Gear reversing mechanism for electric tool switches

Abstract

The present invention relates to a gear reversing mechanism applied to a switch of an electric tool, comprising a housing, a housing having an accommodating chamber, a housing at one end of the accommodating chamber being rotatably connected to a rotating shaft, a dial handle and a swing arm being connected to the rotating shaft, the dial handle extending out of the housing for a dialing operation, the swing arm being inserted into the accommodating chamber to realize swinging, at least two positioning grooves being arranged on the side wall on either side of the swinging surface of the swing arm, the distances between each positioning groove and the central axis of the rotating shaft being equal, a positioning hole being provided on the housing opposite to any positioning groove, the outer end of the positioning hole being away from the positioning groove, the positioning hole being provided with a cover, an elastic member and a positioning and tightening member in sequence from the outer end to the inner end, the elastic force of the elastic member pressing one end of the positioning and tightening member into the positioning groove, and the end of the positioning and tightening member pressed into the positioning groove being spherical. The present invention can achieve the technical effects of a larger shifting angle and a clearer gear switching feeling.

Description

Technical field:

[0001] The invention belongs to the technical field of electric tool switches, and in particular relates to a gear position reversing mechanism applied to an electric tool switch. Background technology:

[0002] The control system of the power tool includes a start-stop switch, a speed control switch and a gear reversing mechanism. The start-stop switch is used to control the start and stop of the power tool, the speed control switch is used to adjust the speed of the power tool motor, and the gear reversing mechanism is used to change the direction of the power tool motor.

[0003] At present, the gear reversing mechanisms commonly used in power tool switches are all of the toggle type. By toggling the toggle handle, the swing arm is driven to swing, and the connection method between the spring on the swing arm and the metal foil on the PCB board is adjusted to change the direction of the motor. Since the toggle handle can be toggled, in order to avoid the toggle handle being accidentally toggled during the operation of the motor, the gear reversing mechanism also includes a swing arm positioning device. For example, the gear reversing mechanism disclosed in the invention patent "Reversing switch for power tools" (patent number: ZL201610779856.2), the swing arm and the swing arm positioning device are arranged radially along the rotating shaft, and a plurality of positioning grooves are provided at the end of the swing arm. Steel balls are elastically provided on the swing arm positioning device. The swing arm swings to make the steel balls fit into different positioning grooves to realize the shifting of the gear reversing mechanism. When the internal space of the switch is limited, this structure directly leads to a shortening of the length of the swing arm. The shortening of the swing arm length directly affects the reduction of the swing arc length of the swing arm away from the end of the rotating shaft. The smaller swing arc length makes the spacing between the positioning grooves set on the swing arm smaller, and it is easy to jump gears when the handle is turned to change direction. Therefore, there are technical problems of inconvenience and misoperation in operation. Summary of the invention:

[0004] The first technical problem to be solved by the present invention is to provide a gear reversing mechanism for an electric tool switch with a larger gear shift angle and a clearer gear switching feeling.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is: a gear switching mechanism applied to an electric tool switch, comprising a shell, a accommodating chamber is arranged inside the shell, a rotating shaft is rotatably connected to the shell at one end of the accommodating chamber, a dial handle and a swing arm are connected to the rotating shaft, the dial handle extends out of the shell for dialing operation, and the swing arm is inserted into the accommodating chamber to realize swinging, and at least two positioning grooves are arranged on the side wall on either side of the swinging surface of the swing arm, and the distances from each positioning groove to the central axis of the rotating shaft are equal, and a positioning hole is opened on the shell that is opposite to any positioning groove, and the outer end of the positioning hole is away from the positioning groove, and the positioning hole is sequentially provided with a cover, an elastic member and a positioning and tightening member from the outer end to the inner end, and the elastic force of the elastic member presses one end of the positioning and tightening member into the positioning groove, and the end of the positioning and tightening member pressed into the positioning groove forms a spherical surface.

[0006] As a preferred solution, there are three positioning grooves, each of which is a hemispherical pit, a bucket-shaped pit, or a rectangular pit. The cover is inserted into the positioning hole and is threaded, glued, or frictionally clamped to the inner wall of the positioning hole. The elastic part is a spring or rubber, and the positioning and tightening part can be a ball or a column with a spherical surface at least at one end.

[0007] As a preferred solution, the shell includes a base and an upper cover, the positioning hole is opened on the side wall of the base, a baffle is provided on the edge of the upper cover, the upper cover is connected to the base, and the baffle is in contact with the outer wall of the base and covers the positioning hole.

