An electric ratchet wrench

Abstract

The utility model discloses an electric ratchet wrench belongs to power tool field, has solved the problem of electric ratchet wrench structure of prior art more complex, the technical scheme of solving this problem includes being equipped with the handle of driving motor and being equipped with the head shell of transmission shaft, output head, the ratchet wheel rotatablely installed in the head shell, the ratchet wheel is equipped with the jack -in hole for installing output head, the pawl slidably installed in the head shell, the first elastic member is equipped between the head shell and pawl, the first elastic member exerts the force of the direction of ratchet wheel to pawl, makes pawl always have the tendency of engaging with ratchet wheel, the pawl is cooperated with ratchet wheel to restrict ratchet wheel to rotate only in one direction, transmission shaft with ratchet wheel is connected through gear assembly transmission, the output shaft of driving motor extends to the head shell and is connected with transmission shaft through one-way clutch. The utility model simplifies the structure of electric ratchet wrench.

Description

Technical Field

[0001] This utility model relates to the field of power tools, and in particular to an electric ratchet wrench. Background Technology

[0002] Currently available electric ratchet wrenches include parts such as handles, wrench heads, and motors. The motor's output shaft is connected to a drive shaft. The most common type has an eccentric push block on the drive shaft. The rotation of the eccentric block drives the output ratchet assembly to reciprocate. The ratchet ring has a pawl that limits the movement of the output assembly in one direction of rotation, while it slides in the opposite direction to achieve unidirectional power output. However, the eccentric mechanism has problems such as dead points and low operating efficiency, and it cannot effectively utilize the kinetic energy output by the motor, resulting in a small transmitted torque. Of course, in the existing technology, Japanese Patent JP3248824U also discloses a head shell anti-reverse mechanism that uses gear assembly transmission, including a manual reverse prevention mechanism and an electric reverse prevention mechanism. The manual reverse prevention mechanism includes: a first pawl, which is provided as a manual ratchet member opposite to the serrations of the head body; a first helical spring, which pushes the first pawl toward the side that meshes with the serrations; and a first spring receiving part, which receives the base end of the first helical spring. The electric reverse prevention mechanism, i.e., the electric power on / off mechanism, includes: a second pawl, which is provided as an electric ratchet member opposite to the gear ring; a second helical spring, which applies force to the second pawl toward the side that meshes with the gear ring; and a second spring seat, which receives the base end of the second helical spring. The head shell is provided with a double ratchet anti-reverse mechanism, which has a relatively complex structure and is not conducive to installation and maintenance. Utility Model Content

[0003] The purpose of this invention is to provide an electric ratchet wrench that solves the problem of the complex structure of existing electric ratchet wrenches and simplifies the structure of electric ratchet wrenches.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: an electric ratchet wrench, comprising a handle with a drive motor and a head housing with a transmission shaft and an output head. A ratchet is rotatably mounted inside the head housing, and the ratchet has a socket for mounting the output head. A pawl is slidably mounted inside the head housing. A first elastic element is provided between the head housing and the pawl. The first elastic element applies a force to the pawl in the direction of the ratchet, so that the pawl always tends to engage with the ratchet. The pawl cooperates with the ratchet to restrict the ratchet from rotating in only one direction. The transmission shaft is connected to the ratchet via a gear assembly. The output shaft of the drive motor extends into the head housing and is connected to the transmission shaft via a one-way clutch.

[0005] After adopting the above technical solution, this utility model has the following advantages: The transmission connection between the drive shaft and the ratchet is achieved using a gear assembly, eliminating the traditional eccentric push block structure, minimizing dead point problems, significantly improving operating efficiency, and making fuller use of the drive motor's output kinetic energy, thus increasing transmission torque. Simultaneously, in manual operation mode, the ratchet and slidable pawl inside the head housing maintain contact under the action of the first elastic element. When the user rotates the handle forward, the pawl engages with the ratchet teeth, driving the output head to rotate to complete the work; when the handle is rotated in the reverse direction, the pawl slides off the ratchet teeth, achieving… The relative free return between the head shell and the output head enables unidirectional drive. In electric operation mode, the drive motor is connected to the transmission shaft through a one-way clutch, allowing only unidirectional power transmission. This effectively blocks the back transmission of reverse load torque to the motor, achieving electric reverse rotation prevention. Compared with the complex double ratchet anti-reverse mechanism in the head shell of the prior art, this application only requires a mechanical ratchet assembly to achieve manual anti-reverse rotation, and works with the one-way clutch to complete electric anti-reverse rotation. This significantly simplifies the internal structure of the head shell, reduces the number of parts, and improves assembly efficiency and ease of maintenance.

