A handheld power tool

Abstract

The present invention discloses a handheld power tool, which includes: a housing, a motor, an operating member, an output shaft, and a transmission mechanism with a speed gear ring, wherein the speed gear ring can move between a first switching position and a second switching position. The electric drill also includes an elastic member and a stopper arranged on the housing, wherein the stopper can abut against the elastic member to prevent the elastic member from driving the speed gear ring to move between the first and second switching positions; when the external force applied to the elastic member by the operator through the operating member is greater than the elastic force of the elastic member itself, the elastic member can be elastically deformed to overcome the stopping effect of the stopper on it, thereby driving the speed gear ring to move from one of the first and second switching positions to the other of the two; when the external force applied to the elastic member is less than the elastic force of the elastic member itself, the elastic member abuts against the stopper to prevent the speed gear ring from switching from one of the first and second switching positions to the other of the two. The abutment of the elastic member and the stopper makes the structure of the whole machine simpler.

Description

Technical Field

[0001] The present invention relates to the technical field of electric tools, and in particular to a handheld power tool. Background Art

[0002] In the related art, a handheld power tool (eg, an electric drill) generally has at least two gears. When switching between the two gears, a shift wire needs to be pushed by a push button to switch the gears.

[0003] Furthermore, the shift wire needs to remain stationary at a certain gear position so that the handheld power tool can work continuously and stably at the gear position. However, the existing handheld power tool needs to be provided with a stop elastic member so that the shift wire can remain stationary at a certain gear position. This results in a complex structure of the shift assembly, a large number of parts, difficulty in safety and high cost. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a handheld power tool with a simple structure.

[0005] A handheld power tool comprises: a motor for outputting rotational power; a housing for accommodating the motor; an operating member operably arranged relative to the housing; an output shaft for matching a tool head; a transmission mechanism comprising a speed gear ring, the speed gear ring being movable between a first switching position and a second switching position so that the transmission mechanism can transmit the rotation speed of the motor to the output shaft at different transmission ratios; and an elastic member, which is transmission-connected between the operating member and the speed gear ring; the handheld power tool further comprises a stopper arranged on the housing, the stopper being able to abut against the elastic member to prevent the elastic member from driving the speed gear ring to switch freely between the first switching position and the second switching position; when the external force applied to the elastic member by the operator through the operating member is greater than the elastic force of the elastic member itself, the elastic member can be elastically deformed to overcome the stopping effect of the stopper on it, thereby being able to drive the speed gear ring to move from one of the first and second switching positions to the other of the two; when the external force applied to the elastic member is less than the elastic force of the elastic member itself, the elastic member abuts against the stopper to prevent the speed gear ring from switching from one of the first and second switching positions to the other of the two.

[0006] Preferably, the elastic member comprises a steel wire, the steel wire comprises a free end for mating with the speed change gear ring, and the two free ends of the steel wire are arranged on both sides of the axis of the output shaft.

[0007] Preferably, the elastic member drives the speed change gear ring to move axially along the output shaft between a first switching position and a second switching position under the action of the operating member.

[0008] Preferably, the housing includes a gear box housing wrapped around the outer periphery of the transmission mechanism and a main body covering at least a portion of the motor and the gear box housing.

[0009] Preferably, the main body is provided with a notch, and one of the main body and the operating member is provided with a guide rail, and the other of the two is provided with a guide groove, so that the operating member can be slidably disposed in the notch.

[0010] Preferably, the operating member includes an operating plate at least partially exposed in the notch, and the main body also includes a base plate located between the operating plate and the gear box housing, and the operating plate is slidably supported on the base plate.

[0011] Preferably, the operating member further comprises a clamping portion fixed to the operating plate and used for clamping the elastic member, the clamping portion comprises a first clamping plate and a second clamping plate, and the first and second clamping plates are respectively located on both sides of the elastic member along the output axis.

[0012] Preferably, the operating member further comprises a clamping portion fixed to the operating plate and used for clamping the elastic member, the clamping portion is provided with a stop groove extending in the axial direction, and the base plate extends into the stop groove.

[0013] Preferably, the operating member also includes a clamping portion fixed to the operating plate and used to clamp the steel wire, the clamping portion is provided with a stop groove extending axially, the stop member is arranged on the base plate and extends to the stop groove, the elastic member is exposed in the stop groove and can abut against the stop member.

[0014] Preferably, the elastic member is integrally formed of a steel wire, the steel wire comprises free ends located on both sides of the output shaft axis for mating with the speed gear ring, and the steel wire is symmetrically arranged relative to the output shaft axis.

