Power tool

Abstract

The application discloses an electric tool, which comprises a casing, a gear box accommodated in the casing, a transmission assembly arranged in the gear box, a sliding groove penetrating from an outer surface to an inner surface of a side wall of the gear box, and a gear shifting mechanism comprising a gear shifting steel wire connected with the transmission assembly and extending to outside of the gear box through the sliding groove. When the gear shifting steel wire moves forward and backward along the sliding groove, the transmission assembly performs gear shifting. The sliding groove comprises a sliding part and limiting parts arranged at two ends of the sliding part. The gear shifting steel wire moves along the sliding part and is limited by the limiting parts at any one of the limiting parts.

Description

Technical Field

[0001] This application relates to the field of power tools, and more particularly to power tools with a shift mechanism. Background Technology

[0002] With the continuous development of power tools, they have become adaptable to different scenarios. For example, gun drills are widely used in industries such as construction, decoration, and furniture because they are convenient to carry and use when drilling. Early gun drills only had a single speed setting, which could not meet the needs of different drilling environments. Therefore, more and more gun drills have speed adjustment functions. Existing gun drills use a shift knob on the tool to transmit the movement of the shift wire to switch gears. However, because the shift wire is made of a soft material and is easily deformed, it is prone to slipping during gear switching, causing the tool to not stay in one gear. Therefore, it is necessary to have a separate structure to limit the shift wire when it is moved to the corresponding position. The most common limiting structure is to set a limiting protrusion on the gearbox housing, located outside the slide groove. However, this limiting structure has some problems: First, the slide groove mainly provides guidance for the movement of the shift wire. When the shift wire is shifting gears, it not only needs to move along the slide groove, but also needs to overcome the obstruction of the limiting protrusion, moving radially in the gearbox, resulting in poor stability of the shift wire movement. Second, as the shift wire moves radially, the grease inside the gearbox will continuously leak out, affecting the user experience. Summary of the Invention

[0003] One object of the present invention is to provide a power tool that can achieve both a limiting effect and improve the stability of the tool during operation.

[0004] This invention provides an electric tool, comprising: a housing; a gearbox housed within the housing, the gearbox having a transmission assembly inside, and a groove extending from the outer surface to the inner surface of the side wall of the gearbox; a shifting mechanism including a shift wire connected to the transmission assembly and extending through the groove to the outside of the gearbox, wherein the transmission assembly performs gear shifting when the shift wire moves back and forth along the groove; the groove having a sliding portion and limiting portions located at both ends of the sliding portion, the shift wire moving along the sliding portion and being limited when located at either of the limiting portions.

[0005] A further improvement is that the sliding part is located on the upper side of the inner wall of the groove, making the groove concave.

[0006] A further improvement is as follows: the shifting mechanism further includes a shifting pusher and a shifting gear ring, wherein the shifting pusher is movably mounted on the housing.

[0007] A further improvement is as follows: the middle part of the shift wire is connected to the shift push knob, and the middle part of the shift wire extends to either side with a pivot ring, a limiting leg and a connecting end. The shift wire is connected to the outer wall of the gearbox through the pivot ring and can be pushed by the shift push knob to rotate around the gearbox. The connecting end of the shift wire extends into the slide groove and is connected to the shift gear ring.

[0008] A further improvement is as follows: when the shifting push torque drives the shifting wire to rotate and positions the limiting leg at any of the limiting parts, the gear position of the transmission component is maintained.

[0009] A further improvement is that the shift wire surrounds the outer wall of the gearbox in a partially circular manner and is oscillatingly supported on the outer wall of the gearbox.

[0010] A further improvement is that the shifting assembly also includes a limiting ring, and the shifting gear ring can engage or disengage with the limiting ring by moving back and forth.

[0011] A further improvement is as follows: the shift lever moves backward, and the corresponding limiting leg of the shift wire swings forward to drive the shift gear ring to move forward and engage with the limiting ring. At this time, the speed ratio of the transmission component increases, and the power tool outputs at a low speed in first gear.

[0012] A further improvement is as follows: the shift knob moves forward, and the corresponding limiting leg of the shift wire swings backward to drive the shift gear ring to move backward and disengage from the limiting ring. At this time, the speed ratio of the transmission component becomes smaller, and the power tool outputs at high speed in second gear.