[0006] Furthermore, the one-way clutch includes a first clutch element fixedly connected to one of the output shaft and the drive shaft, and a second clutch element slidably connected to the other of the output shaft and the drive shaft. The second clutch element moves relative to the first clutch element to engage or disengage with the first clutch element. The head housing is provided with a second elastic element that causes the second clutch element to have a tendency to move against the first clutch element.

[0007] By adopting the aforementioned technical solution, it is possible to achieve stable and precise power switching, and the elastic force of the second elastic element can ensure the stability of the first clutch and the second clutch when they are engaged, thereby guaranteeing the stability rate of power transmission.

[0008] Furthermore, the opposite ends of the first clutch and the second clutch are provided with one-way meshing teeth that can cooperate with each other. The one-way meshing teeth engage in the power transmission direction and slide out in the reverse direction of power transmission.

[0009] By adopting the aforementioned technical solution, the automatic engagement in the power transmission direction and the automatic disengagement in the reverse direction can be achieved without the need for additional complex sensing, control or switching mechanisms, thanks to the one-way engagement and reverse sliding characteristics of its own tooth profile.

[0010] Furthermore, the head shell is also provided with a positioning post, and the outer periphery of the drive shaft is provided with an annular groove extending in the circumferential direction. The positioning post is embedded in the annular groove to limit the axial movement of the drive shaft.

[0011] Through the above technical solution, by cooperating with the positioning column and the annular groove, the axial degree of freedom of the transmission shaft is constrained while the circumferential free rotation is not affected. This effectively restricts the axial movement of the transmission shaft, ensuring its flexible rotation during power transmission and preventing excessive movement in the axial direction. It also ensures stable meshing of the gear assembly and the cooperation between the first and second clutch components as much as possible, thereby improving the smooth operation and structural reliability of the transmission system.

[0012] Furthermore, the ratchet has a circumferentially arranged ratchet tooth surface on its outer periphery, the pawl has an arc-shaped inner side and a pawl surface that can engage with the ratchet tooth surface, and the pawl has a bent outer side and a support surface that abuts against the first elastic element.

[0013] Through the above technical solution, the ratchet teeth on the outer periphery of the ratchet are evenly arranged circumferentially, precisely matching the meshing teeth on the pawl surface, ensuring stable and reliable torque transmission during engagement. The inner side of the pawl adopts an arc-shaped design, forming a good curved surface fit with the outer periphery of the ratchet, reducing local stress concentration, improving contact strength, and reducing frictional resistance during pawl slippage, thus improving the smoothness of tooth skipping. The outer side of the pawl is provided with a bent structure and a support surface for abutting against the first elastic element, so that the force of the first elastic element can be stably applied in a predetermined direction, ensuring that the pawl always has a tendency to return to the ratchet, thereby avoiding deflection or jamming and improving the reliability of the action.

[0014] Furthermore, the head shell is provided with a sliding groove for the pawl to slide in, and the pawl is provided with a guide surface that slides in cooperation with the groove wall.

[0015] With the above technical solution, the sliding groove and the guide surface do not require additional guide components. The pawl can be accurately guided simply through the direct contact between the two. This simplifies the internal structure of the head shell, reduces the number of parts, and lowers the difficulty of processing and assembly. During operation, the sliding contact between the guide surface and the wall of the sliding groove can effectively limit the movement trajectory of the pawl, preventing the pawl from deviating or getting stuck during operation as much as possible. This ensures reliable engagement and disengagement with the ratchet and improves the stability of unidirectional transmission.

[0016] Furthermore, the guide surface and the support surface are not coplanar, so that the outer side of the pawl is bent.

[0017] By setting the guide surface and support surface to be non-coplanar, the pawl has an overall bent structure, which effectively achieves functional zoning: the guide surface cooperates with the guide structure on the head shell to ensure that the pawl's movement trajectory is accurate and does not deflect during sliding; the support surface abuts against the first elastic element to ensure that the elastic force is applied stably in the predetermined direction. The guide surface and support surface are located on different planes, making the force transmission path more reasonable and minimizing jamming or wear caused by force line eccentricity, thus improving movement flexibility and response reliability. At the same time, this bent structure facilitates the compact arrangement of the first elastic element within a limited space, improving the utilization rate of the head shell's internal space and facilitating assembly and maintenance.

