shown, the miniaturized electric actuator includes a servo motor 1 and a reduction gearbox 2, as well as an actuator 9. The reduction gearbox 2 includes an input shaft 20, an output shaft 21, and a reduction gear set 22 connecting the input shaft 20 and the output shaft 21. A one-way cam component and a drive cam 23 are connected between the input shaft 21 and the actuator. The one-way cam component consists of a one-way bearing 3 sleeved on the output shaft 21, a cam 4 sleeved on the outer edge of the one-way bearing 3, and extends radially outward along the output shaft 21 and is subjected to force. The component consists of a trigger hook 5 that contacts the outside of the cam component 4 and a component housing 6. The one-way cam component only outputs torque from the reciprocating cam motion of the output shaft 21 when it rotates in one direction. The one-way bearing component 3 is adjacent to the drive cam 23. The trigger hook 5 is connected to an overflow valve 7, and the overflow valve 7 is triggered to release pressure as the trigger hook 5 moves. The overflow valve 7 is connected to the hydraulic circuit of the actuator. The one-way bearing component 3 and the cam component 4 are coaxially hinged in the component housing 6.

[0021] Can be combined Figures 1 to 3 As shown, specifically, compared to the common overflow valve linkage structure configuration in the existing "linkage-spring-swing arm" and other existing technologies, the configuration described in this utility model, although also using the same servo motor (the power source for driving the output action of the hydraulic actuator) for driving, has an extremely simple triggering method for servo-type structures. Specifically, when the internal pressure of the actuator needs to be released, the servo motor 1 moves directly in the opposite direction to the torque direction of the driving pressurization, which triggers the one-way cam component coaxial with the output shaft 21 near the drive cam 23, and then the one-way cam component drives the overflow valve 7 connected to it to release pressure. As long as the delay of the "stop-reverse" action of the servo motor 1 is low enough, the delay of the pressure relief action response can be almost instantaneous.

[0022] When the output shaft 21 rotates forward, it directly drives the drive cam 23 to move, which is consistent with other hydraulic tools driven by existing hydraulic servo mechanisms. It also drives the actuator 9 to output the required action force. The one-way cam component is regarded as equivalent to a normal bearing pair and will not trigger the linkage relief valve 7 because the direction of movement is not in the self-locking direction of the one-way bearing component 3. When pressure relief is required, a reverse command is given to the servo motor 1. The servo motor 1 performs a reverse action, which triggers the self-locking of the one-way bearing component 3. The inner and outer rings of the one-way bearing component 3 can be regarded as a rigid whole. The cam component 4, which is sleeved with the one-way bearing component 3, will also be driven at this time. The characteristic of the cam movement is that it is periodically fluctuating. Therefore, it can drive the trigger hook 5 to perform a reciprocating action. The relief valve 7 changes with the periodic action of the trigger hook 5, between the triggered opening state and the automatic reset state.

[0023] For example, when pressure relief is required, the one-way cam component drives the relief valve 7 to the pressure relief state. The hydraulic oil in the actuator 9 will be released as a result of the relief valve 7, thus relieving pressure on the actuator 9. After the pressure relief is completed, the relief valve 7 can return to its original closed state by its own reset action. The one-way cam component can then trigger the relief valve 7 to relieve pressure again with the next reverse rotation of the servo motor 1. This cycle repeats. The one-way cam component does not trigger the reset of the relief valve 7. The reset action is a basic function of the relief valve 7 itself, which will not be elaborated here.

[0024] Prior art, in order to ensure the accuracy of transmission, almost always sacrifices the "immediacy" and reliability of response to some extent. Generally speaking, the pressure relief linkage structure of the above-mentioned prior art can achieve a similar technical effect of timely response execution by increasing the action execution delay of the servo power source in the overall pressure relief action. However, the above-mentioned more complex structure—not to say that the structure is too complex, but that its compositional complexity is greater than that of the pressure relief structure of this utility model—is more likely to fail completely if one of the components fails during the linkage execution process.