[0013] A further improvement is that the power tool also includes a torque adjustment component and a mode switching component.

[0014] Compared with the prior art, the beneficial effects of this application are: the limiting part is set on the inner wall of the slide groove, and when the shifting mechanism shifts gears, it only needs to move along the slide groove and will not move in the radial direction of the gearbox, so the movement stability is better. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a power tool according to an embodiment of this application; Figure 2 This is a partial cross-sectional view of a power tool according to an embodiment of this application; Figure 3 This is an exploded view of a portion of the structure of a power tool according to an embodiment of this application; Figure 4 This is a schematic diagram of the structure of the shift assembly according to an embodiment of this application; Figure 5 yes Figure 4 A schematic diagram of the shift assembly in first gear; Figure 6 yes Figure 4 A schematic diagram of the shift assembly in second gear; Figure 7 yes Figure 4 A schematic diagram of the chute structure.

[0016] Meaning of the reference numerals in the diagram: Detailed Implementation

[0017] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0018] In the description of this application, it should be noted that the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., which indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and should not be construed as limiting the specific protection scope of this application.

[0019] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0020] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application 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.

[0021] Reference Figures 1 to 7In this embodiment, the power tool is preferably an impact drill. The impact drill includes a housing 1, which includes a left housing and a right housing that are fitted together. A torque adjustment component 2 and a mode switching component 3 are fitted at the front end of the housing 1. A gearbox 4, a shifting component 5, and an impact component 6 are housed in the middle of the housing 1. A grip portion 7 extends downward from the middle of the housing 1 for the user to hold the impact drill during operation. The grip portion 7 is equipped with a switch for the user to operate and control the start and stop of the impact drill. The lower end of the grip portion 7 can be used to connect a battery pack, which supplies power to the impact drill. A motor 8 is housed at the rear end of the housing 1.

[0022] Gearbox The gearbox 4 is housed within the housing 1 and includes a first gearbox housing 41, a second gearbox housing 42, and an output shaft 43 supporting the first and second gearbox housings 42. The output shaft 43 has a protrusion. The gearbox 4 has a transmission assembly 44 inside, which includes a planetary gear train mechanism. The outer wall of the gearbox 4 has a sliding groove 421.

[0023] Furthermore, the first gearbox housing 41 includes a base 411 and a cylindrical protrusion 412. The base 411 includes an end face, and the cylindrical protrusion 412 protrudes from the end face of the base 411. The cylindrical protrusion 412 has a through hole 4121 penetrating the base 411. The first gearbox housing 41 also includes a first limiting part 413 and a second limiting part 414 between the base 411 and the cylindrical protrusion 412.

[0024] Preferably, the first limiting part 413 is an annular groove and the second limiting part 414 is a vertical groove.

[0025] Furthermore, the seat 411 has a plurality of cylindrical holes 4111 that penetrate the end face and are distributed around the cylindrical protrusion 412. The cylindrical holes 4111 are used to set a pin, which can move within the cylindrical holes 4111.

[0026] Furthermore, the second gearbox housing 42 has a groove 421 extending from the outer surface to the inner surface on its side wall. The groove 421 is used for the shifting assembly 5 to extend into the gearbox 4 to perform gear switching.

[0027] Preferably, the slide groove 421 is arc-shaped, and the arc-shaped slide groove 421 can facilitate the smooth forward and backward sliding of the shifting element.

[0028] Furthermore, the slide groove has a sliding part 4211 and a limiting part 4212 located at both ends of the sliding part. The sliding part 4211 is disposed on the upper side of the inner wall of the slide groove 421, so that the slide groove 421 is in the shape of a "U".

[0029]

Shift Components

[0030] Furthermore, the shift wire 52 surrounds the second gearbox housing 42 in a partially circular manner and is oscillatingly supported on the second gearbox housing 42 by the arc-shaped groove 421.

[0031] Preferably, the shift wire 52 surrounds the second gearbox housing 42 in a semi-circular manner.

[0032] Furthermore, the shift assembly 5 also includes a limiting ring 54, and the shift push torque 51 moves back and forth to cause the shift wire 52 to swing left and right to realize the engagement and disengagement of the shift gear ring 53 and the limiting ring 54.