[0018] Furthermore, the pawl is provided with a limiting surface facing the meshing direction with the ratchet, and the sliding groove is provided with a stop portion opposite to the limiting surface. When the pawl is engaged with the ratchet, the stop portion and the limiting surface stop each other.

[0019] By using the above technical solution, and by setting the stop surface and the stop part to cooperate, the movement position of the pawl can be precisely limited when the pawl and the ratchet are engaged, so as to prevent it from deviating due to overtravel or external impact, and ensure the stable engagement state of the pawl and the ratchet.

[0020] Furthermore, the gear assembly includes a drive gear fixedly connected to the drive shaft and a driven gear fixedly connected to the ratchet. The driven gear meshes with the drive gear, and the pawl and the driven gear are arranged vertically along the axial direction of the ratchet.

[0021] Through the above technical solution, gear transmission replaces the traditional eccentric mechanism, minimizing dead points in motion, resulting in high transmission efficiency and large output torque. Simultaneously, the pawl and driven gear are arranged vertically along the ratchet's axial direction, ensuring clear assembly, facilitating installation and maintenance, fully utilizing the axial space inside the head shell, resulting in a compact layout and rational structure. This minimizes additional circumferential space occupation, contributing to a reduction in the overall head shell size and improved structural integration.

[0022] Furthermore, the drive motor has a forward rotation direction and a reverse rotation direction, and the handle is provided with a switch to control the forward and reverse rotation of the drive motor.

[0023] Through the above technical solution, the drive motor has forward and reverse rotation directions, and the handle is equipped with a switch to control the forward and reverse rotation of the drive motor. By switching the rotation direction of the drive motor, it can be adapted to the bidirectional clutch structure of the one-way clutch, so as to realize the power output control of the tool in different directions. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings:

[0025] Figure 1 This is a partial structural diagram of the electric ratchet wrench of this utility model;

[0026] Figure 2 This is an exploded view of the electric ratchet wrench of this utility model.

[0027] Figure 3 This is a schematic diagram of the structure of the electric ratchet wrench of this utility model;

[0028] Figure 4 This is a cross-sectional view of the electric ratchet wrench of this utility model;

[0029] Figure 5 This is a partial structural cross-sectional view of the head shell of this utility model;

[0030] Figure 6 This is a schematic diagram of the structure of the transmission shaft and the second clutch of this utility model;

[0031] Figure 7 This is a schematic diagram of the structure of the first clutch and the second clutch of this utility model;

[0032] Figure 8 This is a schematic diagram of the structure of the second clutch component of this utility model;

[0033] Figure 9 This is an exploded view of the head shell of this utility model;

[0034] Figure 10 This is a partial structural diagram of the head shell of this utility model;

[0035] Figure 11 This is a schematic diagram of the pawl structure of this utility model;

[0036] Figure 12 This is a top view of the head shell of this utility model;

[0037] Figure 13 This is a schematic diagram of the head shell structure of this utility model;

[0038] In the diagram, 10 is the handle; 101 is the left housing; 102 is the right housing; 11 is the drive motor; 111 is the output shaft; 12 is the gearbox; 13 is the switch; 14 is the control board; 15 is the battery; 16 is the motor end plate; 17 is the positioning plate; 20 is the first clutch; 21 is the second clutch; 211 is the irregular hole; 2111 is the connecting section; 2112 is the stop section; 212 is the limiting hole; 213 is the limiting step; 22 is the second elastic element; 23 is the one-way meshing tooth; 231 is the protrusion; 232 is the groove; 233 is the first 1. Engagement surface; 234. Second engagement surface; 24. Stop; 30. Head shell; 31. Drive shaft; 311. Irregular shaft section; 312. Drive gear; 313. Annular groove; 32. Ratchet; 321. Insertion hole; 322. Racket tooth surface; 33. Pawl; 331. Guide surface; 332. Pawl surface; 333. Support surface; 334. Limiting surface; 34. First elastic element; 35. Sliding groove; 351. Stop; 361. Upper cover plate; 362. Lower cover plate; 37. Snap ring; 38. Driven gear; 39. Positioning pin. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.