[0015] Preferably, the area of ​​the operating plate is larger than the area of ​​the notch.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0018] Figure 1 is a three-dimensional schematic diagram of an electric drill according to an embodiment of the present invention;

[0019] Figure 2 is a schematic diagram of a partial cross section of an electric drill according to an embodiment of the present invention;

[0020] Figure 3 yes Figure 2 A schematic diagram of the transmission mechanism without part of the gear box housing, and a schematic diagram of the steel wire moving to another position under the action of the operating member;

[0021] Figure 4 is another partial cross-sectional schematic diagram of an electric drill according to an embodiment of the present invention;

[0022] Figure 5 is a schematic diagram of an electric drill according to an embodiment of the present invention with half of the main housing removed;

[0023] Figure 6 yes Figure 3 Enlarged view of point A in the middle;

[0024] Figure 7 It is a schematic diagram of the structure of the steel wire;

[0025] Figure 8 It is a structural schematic diagram of the operating part;

[0026] Fig. 9 It is a schematic diagram of the structure of the operating part and the steel wire;

[0027] Fig.10 yes Figure 5 Partial cross-sectional view along line A2-A2. DETAILED DESCRIPTION

[0028] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0029] See also Figure 1-Figure 5 A handheld power tool is specifically described by taking an electric drill 100 as an example. The handheld power tool comprises a housing 10 and a motor 20 disposed in the housing 10. The motor 20 is used to output rotational power.

[0030] The handheld power tool also includes an output shaft 3 for receiving a tool head and a transmission mechanism 40, the transmission mechanism 40 can transmit the rotational power of the motor 20 to the output shaft 3, and a chuck (not shown in the figure) is connected to the output shaft 3. The electric drill 100 also includes a battery pack 80 for providing energy. Preferably, the housing 10 includes a gear box housing 101 coated on the outer periphery of the transmission mechanism 40 and a half-shaped main housing 102 covering at least a portion of the motor 20 and the gear box housing 101. The main housing 102 includes a main body 1020 extending axially along the output shaft 3 and covering at least a portion of the motor 20 and the gear box housing 101, and a handle 1021 arranged at an angle to the main body 1020.

[0031] Preferably, the transmission mechanism 40 in this embodiment is a three-stage transmission planetary gear train, and the first-stage planetary gear train includes a primary sun gear (not shown in the figure) located on the driving shaft 21 of the motor 20, a plurality of primary planetary gears (not shown in the figure) meshing with the primary sun gear, a primary inner gear ring 411 fixedly arranged relative to the housing and meshing with the primary planetary gears, and a primary planet carrier (not shown in the figure) driven to rotate by the primary planetary gears. The second-stage planetary gear train includes a secondary sun gear (not shown in the figure) arranged on the primary planet carrier, a secondary planetary gear 421 meshing with the secondary sun gear, a secondary inner gear ring 423 meshing with the secondary planetary gear 421, and a secondary planet carrier 424 driven to rotate by the secondary planetary gear 421. The third-stage planetary gear train includes a third-stage sun gear (not shown in the figure) disposed on the second-stage planetary carrier 424, a third-stage planetary gear (not shown in the figure) meshing with the third-stage sun gear, a third-stage inner gear ring (not shown in the figure) fixedly disposed relative to the housing and meshing with the third-stage planetary gear, and a third-stage planetary carrier 431 driven to rotate by the third-stage planetary gear. The third-stage planetary carrier 431 then transmits the rotational power to the output shaft 3.

[0032] Preferably, in this embodiment, the third-stage planet carrier 431 transmits power to the adapter 44 through a flat square structure (not shown in the figure), and the adapter 44 transmits power to the output shaft 3 through the flat square structure.

[0033] See also Figure 4 In order to change the rotation speed transmitted from the drive shaft 21 to the output shaft 3, the transmission mechanism changes its transmission ratio by moving the secondary inner gear ring 423 along the axial direction of the output shaft. Preferably, the secondary inner gear ring 423 can move along the axial direction of the output shaft 3 between a first switching position close to the motor 20 and a second switching position away from the motor 20. When located at the first switching position, the secondary inner gear ring 423 is fixed relative to the housing in the rotation direction, and the secondary inner gear ring 423 is meshed with the second planetary gear.

[0034] Preferably, in this embodiment, the primary inner gear ring 411 is fixedly arranged relative to the housing, and a first fixing member 4110 is provided at one end of the primary inner gear ring 411 close to the tool head, and a second fixing member 4230 is provided at one end of the secondary inner gear ring 423 close to the primary inner gear ring 411. When the secondary inner gear ring 423 is located at the first switching position, the first fixing member 4110 and the second fixing member 4230 are matched to fix the secondary inner gear ring 423 in the rotation direction relative to the housing 10. When the secondary inner gear ring 423 is located at the second switching position, the secondary inner gear ring 423 is meshed with the secondary planetary gear 421 and the secondary planetary carrier 424 at the same time, and rotates with the secondary planetary gear 421 and the secondary planetary carrier 424.