[0025] However, this problem can be overcome by the structure described in this utility model. The pressure relief structure of the overflow valve 7 connected to the output shaft 21 of this utility model is a trigger hook 5 directly connected by several coaxially connected rotating bodies. The trigger hook 5 directly triggers the pressure relief action of the overflow valve 7 in a physical manner. There are no linkage parts with different modes of movement between the output shaft 21 and the overflow valve 7. They are only connected by a one-way bearing 3 and a cam 4, both of which are rotating bodies that rotate around the output shaft 21. They only have rolling or frictional contact with each other. Therefore, the transmission efficiency is extremely high, the response time is short, and the stability is excellent.

[0026] After the servo motor 1 of this utility model is decelerated by the gear reducer 2—which is consistent with the servo power structure of existing hydraulic tools—its output shaft 21 only needs to rotate to directly drive the actuator 9 or the relief valve 7 to perform actions with a near-consistent response speed. In addition, the component housing 6 used to assemble the above-mentioned linkage structure can accommodate the linkage structure of the relief valve 7. The one-way bearing component 3 and the cam component 4 are coaxial with the drive cam 23. Therefore, the drive cam 23 can achieve the bearing matching assembly method by relying on the component housing 6, so that it can obtain the same execution environment as the one-way cam component in the case of the same output shaft 21. Thus, they can form a mutually constraining force pair, which is helpful for structural stability.

[0027] Based on the aforementioned structural characteristics, this invention achieves rapid mechanical pressure relief through the simple action of the servo motor 1. Therefore, based on the pressure sensor or the operator's experience, the servo motor 1 can be actively and quickly switched to reverse mode at appropriate times to drive the trigger hook 5 to actuate the pressure relief valve 7. In some high-pressure applications, the trigger hook 5 can also serve as a support for the pressure relief valve 7 (specifically, the top of the trigger hook 5 can press against the pressure relief valve 7 to maintain pressure; reversing the action during pressure relief opens the valve 7). This eliminates the need to overly consider the pressure relief valve 7 itself. Therefore, compared to conventional pressure relief structures, this invention's miniaturized electric actuator offers greater adaptability to various specifications.

[0028] Based on the above characteristics, assuming that a construction site originally required 10 different specifications of hydraulic tools with pressure relief structures, after applying the technical solution of this utility model, the number of specifications can be reduced to at least 3 or even less. It is entirely feasible for each specification to be directly compatible with the original 3-4 adjacent specifications, which obviously represents a substantial improvement over the existing technical solutions.

[0029] Combination Figure 3 As shown, the miniaturized electric actuator described in this utility model can obviously be applied to conventional hydraulic tools, such as spreaders, wire cutters, pipe connectors, and other handheld tools. The aforementioned highly simplified, integrated, and efficient actuator can well meet the needs of handheld tools that are highly sensitive to installation size. It can simplify the drive actuator structure of hydraulic tools to a great extent, thus allowing hydraulic tool designers and manufacturers to better consider optimizing the controllability of hydraulic tools. In addition, the improved reliability brought about by the simplification of the structure also makes it a necessary condition for application as a standard structural component in more other tool structures that meet the production standards of hydraulic tools.

[0030] Reference Figure 1 and Figure 2 As shown, in order to further illustrate the application of the miniaturized electric actuator structure of this utility model, the preferred embodiment will be further described below. In one of the preferred embodiments of this utility model, the actuator 9 includes a hydraulic piston cylinder 90, an elastic plunger 91 that communicates with the internal hydraulic passage of the hydraulic piston cylinder 90 and drives the piston to reciprocate, and a pressure sensor 92 that communicates with the internal hydraulic passage of the hydraulic piston cylinder 90 and senses the internal pressure of the hydraulic piston cylinder 90. The overflow valve 7 communicates with the internal hydraulic passage of the hydraulic piston cylinder 90, and the elastic plunger 91 abuts against the drive cam 23.