[0040] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein.

[0041] It should be understood that in the various embodiments of this utility model, the number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this utility model.

[0042] It should be understood that in this invention, "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product or device.

[0043] It should be understood that in this utility model, "multiple" refers to two or more. "And / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, X and / or Y can represent: X alone, X and Y simultaneously, or Y alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "Contains X, Y, and Z", "Contains X, Y, and Z" means that all three X, Y, and Z are contained; "Contains X, Y, or Z" means that one of X, Y, and Z is contained; "Contains X, Y, and / or Z" means that any one, two, or three of X, Y, and Z are contained.

[0044] The technical solution of this utility model will be described in detail below with specific embodiments. The following specific embodiments can be selected to be combined or substituted with each other according to the actual situation, and the same or similar concepts or processes may not be described again in some embodiments.

[0045] like Figures 1 to 13 As shown, this utility model provides an electric ratchet wrench, including a handle 10 with a drive motor 11 and a head shell 30 with a transmission shaft 31 and an output head. A ratchet 32 ​​is rotatably mounted inside the head shell 30. The ratchet 32 ​​has a socket 321 for mounting the output head. A pawl 33 is slidably mounted inside the head shell 30. A first elastic element 34 is provided between the head shell 30 and the pawl 33. The first elastic element 34 applies a force to the pawl 33 in the direction of the ratchet 32, so that the pawl 33 always tends to engage with the ratchet 32. The pawl 33 cooperates with the ratchet 32 ​​to limit the ratchet 32 ​​to rotate only in one direction. The transmission shaft 31 is connected to the ratchet 32 ​​through a gear assembly. The output shaft 111 of the drive motor 11 extends into the head shell 30 and is connected to the transmission shaft 31 through a one-way clutch.

[0046] A gear assembly is used to achieve the transmission connection between the drive shaft 31 and the ratchet 32, eliminating the traditional eccentric push block structure, effectively avoiding dead point problems, significantly improving operating efficiency, and making fuller use of the kinetic energy output by the drive motor 11, significantly increasing the transmission torque. Meanwhile, in manual operation mode, the ratchet 32 ​​and the sliding pawl 33 inside the head shell 30 maintain contact under the action of the first elastic element 34. When the user rotates the handle 10 forward, the pawl 33 engages with the ratchet teeth of the ratchet 32, driving the output head to rotate to complete the twisting of the workpiece; when the handle 10 is rotated in the reverse direction, the pawl 33 slides off the ratchet teeth, realizing the rotation of the head shell. The relative free return between the head 30 and the output head enables manual anti-reverse rotation. In electric operation mode, the drive motor 11 is connected to the transmission shaft 31 through a one-way clutch, allowing only unidirectional power transmission, effectively blocking the back transmission of reverse load torque to the motor, and realizing the electric reverse rotation prevention function. Compared with the complex double ratchet anti-reverse mechanism set in the head shell 30 in the prior art, this application only requires a mechanical ratchet and pawl assembly to achieve manual anti-reverse rotation, and completes electric anti-reverse rotation with the one-way clutch. This significantly simplifies the internal structure of the head shell 30, reduces the number of parts, and improves assembly efficiency and convenience of later maintenance.

[0047] It should be noted that in this embodiment, the socket 321 is vertically connected, and the output head can be installed on both sides of the socket 321. When the output head is installed on the front and back sides respectively, the torque applied to the workpiece can be switched between the front and back.

[0048] The handle 10 consists of a left housing 101 and a right housing 102. The handle 10 is also equipped with a control board 14, a battery 15, a motor end plate 16, and a positioning plate 17. The control board 14 and the battery 15 are electrically connected. The output shaft 111 of the drive motor 11 is sleeved on the motor end plate 16.

[0049] The drive motor 11 has a forward and reverse rotation direction, and the handle 10 is equipped with a switch 13 to control the forward and reverse rotation of the drive motor 11. By switching the rotation direction of the drive motor 11, it can be adapted to the bidirectional clutch structure of a one-way clutch, realizing the power output control of the tool in different directions. The switch 13 is mounted on the positioning plate 17. It should be noted that in this embodiment, the drive motor 11 only needs to rotate in one direction.