[0033] In this embodiment, the gear switching principle of the impact drill is as follows: when the user moves the shift push knob 51 backward, the limiting leg 522 of the shift wire 52 swings forward to drive the shift gear ring 53 to move forward and engage with the limiting ring 54. At this time, the speed ratio of the transmission component 44 increases, and the power tool outputs high torque at a low speed in first gear, which is suitable for drilling holes in objects with low hardness such as wooden boards. When the user moves the shift knob 51 forward, the limiting leg 522 of the shift wire 52 swings backward to drive the shift gear ring 53 to move backward and disengage from the limiting ring 54. The power tool outputs high speed and low torque in second gear, which is suitable for drilling hard objects such as iron plates.

[0034] [Impact Component] The impact assembly 6 includes a static impact ratchet 61, a dynamic impact ratchet 62, a switching seat 63, a bearing, and a spring. The static impact ratchet 61 is fixed to the inner wall of the through hole of the first gearbox housing 41. The dynamic impact ratchet 62 is fixedly sleeved on the output shaft 43 and is located between the static impact ratchet 61 and the switching seat 63. The spring is located between the protrusion of the output shaft 43 and the static impact ratchet 61.

[0035] Furthermore, the static impact ratchet 61 includes at least one protrusion 611, which is stepped.

[0036] The switching seat 63 is disposed in the through hole 4121. The switching seat 63 includes an axially extending convex arm 631 and an extension arm 632 that connects to the convex arm 631 and extends radially. The extension arm 632 can move between abutting the convex post 611 and a position away from the convex post 611.

[0037] During the movement of the moving impact ratchet 62 relative to the static impact ratchet 61, the moving impact ratchet 62 drives the output shaft 43 to perform impact reciprocating motion in the axial direction of the output shaft 43.

[0038] [Electric motor] The motor 8 includes a rotor, a stator, and a motor shaft 81 supporting the rotor and stator. The motor shaft 81 is connected to the rear end of the planetary gear train mechanism, and the output shaft 43 is connected to the front end of the planetary gear train mechanism. The motor shaft 81 extends forward into the gearbox 4 and meshes with the planetary gear train mechanism, thereby driving the planetary gear train mechanism to operate.

[0039] Preferably, the motor 8 is a DC brushless motor.

[0040] Torque Adjustment Component The torque adjustment assembly 2 includes a torque cup 21, a force ring 22, and a clicker 23. The torque cup 21 is used by the user to rotate it to set different torques. The front end of the torque cup is also provided with a chuck for holding tool accessories. The torque cup 21 includes an internal thread and multiple positioning grooves, which are located on the inner ring surface of the torque cup 21. The force ring 22 includes an external thread, which engages with the internal thread of the torque cup 21. During the user's rotation of the torque cup 21, the clicker 23 engages with the positioning grooves and makes a "click" sound to remind the user to pay attention to the current torque.

[0041] [Mode Switching Component] The mode switching component 3 includes a mode switching cover 31, an operating component 32, and an elastic component 33. The mode switching cover 31 is used for the user to rotate and select any one of the drilling mode, impact mode, and screw driving mode.

[0042] The operating component 32 includes a gasket 321, a switching ring 322, and a retaining ring 323. The gasket 321 has an arc-shaped protrusion 3211 on its inner circumference, which engages with the vertical groove to abut against the pin. The switching ring 322 is sleeved on the gasket 321 and includes a positioning part 3221 and a fixing groove 3222. The retaining ring 323 has a pressure plate 3231 on its side, which is used to press the switching ring 322. The retaining ring 323 has multiple protrusions on its upper surface, which abut against the elastic member 33.

[0043] Furthermore, the positioning part 3221 is in the shape of a protrusion and protrudes from the outer circumference of the switching ring 322. The fixing groove 3222 is provided on the inner circumferential surface of the switching ring 322. The switching ring 322 can rotate to the first position, the second position and the third position according to the axis of the first gearbox housing 41.

[0044] Furthermore, the inner wall of the mode switching cover 31 also includes a groove, which is used to engage with the positioning part 3221 of the switching ring 322, so that the mode switching cover 31 can drive the switching ring 322 to rotate during rotation. When the switching ring 322 rotates to the first position, the fixing groove 3222 of the switching ring 322 engages with the annular groove on the first gearbox housing 41, restricting the axial movement of the gasket 321 and the retaining ring 323. When the switching ring 322 rotates to the second or third position, the fixing groove 3222 of the switching ring 322 is misaligned with the annular groove on the first gearbox housing 41, allowing the axial movement of the gasket 321, the switching ring 322, and the retaining ring 323.