[0008] As a preferred solution, a contact spring is provided on the side wall of the swing arm on either side in the swinging direction thereof, for contacting or disconnecting with a contact terminal provided inside the housing to switch the direction of the motor.

[0009] As a preferred solution, the positioning groove is arranged at an end of the swing arm away from the rotating shaft.

[0010] The beneficial effects of the present invention are as follows: the present invention arranges the positioning groove on the side wall of the swing arm on either side of its swing surface, and then arranges the positioning and tightening member, the elastic member and the cover on the shell; the swing arm is positioned by the cooperation of the positioning and tightening member arranged on the shell and the positioning groove; the positioning and tightening member is transferred from one positioning groove to another positioning groove through the swing of the swing arm to realize the gear switching; this method can effectively extend the length of the swing arm, increase the swing arc length of the positioning groove, and increase the spacing between the positioning grooves, thereby realizing a gear switching mechanism with a larger gear shifting angle and a clearer gear switching feeling. Description of the drawings:

[0011] The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings, wherein:

[0012] Figure 1 is an exploded view of the gear reversing mechanism of the present invention;

[0013] Figure 2 It is a cross-sectional view of the gear reversing mechanism of the present invention in an assembled state.

[0014] Figure 1 and Figure 2 In: 1. shell, 101. base, 102. upper cover, 103. baffle, 2. accommodating cavity, 3. rotating shaft, 4. dial handle, 5. swing arm, 6. positioning groove, 7. positioning hole, 8. sealing cover, 9. elastic member, 10. positioning and tightening member, 11. contact spring. Specific implementation method:

[0015] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0016] like Figure 1 and Figure 2 As shown, a gear reversing mechanism applied to an electric tool switch comprises a shell 1, a housing 2 is provided inside the shell 1, a rotating shaft 3 is rotatably connected to the shell 1 at one end of the housing 2, a dial handle 4 and a swing arm 5 extending radially along the rotating shaft 3 are connected to the rotating shaft 3, the dial handle 4 extends out of the shell 1 for a dialing operation, the swing arm 5 is inserted into the housing 2 to achieve swinging, at least two positioning grooves 6 are provided on the side wall on either side of the swinging surface of the swing arm 5, and the distances between each positioning groove 6 and the central axis of the rotating shaft 3 are equal, a positioning hole 7 is provided on the shell 1 and is opposite to any positioning groove 6, the outer end of the positioning hole 7 is away from the positioning groove 6, and a cover 8, an elastic member 9 and a positioning and tightening member 10 are sequentially provided on the positioning hole 7 from the outer end to the inner end, the elastic force of the elastic member 9 presses one end of the positioning and tightening member 10 into the positioning groove 6, and the end of the positioning and tightening member pressed into the positioning groove 6 forms a spherical surface.

[0017] In the present embodiment, there are three positioning grooves 6, each positioning groove 6 is a hemispherical pit, a bucket-shaped pit or a rectangular pit, preferably a hemispherical pit, and the cover 8 is inserted into the positioning hole 7, and is threadedly connected or glued or frictionally clamped to the inner wall of the positioning hole 7. In the present embodiment, threaded connection is preferably used. The elastic member 9 is a spring or rubber, preferably a spring; the positioning and tightening member 10 can be a round ball or a column with a spherical surface at least at one end. In the present embodiment, a round ball is preferred, and a round steel ball is further preferred.

[0018] like Figure 1 As shown, the shell 1 includes a base 101 and an upper cover 102, the positioning hole 7 is opened on the side wall of the base 101, and a baffle 103 is arranged on the edge of the upper cover 102. The upper cover 102 is connected to the base 101, and the baffle 103 is in contact with the outer wall of the base 101 and covers the positioning hole 7 to prevent the cover 8 from falling off, thereby improving the aesthetics and the dustproof level.

[0019] The swing arm 5 is provided with a contact spring 11 on any side wall in the swing direction thereof, which is used to contact or disconnect with the contact terminal provided inside the housing 1 to switch the direction of the motor. In this embodiment, the contact spring 11 is provided on any side wall in the swing direction of the swing arm 5. When the swing arm swings, the contact spring 11 approaches or moves away from the contact terminal. When the contact spring 11 overlaps with the contact terminal, the motor is in a forward rotation state. When the contact spring 11 separates from the contact terminal, the motor is in a reverse rotation state.