[0050] The one-way clutch includes a first clutch member 20 fixedly connected to one of the output shaft 111 and the drive shaft 31, and a second clutch member 21 slidably connected to the other of the output shaft 111 and the drive shaft 31. The second clutch member 21 moves relative to the first clutch member 20 to engage or disengage with the first clutch member 20. The head housing 30 is provided with a second elastic member 22 that makes the second clutch member 21 have a tendency to move against the first clutch member 20, thereby reducing the possibility of slippage between the second clutch member 21 and the first clutch member 20 and making the power transmission more stable and reliable.

[0051] The first clutch 20 and the second clutch 21 are provided with one-way meshing teeth 23 that can cooperate with each other. The one-way meshing teeth 23 engage in the power transmission direction and slide out in the opposite direction of power transmission. Through the one-way engagement and reverse sliding characteristics of its own teeth, it can achieve automatic engagement in the power transmission direction and automatic disengagement in the opposite direction without the need for additional complex sensing, control or switching mechanisms.

[0052] In this embodiment, the first clutch 20 is fixedly connected to the output shaft 111, and the transmission shaft 31 is slidably connected to the second clutch 21. To prevent the transmission shaft 31 from slipping or misaligning during transmission, the transmission shaft 31 is provided with a shaped shaft section 311, and the second clutch 21 is provided with a shaped hole 211 that mates with the shaped shaft section 311. The shaped shaft section 311 is inserted into the shaped hole 211, ensuring that the second clutch 21 can slide axially while reliably transmitting torque and preventing circumferential slippage or misalignment during transmission, thus ensuring stable power transmission. At the same time, this structure is simple and reliable, avoiding the problems of complex structure, high processing difficulty, and inconvenient assembly caused by traditional keyed or splined connections. In addition, the fit between the shaped shaft section 311 and the shaped hole 211 also provides precise guidance for the engagement and disengagement of the one-way clutch.

[0053] The unidirectional meshing tooth portion 23 includes multiple circumferentially distributed protrusions 231 and grooves 232, with adjacent protrusions 231 forming a groove 232. The groove 232 has two inclined surfaces, a first engagement surface 233 and a second engagement surface 234, respectively. The first engagement surface 233 is inclined outwards relative to the bottom of the groove 232 (an angle greater than 90°), forming a guide ramp. The second engagement surface 234 is inclined inwards relative to the bottom of the groove 232 (an angle less than 90°), forming a load-bearing support surface. When the drive motor 11 drives the first clutch member 20 to rotate along the direction of the first engagement surface 233, the engaging protrusions 231 on the second clutch member 21 contact the ramp surface. During relative motion, a thrust is generated along the ramp, pushing the second clutch member 21 to overcome the preload of the second elastic member 22 and move axially, thus disengaging and entering an idle state.

[0054] When the drive motor 11 drives the first clutch 20 to rotate along the direction of the second clutch surface 234, the mating protrusion 231 on the second clutch 21 quickly slides into the groove 232 and forms a surface contact with the second clutch surface 234. At this time, the two tooth surfaces are wedged together, the torque is reliably transmitted, and the power engagement is achieved.

[0055] Of course, it is understandable that in other embodiments, the second clutch 21 may also be slidably connected to the output shaft 111, the first clutch 20 may be fixedly connected to the transmission shaft 31, and the second elastic member 22 may act on the second clutch 21 to make the first clutch 20 have a tendency to move against the second clutch 21, and the teeth of the two mesh to restrict the second clutch 21 from disengaging from the output shaft 111.

[0056] Among them, the irregular shaft section 311 is axially spaced with a stop 24 and a second elastic member 22, and the second clutch 21 is disposed between the stop 24 and the second elastic member 22. The second elastic member 22 provides a continuous reset force for the second clutch 21, so that it automatically resets to the preset position when no external force is applied, ensuring stable engagement with the first clutch 20. The stop 24 plays an axial limiting role, preventing the second clutch 21 from disengaging during sliding, thereby improving the safety and reliability of the structure.

[0057] It should be noted that the cross-section of the irregular hole 211 includes a connecting section 2111 for guiding and a stop section 2112 for preventing rotation. The connecting section 2111 is circular and the stop section 2112 is straight. The transmission shaft 31 is provided with a structure of the same shape.