[0045] Furthermore, the first position corresponds to the screw-driving mode of the power tool, and the second and third positions correspond to the drilling mode and impact mode of the power tool, respectively.

[0046] In one embodiment of this application, an electric tool is provided. The gearbox 4 of the electric tool has a groove 421 extending from the outer surface to the inner surface on its side wall. The groove 421 has a sliding part 4211 and a limiting part 4212 located at both ends of the sliding part. The shift wire 52 moves along the sliding part 4211 and is limited when it is located at any of the limiting parts 4212. According to the solution of this application, when the user switches gears on the power tool, the shift lever moves backward, and the limiting leg of the shift wire slides forward along the sliding part of the slide groove, while driving the shift gear ring to move forward and engage with the limiting ring. The limiting leg is positioned at the limiting part at the left end of the sliding part. At this time, the speed ratio of the transmission component increases, and the power tool maintains a low-speed output in first gear. As the shift knob moves forward, the corresponding limiting leg of the shift wire slides backward along the sliding part of the slide groove, simultaneously driving the shift gear ring to move backward and disengage from the limiting ring. The limiting leg is positioned at the limiting part on the right end of the sliding part. At this time, the speed ratio of the transmission component decreases, and the power tool maintains high-speed output in second gear.

[0047] By setting a limiting part on the inner wall of the slide, the shifting mechanism only needs to move along the slide when shifting gears, and will not move in the radial direction of the gearbox, thus achieving good stability of movement.

[0048] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. An electric tool, comprising: chassis; A gearbox is housed within the housing, the gearbox having a transmission assembly inside, and a groove extending from the outer surface to the inner surface on the side wall of the gearbox. The shifting mechanism includes a shifting wire connected to the transmission assembly and extending through the slide groove to the outside of the gearbox. When the shifting wire moves back and forth along the slide groove, the transmission assembly performs gear switching. The feature is that the slide groove has a sliding part and a limiting part located at both ends of the sliding part, the shifting wire moves along the sliding part, and the shifting wire is limited when it is located at any of the limiting parts.

2. The power tool according to claim 1, characterized in that, The sliding part is located on the upper side of the inner wall of the groove, making the groove concave.

3. The power tool according to claim 2, characterized in that, The shifting mechanism also includes a shifting pusher and a shifting gear ring, wherein the shifting pusher is movably mounted on the housing.

4. The power tool according to claim 3, characterized in that, The middle part of the shift wire is connected to the shift push knob. The middle part of the shift wire extends to either side and has a pivot ring, a limiting leg, and a connecting end. The shift wire is connected to the outer wall of the gearbox through the pivot ring and can be pushed by the shift push knob to rotate around the gearbox. The connecting end of the shift wire extends into the slide groove and is connected to the shift gear ring.

5. The power tool according to claim 4, characterized in that, When the shifting push torque drives the shifting wire to rotate and positions the limiting leg at any of the limiting parts, the gear position of the transmission assembly is maintained.

6. The power tool according to claim 5, characterized in that, The shift wire surrounds the outer wall of the gearbox in a partially circular manner and is oscillatingly supported on the outer wall of the gearbox.

7. The power tool according to claim 6, characterized in that, The shifting assembly also includes a limiting ring, and the shifting gear ring can engage or disengage with the limiting ring by moving back and forth.

8. The power tool according to claim 7, characterized in that, When the shift lever moves backward, the corresponding limiting leg of the shift wire swings forward to drive the shift gear ring to move forward and engage with the limiting ring. At this time, the speed ratio of the transmission component increases, and the power tool outputs at a low speed in first gear.

9. The power tool according to claim 8, characterized in that, As the shift knob moves forward, the corresponding limiting leg of the shift wire swings backward to drive the shift gear ring to move backward and disengage from the limiting ring. At this time, the speed ratio of the transmission component decreases, and the power tool outputs at high speed in second gear.

10. The power tool according to claim 1, characterized in that, The power tool also includes a torque adjustment component and a mode switching component.

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