[0031] Obviously, the structure of the actuator 9 is no different from that of the existing structure. The pressure sensor 92 can directly sense the internal pressure of the hydraulic piston cylinder 90, so that when the pressure of the structure reaches the limit or the pressure is constantly being reported, the operator can capture this information and, according to the setting of the hydraulic tool, either automatically drive the servo motor 1 to reverse to drive the one-way cam component to start the relief valve 7 to release pressure, or manually drive the servo motor 1 to reverse to drive the one-way cam component to start the relief valve 7 to release pressure. Both methods can be used to operate the hydraulic tool in a timely and safe manner to release pressure, thereby achieving the desired pressure release effect. The drive cam 23 directly abuts against the elastic plunger 91 used to drive the hydraulic piston cylinder 90, which clearly shows that the complexity of the drive power structure and the pressure release structure are almost equal and their spatial heights are close. This fully reflects that the miniaturized electric actuator structure described in this utility model can meet the performance indicators of lightweight, compact and stable hydraulic action execution requirements.

[0032] Reference Figure 2 As shown, the overflow valve 7 includes an overflow valve piston 70 communicating with the internal hydraulic passage of the hydraulic piston cylinder 90, and an overflow valve cover 71 elastically abutting against the overflow valve piston 70. The overflow valve piston 70 passes through the overflow valve cover 71 and is provided with a pulled hook 72 relative to the trigger hook 5. The hook surface profile of the pulled hook 72 is U-shaped. Furthermore, combined with Figure 3 As shown, the end shape of the trigger block 5 that cooperates with the traction hook 72 is a T-shape that fits the outline of the hook surface of the traction hook. There is a gap 73 between the upper edge of the hook surface of the traction hook 72 and the upper end surface of the trigger hook 5, and there is a gap 74 between the lower edge of the hook surface and the hook surface of the trigger hook 5. The gap 73 is larger than the gap 74.

[0033] Clearly, the trigger hook 5 is not fixedly connected to the overflow valve piston 70, but rather spatially engages with the traction hook 72 through gaps 73 and 74, rather than being directly connected under force in the normal state. The overflow valve piston 70, as... Figure 3The diagram shows a piston rod passing through the overflow valve cover 71, connecting to a traction hook 72. The overflow valve cover 71 provides a support surface for the elastic reset element and seals against the piston rod, thus forming a controllable connection. This connection only occurs when the pressure relief valve 7 needs to be depressurized. The output shaft 21 drives the one-way cam component to rotate downwards in the self-locking direction, driving the trigger hook 5 closer to the traction hook 72. The gap 1 73 increases while the gap 2 74 decreases until the two hooks are in contact. The trigger hook 5 then pulls the traction hook 72 downwards, causing the overflow valve piston 70 connected to it to move downwards relative to the overflow valve cover 71, overcoming its own elastic force. In other words, it moves towards the trigger hook 5, causing the overflow valve piston 70 to disengage from its original position and open the pressure relief fluid path, thereby realizing the pressure relief action of the overflow valve 7 and meeting the operational needs of the hydraulic tool. Furthermore, the T-shape of the trigger hook 5 and the U-shape of the traction hook 72 work together to prevent the structure from easily dislodging when subjected to external vibrations, which greatly contributes to the stability of the structure.

[0034] In this design, gap 73 needs to be larger than gap 74. The smaller gap 73 is, the shorter the trigger stroke required for the trigger hook 5 to pull the pressure relief valve 7 to release pressure, and thus the shorter the response time. As a necessary and reasonable technical feature, gap 73 needs to be smaller than the trigger stroke of the trigger hook 5. This ensures that the trigger hook 5 can trigger the pressure relief valve 7 to release pressure without affecting the normal elastic reset of the pressure relief valve 7. Similarly, if gap 74 is larger than the maximum stroke of the trigger hook 5, it ensures that when the trigger hook 5 moves towards the pressure relief valve 7, it will not collide with the traction hook 72, causing damage to the components. The compactness reflected by the above structure, as a technical feature, makes the one-way cam component linkage structure of this utility model a preferred solution compared to the prior art. It is also one of the fundamental guarantees that the one-way cam component can correctly trigger the pressure relief valve 7 to act according to the forward and reverse rotation of the servo motor 1.