[0058] It should be noted that the second clutch 21 is provided with a limiting hole 212 communicating with the irregular hole 211. The limiting hole 212 is located at the end of the irregular hole 211 away from the second elastic member 22, and its diameter is larger than that of the irregular hole 211, thereby forming a limiting step 213 at the connection. The stop member 24 is set in the limiting hole 212 to achieve concealed installation, which helps to reduce the overall structural space and improve the layout compactness. At the same time, the tooth surface structure is arranged in a ring on the outer periphery of the limiting hole 212 of the second clutch 21. The second elastic member 22 can be a compression spring sleeved on the irregular shaft, and the stop member 24 can be a retaining spring.

[0059] It should be noted that the output shaft 111 of the drive motor 11 is connected to the gearbox 12. The output shaft 111 of the drive motor 11 is fixedly connected to the first clutch 20 through the gearbox 12. The gearbox 12 increases the output torque of the drive motor 11 by setting a small gear to drive a large gear.

[0060] Specifically, the head shell 30 is equipped with a positioning post 39. The outer circumference of the drive shaft 31 has an annular groove 313 extending circumferentially. The positioning post 39 is embedded in the annular groove 313 to restrict the axial movement of the drive shaft 31. While ensuring unaffected circumferential rotation, only the axial degree of freedom of the drive shaft 31 is constrained, effectively limiting its axial movement. This ensures flexible rotation of the drive shaft 31 during power transmission while preventing excessive axial movement. It also maximizes the stability of the gear assembly meshing and the coordination between the first clutch 20 and the second clutch 21, improving the smooth operation and structural reliability of the transmission system.

[0061] The other end of the drive shaft 31 is provided with a driving gear 312, and the ratchet 32 ​​is provided with a driven gear 38 that cooperates with the driving gear 312. The driven gear 38 and the driving gear 312 form a gear assembly between the drive shaft 31 and the ratchet 32. The driven gear 38 and the driving gear 312 are connected by a spline. Due to the setting of the first clutch 20 and the second clutch 21, the torque rotation direction of the drive shaft 31 is only in one direction. When electrically driven, the ratchet 32 ​​can only rotate in one direction. In order to achieve torque output in different directions, the torque can be switched by flipping the electric ratchet wrench. Among them, the driving gear 312 is a bevel gear, and the driving gear 312 is integrally formed with the drive shaft 31. The driven gear 38 is a gear ring.

[0062] The ratchet 32 ​​has a circumferentially arranged ratchet tooth surface 322 on its outer periphery. The inner side of the pawl 33 is arc-shaped and has a pawl surface 332 that can mesh with the ratchet tooth surface 322, so that it forms a good curved surface fit with the outer periphery of the ratchet 32, reducing local stress concentration and improving contact strength. At the same time, it reduces frictional resistance during the slippage of the pawl 33 and improves the smoothness of the tooth skipping. The outer side of the pawl 33 is bent and has a support surface 333 that abuts against the first elastic member 34, so that the force of the first elastic member 34 can be stably applied in a predetermined direction, ensuring that the pawl 33 always has a tendency to return to the ratchet 32, thereby avoiding deflection or jamming as much as possible and improving the reliability of the action.

[0063] The head housing 30 is provided with a sliding groove 35 for the pawl 33 to slide. The pawl 33 is provided with a guide surface 331 that slides and engages with the groove wall of the sliding groove 35. No additional guide components are required. The pawl 33 can be precisely guided simply through the direct contact between the two. This simplifies the internal structure of the head housing 30, reduces the number of parts, and lowers the difficulty of processing and assembly. During operation, the sliding contact between the guide surface 331 and the groove wall of the sliding groove 35 can effectively limit the movement trajectory of the pawl 33 and prevent the pawl 33 from deviating or getting stuck during operation. This ensures reliable engagement and disengagement with the ratchet 32 ​​and improves the stability of unidirectional transmission.

[0064] In this design, the guide surface 331 and the support surface 333 are not coplanar, causing the outer side of the pawl 33 to be bent. This effectively achieves functional zoning: the guide surface 331 cooperates with the guide structure on the head shell 30 to ensure that the pawl 33 moves accurately and without deflection during sliding; the support surface 333 abuts against the first elastic element 34 to ensure that the elastic force is applied stably in the predetermined direction. The guide surface 331 and the support surface 333 are located on different planes, making the force transmission path more rational and minimizing jamming or wear caused by force line eccentricity, thus improving movement flexibility and response reliability. Simultaneously, this bent structure facilitates a compact arrangement of the elastic element within a limited space, improving the utilization rate of the internal space of the head shell 30 and facilitating assembly and maintenance.