[0035] It should be noted that, in this embodiment, only one implementation method is provided in which the secondary internal gear ring 423 changes the transmission ratio of the transmission mechanism 40 by axial movement. It can be understood that other methods can also be used to fix the secondary internal gear ring 423 relative to the housing, which will not be repeated here.

[0036] See also Figure 2 , Figure 5 and Figure 7 The power tool further includes an operating member 50 movably disposed on the housing, and the operating member drives the secondary inner gear ring 423 to move between the first switching position and the second switching position through the elastic member, that is, the operating member 50 is axially located along the output shaft 3 in the first operating position (see Figure 5 The elastic member 50 is driven to move along the axial direction of the output shaft, and the elastic member drives the secondary gear ring 423 to move along the axial direction of the output shaft between the first switching position and the second switching position. Preferably, the elastic member is a deformable steel wire 60. The steel wire 60 is roughly arched, symmetrically arranged relative to the axis of the output shaft, and includes two free ends 61 that are matched with the secondary inner gear ring 423. Preferably, a radial hole (not shown in the figure) is provided on the secondary inner gear ring 423, and the two free ends are inserted into the radial hole. Under the action of the operating member 50, the steel wire 60 moves along the axial direction of the output shaft and drives the secondary inner gear ring 423 to move between the first switching position and the second switching position. It can be understood that the steel wire 60 can also perform pivotal motion under the action of the operating member 50, but at the same time it can drive the secondary inner gear ring 423 to move between the first switching position and the second switching position, which will not be repeated here.

[0037] In this embodiment, in order to realize the positioning of the secondary inner gear ring 423 at the first switching position and the second switching position, an abutment member 100 is provided on the housing. When the external force applied to the steel wire 60 by the operator through the operating member 50 is greater than the elastic force of the steel wire 60 itself, the steel wire 60 can be elastically deformed to overcome the stopping effect of the stop member 100 on it, thereby being able to drive the secondary inner gear ring to move from one of the first and second switching positions to the other of the two; when the external force applied to the steel wire 60 is less than the elastic force of the steel wire itself, the steel wire 60 abuts against the stop member 100 to prevent the secondary inner gear ring 423 from switching from one of the first switching position and the second switching position to the other of the two. In this embodiment, preferably, the main body is provided with a notch 1024, one of the main body 1020 and the operating member 50 is provided with a guide rail, and the other of the two is provided with a guide groove, so that the operating member 50 can be slidably disposed in the above-mentioned notch 1024.

[0038] Continue to see Figure 3 as well as Figure 8-Figure 10The operating member 50 includes an operating panel 501, and the operating panel 501 is at least partially exposed in the notch 1024. Guide rails 5011 are provided on both sides of the operating panel 501, and a guide groove 1023 is provided on the main body 1020. The main body 1020 also includes a base plate 1022 located between the operating panel 501 and the gear box housing 101. Preferably, the base plate 1022 is horizontally arranged, and the operating panel 501 is slidably supported on the base plate 1022. Therefore, the arrangement of the base plate 1022 not only makes the movement of the operating member 50 smoother, but also makes the structure of the main body 1020 more solid and reliable. It should be noted that the horizontal direction mentioned in this embodiment refers to the horizontal direction in which the operating member 501 is horizontally arranged. Figure 5 The orientation shown is taken as an example, which is a plane parallel to the X-axis and perpendicular to the Y-axis.

[0039] See also Figure 8 and Fig. 9 The operating member 50 also includes a clamping portion 5012 fixed to the operating plate 501 and used to clamp the elastic member. The clamping portion 5012 includes a first clamping plate 5013 and a second clamping plate 5014, and the first and second clamping plates 5013 and 5014 are respectively located on both sides of the steel wire along the output axis. By arranging the first clamping plate 5013 and the second clamping plate 5014 on both sides of the steel wire 60, the movement of the steel wire 60 along the output shaft axis under the action of the operating member 50 will be smoother. The clamping portion 5012 is provided with a stop groove 5015 extending in the axial direction, and the base plate 1022 extends into the stop groove 5015. Therefore, when the operating member 50 moves under the action of an external force, the matching between the base plate 1022 and the stop groove 5015 can also provide a guiding effect on the operating member 50. The stopper 100 is disposed on the base plate 1022 and extends to the stopper groove 5015 . The steel wire 60 is exposed in the stopper groove 5015 and can abut against the stopper 100 .