[0035] Therefore, as can be directly reflected from the above description, the pressure relief valve 7 linkage structure of this utility model has good mechanical reliability and ease of operation. The stability of the structure is sufficient to support its adaptation to a wider range of hydraulic tools with different pressure output specifications. This reduces the dependence on the number of hydraulic tools of various specifications on the construction site, reduces the workload of construction personnel in construction preparation, and reduces the complexity of operating tools on the construction site. It is of great help in reducing construction costs and improving construction efficiency.

[0036] Reference Figure 1 or Figure 2As shown, in one preferred embodiment of this utility model, the cam component 4 is nested within the inner ring of a common bearing 8, and the outer ring of the common bearing 8 is fixedly connected to the trigger hook 5. To better achieve transmission and ensure that the trigger hook 5 maintains almost its original orientation during the reciprocating eccentric motion of the cam, thus facilitating the drive of the overflow valve cover 71 of the overflow valve 7, the use of the common bearing 8 allows the overflow valve 7 and the one-way cam component to form a complete engine piston-like structure, thereby reliably transmitting torque from the output shaft 21 under the self-locking condition of the one-way bearing component 3. The torque is a configuration that can better achieve the required reciprocating motion. Without the setting of ordinary bearing 8, trigger hook 5 can also be directly connected to cam 4 to achieve a similar technical effect. However, the connection surface between trigger hook 5 and cam 4 is smaller (preferably, trigger hook 5 is hinged to the edge of cam 4 to ensure transmission consistency). Its stability is relatively weaker. However, since the linkage structure of pressure relief valve 7 is not a structure that operates as frequently as the pressure application structure of drive cam 23, its requirements for structural strength are not so high. Therefore, it can still meet the usage requirements of most occasions.

[0037] In one preferred embodiment of this utility model, the inner ring of the one-way bearing 3 is interference-fitted with the output shaft 21, and the outer ring is interference-fitted with the inner edge of the cam 4. The above-mentioned technical structure is the basic guarantee for ensuring stable cooperation between the one-way bearing 3, the output shaft 21, and the cam 4. Especially in the reverse self-locking state, it can enable the output shaft 21 to accurately transmit torque to the trigger hook 5 of the final linkage, ensuring the timeliness and consistency of the transmission, while also ensuring the stability of the structure. This is an advantage that makes the overflow valve linkage structure of this utility model different from the existing structure. In particular, under the premise that the number of linkage components in the overflow valve linkage structure of this utility model is less, a stable connection is a necessary condition to ensure reliable transmission of action.

[0038] Reference Figure 1 or Figure 2 As shown, as a further preferred embodiment compared to the previous one, the outer wall of the component housing 6 is fixedly connected to the housing of the reduction gearbox 2. The inner cavity of the component housing 6 is provided with movable chambers 60 that are respectively for the drive cam 23 and the one-way cam component to move and are interconnected. The actuator 9 is located inside the component housing 6. A movable groove 61 for the trigger hook 5 to move is provided between the overflow valve 7 and the movable chamber 60. The component housing 6 is the basis for setting the miniaturized electric actuator structure of this utility model. If it can be set together with the actuator 9 and the one-way cam component, it can meet the design requirements of the compact structure. The sharing of the movable chamber 60 helps the closed circulation of hydraulic oil to ensure the stability of the structure. As for the setting of the movable groove 61, it mainly plays a technical role in guiding the trigger hook 5 to move better.