[0065] The pawl 33 has a limiting surface 334 facing the meshing direction with the ratchet 32, and the sliding groove 35 has a stop part 351 opposite to the limiting surface 334. When the pawl 33 is engaged with the ratchet 32, the stop part 351 and the limiting surface 334 stop and cooperate to prevent it from deviating due to overtravel or external impact, and ensure the stable meshing state of the pawl 33 and the ratchet 32.

[0066] It should be noted that the pawl 33 and the driven gear 38 are arranged vertically along the axial direction of the ratchet 32, separated from each other, with clear assembly, which facilitates installation and maintenance. It makes full use of the axial space inside the head shell 30, with a compact layout and reasonable structure, and avoids additional occupation of circumferential space as much as possible. This helps to reduce the overall size of the head shell 30 and improve the structural integration. The top of the pawl 33 is provided with an upper cover plate 361 for limiting, and the bottom of the pawl 33 is supported on the bottom surface of the sliding groove 35. The bottom of the gear ring is provided with a retaining ring 37 and a lower cover plate 362 for limiting.

[0067] It should be noted that the first elastic element 34 is a spring sheet, which can be wavy. Wavy spring sheets have good elastic deformation capability and reset performance, which can provide a continuous and stable elastic force for the pawl 33, ensuring that the pawl 33 always tends to engage with the ratchet 32. Compared with traditional elastic elements such as helical springs, the spring sheet structure is flatter, which helps to reduce the space occupied inside the head shell 30 and make the overall structure more compact. At the same time, the spring sheet is easy to process and assemble, which can effectively reduce manufacturing costs and assembly difficulty. In addition, the wavy structure has multi-point support and buffering effect when subjected to force, which can effectively absorb vibration and impact, and improve the stability and service life of the ratchet 32 ​​assembly in the process of frequent engagement and disengagement.

[0068] Of course, in other embodiments, the spring can also be a V-shaped, U-shaped, arched or other structural form with elastic deformation capability. Springs of different shapes can be flexibly selected according to the actual spatial layout, assembly method and elasticity requirements, which further improves the adaptability of structural design and process flexibility.

[0069] In this embodiment, there are two pawls 33, which are symmetrically arranged in the axial direction of the ratchet 32. Working together can improve the reliability of one-way locking and distribute the torque transmitted by the ratchet 32 ​​to different positions, so as to avoid wear or deformation of a single pawl 33 due to excessive force.

[0070] In this embodiment, the electric ratchet wrench has two operating modes: electric drive and manual drive. When the electric ratchet wrench is in electric drive mode, after the output head is installed in the socket 321, the user controls the drive motor 11 to turn on by pressing the switch 13. The drive motor 11 drives the output shaft 111 to rotate. At this time, the one-way meshing teeth 23 of the first clutch 20 and the one-way meshing teeth 23 of the second clutch 21 engage. The power of the output shaft 111 drives the ratchet 32 ​​to rotate relative to the head shell 30 through the transmission shaft 31. The ratchet tooth surface 322 of the ratchet 32 ​​drives the pawl 33 to move in the direction of compressing the spring. The pawl 33 disengages from the ratchet 32, and the output head rotates synchronously with the ratchet 32 ​​to tighten the workpiece. To loosen the workpiece, simply reverse the direction of the electric ratchet wrench and insert the output head into the socket 321 in the opposite direction. At this time, the output head drives the workpiece to rotate in the opposite direction, thereby loosening the workpiece.

[0071] When the electric ratchet wrench is in manual drive mode, the drive motor 11 is not started. The user manually controls the handle 10 to rotate the workpiece. In the direction of rotation of the handle 10, the ratchet 32 ​​and the pawl 33 engage and limit the ratchet 32 ​​to keep the head shell 30 relatively fixed. Therefore, the user can rotate the handle 10 to rotate the workpiece. Manual drive can make the installation of the workpiece more compact and can also loosen jammed workpieces, avoiding the possibility of damage to the drive motor 11 due to excessive load. During manual drive, after the user rotates the handle 10 to a certain angle, in order to make it easier for the user to apply force, the user can rotate the handle 10 in the opposite direction. In the direction of rotation of the handle 10, the ratchet 32 ​​and the pawl 33 form a sliding engagement, and the ratchet 32 ​​and the head shell 30 can rotate relative to each other. The ratchet 32 ​​will drive the transmission shaft 31 to rotate in the opposite direction. At this time, the one-way meshing teeth 23 of the first clutch 20 and the one-way meshing teeth 23 of the second clutch 21 disengage and will not drive the drive motor 11 to rotate. During manual driving, the reversing function can also be achieved by changing the installation direction of the output head.