[0020] The positioning groove 6 is arranged at one end of the swing arm 5 away from the rotating shaft 3, and the distance between the positioning grooves 6 is expanded as much as possible, so that the gear shifting angle is larger and the gear switching feeling is clearer.

[0021] The working process of the present invention is: Figure 1 and Figure 2 As shown, first Figure 2 Install the gear reversing mechanism as shown in the figure, insert the positioning and tightening member 10 into any positioning groove 6, and then press Figure 1 As shown, artificial Figure 1 When the dial handle 4 is toggled on the right side, the swing arm 5 swings to the left. When the swing arm 5 swings, it drives the positioning slot 6 to move relative to the positioning and tightening member 10, so that the positioning and tightening member 10 moves from one positioning slot 6 to another positioning slot 6 adjacent to its right, realizing a gear shift. When the positioning and tightening member 10 moves to the rightmost positioning slot 6, the swing arm 5 swings to the left with the maximum amplitude. At this time, the contact spring 11 contacts the contact terminal, causing the motor to rotate forward.

[0022] When it is necessary to switch the direction of the motor, the operator turns the handle 4 in the opposite direction to make the swing arm 5 swing to the right. As long as the swing arm 5 swings one gear to the right, the contact spring 11 is disconnected from the contact terminal, and the motor can be reversed. Further turning the handle 4 in the opposite direction can make the positioning and tightening member 10 inserted into the leftmost positioning groove 6. At this time, the contact spring 11 is farthest from the contact terminal, but the motor is still in the reverse state.

[0023] Although three positioning grooves 6 are provided in this embodiment, in actual use, only two positioning grooves 6 may be provided, and the technical effect to be achieved by the present invention can also be fully achieved.

[0024] The above embodiments are only illustrative of the principles and effects of the invention, as well as some embodiments of its application, and are not intended to limit the invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the invention, and all of these belong to the protection scope of the invention.

Claims

1. A gear reversing mechanism for a switch of an electric tool, comprising a housing (1), wherein a receiving chamber (2) is arranged inside the housing (1), a rotating shaft (3) is rotatably connected to the housing (1) at one end of the receiving chamber (2), a dial handle (4) and a swing arm (5) are connected to the rotating shaft (3), the dial handle (4) extends out of the housing (1) for a dialing operation, and the swing arm (5) is inserted into the receiving chamber (2) to achieve swinging, characterized in that: The swing arm (5) is provided with at least two positioning grooves (6) on the side wall on any side of the swing surface thereof, and the distances between each positioning groove (6) and the central axis of the rotating shaft (3) are equal. The housing (1) is provided with a positioning hole (7) directly opposite to any positioning groove (6), and the outer end of the positioning hole (7) is away from the positioning groove (6). The positioning hole (7) is provided with a cover (8), an elastic member (9) and a positioning and tightening member (10) in sequence from the outer end to the inner end. The elastic force of the elastic member (9) presses one end of the positioning and tightening member (10) into the positioning groove (6), and the end of the positioning and tightening member pressed into the positioning groove (6) forms a spherical surface.

2. The gear position reversing mechanism for an electric tool switch according to claim 1, characterized in that: The number of the positioning grooves (6) is three, and each positioning groove (6) is in the form of a hemispherical pit, a bucket-shaped pit, or a rectangular pit. The cover (8) is inserted into the positioning hole (7), and the cover (8) is threadedly connected, glued, or frictionally clamped to the inner wall of the positioning hole (7). The elastic member (9) is a spring or rubber, and the positioning and tightening member (10) is a round ball or a columnar member with at least one end being a spherical surface.

3. The gear position reversing mechanism for an electric tool switch according to claim 1, characterized in that: The housing (1) comprises a base (101) and an upper cover (102); the positioning hole (7) is formed on a side wall of the base (101); a baffle (103) is provided on the edge of the upper cover (102); the upper cover (102) is connected to the base (101) in a mating relationship; the baffle (103) is in contact with an outer wall of the base (101) and covers the positioning hole (7).

4. The gear position reversing mechanism for a power tool switch according to claim 1, characterized in that: A contact spring (11) is provided on a side wall of the swing arm (5) on either side in the swing direction thereof, and the contact spring (11) is used to contact or disconnect with a contact terminal provided inside the housing (1) to switch the direction of rotation of the motor.

5. The gear position reversing mechanism for a power tool switch according to claim 1, characterized in that: The positioning groove (6) is arranged at an end of the swing arm (5) away from the rotating shaft (3).

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