[0039] Reference Figure 1or Figure 2 As shown, in a further preferred embodiment, the component housing 6 is also connected to a pressure sensor 92 that is connected to the internal hydraulic circuit of the hydraulic piston cylinder 90. The pressure sensor 92 is electrically connected to the servo motor 1. The beneficial effects of this embodiment have been described above and will not be repeated here. Specifically, if the pressure sensor 92 has a suitable automatic control structure, its electrical signal can directly act on the servo motor 1, which facilitates the hydraulic tool to perform an emergency safety unlocking action and can play a better role in certain situations.

[0040] To better illustrate the specific application of the miniaturized electric actuator structure described in this utility model, combined with Figure 3 The hydraulic tool shown uses the electric actuator structure described in this utility model and also includes a mounting housing 10 for mounting and fixing the miniaturized electric actuator structure. The mounting housing 10 is provided with a handheld part 100 for hand operation and a controller 101 electrically connected to the actuator 9 and the servo motor 1. The mounting housing 10 is also connected to a left force-receiving part 102 and a right force-receiving part 103 that are hinged to each other and connected to the output end of the actuator 9. Under the action of the positive force at the output end of the actuator 9, the angle or distance between the left force-receiving part 102 and the right force-receiving part 103 around the common hinge point rigidly increases. Under the influence of the overflow valve 7 driven by the reverse force of the actuator 9, the force applied to the actuator 9 is lost and the actuator is finally reset.

[0041] In this structure, the output end of the miniaturized electric actuator 9 directly acts on the left force-receiving part 102 and the right force-receiving part 103, which are hinged to each other on the mounting housing 10. Specifically, if the left force-receiving part 102 and the right force-receiving part 103 are hinged to each other, when the actuator 9 is pressed against the hinge point through the linkage structure or directly, the relative movement will cause the left force-receiving part 102 and the right force-receiving part 103 to move away from each other or move closer to each other, thereby achieving the desired action. For example, Figure 3 This structure is designed for clamping pipes. The left force-bearing part 102 and the right force-bearing part 103 are hinged to each other. This structure also needs to be positioned and assembled with the mounting housing 10 through positioning points. If a roller that can simultaneously abut against the left force-bearing part 102 and the right force-bearing part 103 is provided at the output end of the hydraulic piston cylinder 90, as the hydraulic piston cylinder 90 rises (upward in the direction shown in the attached figure), the roller will advance along the surface relative to the contact surface of one end of the left force-bearing part 102 and the right force-bearing part 103, just like a lever structure. The other ends of the left force-bearing part 102 and the right force-bearing part 103, like a lever, will move closer to each other around the common hinge point, thereby completing the clamping action. The structure of the wire cutter and the expander is similar, and will not be described in detail here.

[0042] The handheld part 100 is a grip structure that facilitates operation by the operator, while the controller 101 is a necessary electrical control structure that facilitates the operator to operate the servo motor 1 to rotate forward and backward to achieve the required actions. Theoretically, the controller 101 only needs to directly control the forward and reverse rotation of the servo motor 1 to change the action mode of the hydraulic tool, so as to apply pressure or release pressure. However, further, additional sensing structures such as pressure sensor 92 can be set to help the operator better grasp the working status of the tool, thereby improving the safety of construction operations.

[0043] The force-bearing surfaces 104 of the left force-bearing part 102 and the right force-bearing part 103 are located on opposite sides or opposite sides of each other. The force-bearing surface 104 is also the plane on which the actual pressure is released. The different arrangements of these surfaces determine the application scenarios of the hydraulic tools. For example, refer to Figure 3 As shown, when the force-bearing surface 104 is on the opposite side, the left force-bearing part 102 and the right force-bearing part 103 usually need to apply clamping or shearing force—depending on the structural form of the left force-bearing part 102 and the right force-bearing part 103. Such tools are generally wire cutters or pipe clamps. When the force-bearing surface 104 is on the opposite side, such tools are generally used for expansion operations, such as expanders. Because the miniaturized electric actuator structure described in this utility model is simple, compact and stable, it has good interoperability in the above-mentioned different applications and good versatility. Operators can operate hydraulic tools more easily and quickly for construction operations, and the maintenance difficulty is lower.