[0072] Understandably, in other embodiments, only one pawl may be provided, resulting in the simplest structure and convenient assembly. Of course, three, four, or other pawls may also be provided, with multiple pawls working together to improve the reliability of unidirectional locking.

[0073] In addition to the preferred embodiments described above, there are other embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection claimed by this utility model.

Claims

1. An electric ratchet wrench comprising a handle (10) provided with a driving motor (11) and a head case (30) provided with a transmission shaft (31) and an output head, characterized in that, A ratchet (32) is rotatably mounted inside the head shell (30). The ratchet (32) has a socket (321) for mounting an output head. A pawl (33) is slidably mounted inside the head shell (30). A first elastic element (34) is provided between the head shell (30) and the pawl (33). The first elastic element (34) applies a force to the pawl (33) in the direction of the ratchet (32), so that the pawl (33) always tends to engage with the ratchet (32). The pawl (33) cooperates with the ratchet (32) to restrict the ratchet (32) from rotating in only one direction. The drive shaft (31) is connected to the ratchet (32) through a gear assembly. The output shaft (111) of the drive motor (11) extends toward the head shell (30) and is connected to the drive shaft (31) through a one-way clutch.

2. The electrically powered ratchet wrench of claim 1, wherein The one-way clutch includes a first clutch member (20) fixedly connected to one of the output shaft (111) and the drive shaft (31), and a second clutch member (21) slidably connected to the other of the output shaft (111) and the drive shaft (31). The second clutch member (21) moves relative to the first clutch member (20) to engage or disengage with the first clutch member (20). The head shell (30) is provided with a second elastic member (22) that causes the second clutch member (21) to have a tendency to move against the first clutch member (20).

3. The electrically powered ratchet wrench of claim 2, wherein The first clutch (20) and the second clutch (21) are provided with one-way meshing teeth (23) that can cooperate with each other. The one-way meshing teeth (23) engage in the power transmission direction and slide out in the opposite direction of power transmission.

4. The electrically powered ratchet wrench of claim 1, wherein The head shell (30) is also provided with a positioning post (39), and the outer periphery of the drive shaft (31) is provided with an annular groove (313) extending in the circumferential direction. The positioning post (39) is embedded in the annular groove (313) to limit the axial movement of the drive shaft (31).

5. The electrically powered ratchet wrench of claim 1, wherein, The ratchet (32) has a circumferentially arranged ratchet tooth surface (322) on its outer periphery. The inner side of the pawl (33) is arc-shaped and has a pawl surface (332) that can mesh with the ratchet tooth surface (322). The outer side of the pawl (33) is bent and has a support surface (333) that abuts against the first elastic member (34).

6. The electrically powered ratchet wrench of claim 5, wherein, The head shell (30) is provided with a sliding groove (35) for the pawl (33) to slide, and the outer side of the pawl (33) is also provided with a guide surface (331) that slides in cooperation with the groove wall of the sliding groove (35).

7. The electrically powered ratchet wrench of claim 6, wherein, The guide surface (331) and the support surface (333) are not coplanar so that the outer side of the pawl (33) is bent.

8. The electrically powered ratchet wrench of claim 6, wherein, The pawl (33) has a limiting surface (334) facing the meshing direction with the ratchet (32), and the sliding groove (35) has a stop part (351) opposite to the limiting surface (334). When the pawl (33) is engaged with the ratchet (32), the stop part (351) and the limiting surface (334) stop and cooperate.

9. The electrically powered ratchet wrench of claim 1, wherein, The gear assembly comprises a driving gear (312) fixedly connected with a transmission shaft (31), and a driven gear (38) fixedly connected with a ratchet wheel (32), the driven gear (38) is engaged with the driving gear (312), and the pawl (33) and the driven gear (38) are arranged up and down along the axial direction of the ratchet wheel (32).

10. The electrically powered ratchet wrench of claim 1, wherein, The driving motor (11) has a forward rotation direction and a reverse rotation direction, and the handle (10) is provided with a switch (13) for controlling the forward and reverse rotation of the driving motor (11).

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