[0040] In this embodiment, in order to better enable the steel wire 60 to drive the secondary inner gear ring to move along the axial direction of the output shaft, the steel wire is roughly arched, including a clamping section 62 matched with the clamping portion 5012 and an arc section 63 located between the clamping section 62 and the free end. The arc section 63 is matched in shape and arranged around the outer periphery of the gear box housing 101. When the operating member 50 drives the steel wire 60 to move under the action of an external force, the arc section 63 moves along the outer peripheral surface of the gear box housing 101. In addition, the clamping section 62 includes a stopper section 621 extending in the longitudinal direction to abut against the stopper 100.

[0041] See also Figure 1 In this embodiment, the area of ​​the substrate 1022 is larger than the area of ​​the notch of the notch 1024. In addition, a ring 1025 matching the shape of the notch is provided at the notch of the notch 1024. The provision of the ring 1025 not only has an aesthetic effect, but also can prevent dust from entering the shell through the notch.

[0042] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0043] In the description of the present invention, "first feature" or "second feature" may include one or more of the features.

[0044] In the description of the present invention, "plurality" means two or more.

[0045] In the description of the present invention, a first feature being “on” or “under” a second feature may include that the first and second features are directly in contact with each other, or may include that the first and second features are not in direct contact with each other but are in contact with each other via another feature therebetween.

[0046] In the description of the present invention, “on”, “over” and “above” a first feature from a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0047] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0048] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A handheld power tool comprising: A motor for outputting rotational power; A housing for accommodating the motor; An operating member, movably disposed relative to the housing; Output shaft, used for connecting with tool head; A transmission mechanism, comprising a speed change ring gear, wherein the speed change ring gear is movable between a first switching position and a second switching position so that the transmission mechanism can transmit the rotation speed of the motor to the output shaft at different transmission ratios; as well as An elastic member is transmission-connected between the operating member and the speed gear ring; it is characterized in that: the hand-held power tool also includes a stop member arranged on the shell, the operating member includes an operating plate and a clamping part fixed on the operating plate, the elastic member includes a clamping section matched with the clamping section, and the clamping section includes a stop section elastically abutting against the stop member; the stop member abuts against the stop section to prevent the elastic member from driving the speed gear ring to switch freely between the first switching position and the second switching position; when the external force applied to the elastic member by the operator through the operating member is greater than the elastic force of the elastic member itself, the elastic member can be elastically deformed to overcome the stopping effect of the stop member on the stop section so as to drive the speed gear ring to move from one of the first and second switching positions to the other of the two; when the external force applied to the elastic member is less than the elastic force of the elastic member itself, the stop section abuts against the stop member to prevent the speed gear ring from switching from one of the first switching position and the second switching position to the other of the two.

2. The handheld power tool according to claim 1, characterized in that: The elastic member comprises a steel wire, the steel wire comprises a free end for matching with the speed change gear ring, and the two free ends of the steel wire are arranged on both sides of the output shaft axis.

3. The handheld power tool according to claim 1, characterized in that: The elastic member drives the speed change gear ring to move between a first switching position and a second switching position along the axial direction of the output shaft under the action of the operating member.

4. The handheld power tool according to claim 1, characterized in that: The housing comprises a gear box housing wrapped around the outer periphery of the transmission mechanism and a main body covering at least a portion of the motor and the gear box housing.

5. The handheld power tool according to claim 4, characterized in that: The main body is provided with a notch, and one of the main body and the operating member is provided with a guide rail, and the other of the two is provided with a guide groove, so that the operating member can be slidably arranged in the notch.

6. The handheld power tool according to claim 5, characterized in that: The operating plate is at least partially exposed in the notch, and the main body further comprises a base plate located between the operating plate and the gear box housing, and the operating plate is slidably supported on the base plate.

7. The handheld power tool according to claim 1, characterized in that: The clamping portion includes a first clamping plate and a second clamping plate, and the first clamping plate and the second clamping plate are respectively located on two sides of the elastic member along the output axis.

8. The handheld power tool according to claim 6, characterized in that: The clamping portion is provided with a stop groove extending along the axial direction, and the base plate extends into the stop groove.

9. The handheld power tool according to claim 6, characterized in that: The clamping portion is provided with a stop groove extending in the axial direction, the stop member is arranged on the base plate and extends to the stop groove, and the elastic member is exposed in the stop groove and can abut against the stop member.

10. The handheld power tool according to claim 1, characterized in that: The elastic member is integrally formed from a steel wire.

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