[0044] In summary, compared to existing technologies, this invention simplifies the design requirements of the linkage mechanism for the pressure relief structure and optimizes the execution method of the pressure relief action. The triggering speed of the pressure relief action is faster and more efficient. Furthermore, due to the simplified linkage mechanism, the strength of the pressure relief structure can be correspondingly increased. Therefore, this invention achieves the capability to adapt to hydraulic tools with multiple different pressure values, significantly reducing the complexity of tool adaptation for construction workers and the intensity of actual construction operations. In addition, the structural simplification of this invention also improves the overall reliability of the structure, making it highly valuable for promotion and application.

[0045] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A miniaturized electric actuator, comprising a servo motor and a reduction gearbox, and further comprising an actuator, wherein the reduction gearbox includes an input shaft, an output shaft, and a reduction gear set connected between the input shaft and the output shaft, characterized in that, The input shaft and the actuator are connected by a one-way cam component and a drive cam. The one-way cam component consists of a one-way bearing component sleeved on the output shaft, a cam component sleeved on the outer edge of the one-way bearing component, a trigger hook extending radially outward along the output shaft and in force contact with the outside of the cam component, and a component housing. The one-way bearing component and the drive cam are adjacent to each other. The trigger hook is connected to an overflow valve, and the overflow valve is triggered to perform a pressure relief action as the trigger hook moves. The overflow valve is connected to the hydraulic circuit of the actuator. The one-way bearing component and the cam component are coaxially hinged in the component housing.

2. The miniaturized electric actuator structure according to claim 1, characterized in that, The actuator includes a hydraulic piston cylinder, an elastic plunger connected to the internal hydraulic passage of the hydraulic piston cylinder and used to drive the piston to reciprocate, a pressure sensor connected to the internal hydraulic passage of the hydraulic piston cylinder and used to sense the internal pressure of the hydraulic piston cylinder, an overflow valve connected to the internal hydraulic passage of the hydraulic piston cylinder, and the elastic plunger abutting against the drive cam.

3. The miniaturized electric actuator structure according to claim 2, characterized in that, The overflow valve includes an overflow valve piston that communicates with the internal hydraulic passage of the hydraulic piston cylinder and an overflow valve cover that elastically abuts against the overflow valve piston. The overflow valve piston passes through the overflow valve cover and is provided with a traction hook relative to the trigger hook. The hook surface profile of the traction hook is U-shaped. There is a gap 1 between the upper edge of the hook surface of the traction hook and the upper end face of the trigger hook, and there is a gap 2 between the lower edge of the hook surface and the hook surface of the trigger hook, and gap 1 is larger than gap 2.

4. The miniaturized electric actuator structure according to claim 3, characterized in that, The end shape of the trigger hook that mates with the traction hook is a T-shape adapted to the outline of the hook surface of the traction hook.

5. The miniaturized electric actuator structure according to claim 1, characterized in that, The cam component is nested in the inner ring of a common bearing, and the outer ring of the common bearing is fixedly connected to the trigger hook.

6. The miniaturized electric actuator structure according to claim 1, characterized in that, The inner ring of the one-way bearing is interference-fitted with the output shaft, and the outer ring is interference-fitted with the inner edge of the cam component.

7. The miniaturized electric actuator structure according to claim 2, characterized in that, The outer wall of the component housing is fixedly connected to the housing of the reduction gearbox. The inner cavity of the component housing is provided with movable chambers for the drive cam and the one-way cam component to move and are interconnected. The actuator is located inside the component housing. A movable groove for the trigger hook to move is provided between the overflow valve and the movable chamber.

8. The miniaturized electric actuator structure according to claim 7, characterized in that, The component housing is also connected to a pressure sensor that is connected to the internal hydraulic circuit of the hydraulic piston cylinder, and the pressure sensor is connected to the electrical signal of the servo motor.

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