Brake assembly, power tool switch, and power tool

Abstract

The application discloses a brake assembly, an electric tool switch and an electric tool. The brake assembly is partially arranged in the electric tool switch and is used for short-circuiting a D terminal connected with a motor and a main circuit terminal in the electric tool switch. The brake assembly comprises a push rod, a brake pad and a brake spring. The brake pad is arranged on the push rod, and the brake spring is arranged between the brake pad and the push rod. The brake pad comprises a short-circuit part. The brake pad has an initial state and a braking state. When the brake pad is in the initial state, the short-circuit part is arranged to be inclined to a side close to the D terminal. When the brake pad is in the braking state, the short-circuit part is arranged to be parallel to the push rod, and the short-circuit part abuts against the D terminal and the main circuit terminal respectively. The brake assembly can improve the braking life of the electric tool switch and prolong the service life of the electric tool. Accordingly, the application further provides an electric tool switch and an electric tool.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electric tools, in particular to a brake assembly, an electric tool switch and an electric tool. BACKGROUND

[0002] In order to ensure the safety of electric tools, the electric tools are required to stop immediately when the electric tool switch is turned off, so as to prevent the electric tools from continuing to work under the action of inertia after the electric tool switch is turned off, and thus to prevent the electric tools from causing harm to human bodies. Therefore, the electric tools such as electric drills, electric wrenches, electric saws and electric hammers are required to have a brake function of the electric tool switch, so that the electric tools can be stopped immediately by the brake of the electric tool switch when the whole machine needs to be stopped.

[0003] The existing brake of the electric tool is that when the electric tool switch is returned from the working position to the brake position, the brake pad shorts the D terminal and the main circuit terminal (the main circuit terminal and the D terminal are connected to two terminals of the motor), so as to release the back electromotive force generated by the motor due to the rotational inertia, and to achieve the purpose of rapidly stopping the motor. However, the motor working due to the inertia will generate electric arc or electric spark when the brake pad shorts the D terminal and the main circuit terminal, and thus to ablate the contact positions of the three parts. In the traditional brake mechanism design, the brake pad simultaneously contacts the hardware parts connected to the two terminals of the motor. However, due to the machining deviation and assembly deviation, the brake pad will randomly contact one of the terminals first, and thus to ablate the terminal contacted later. At the same time, due to the need of the structure design of the switch, the two terminals have different ablation resistance, and the effective area of the D terminal is smaller and the ablation resistance is poor. If the brake pad contacts the D terminal later, the service life of the brake of the switch will be greatly reduced, and thus to affect the service life of the electric tool. SUMMARY

[0004] An object of the present application is to provide a brake assembly, which can improve the service life of the brake of the electric tool switch, and prolong the service life of the electric tool.

[0005] Another object of the present application is to provide an electric tool switch, which can overcome the technical problem of low service life of the brake of the traditional electric tool switch.

[0006] Still another object of the present application is to provide an electric tool with long service life.

[0007] To achieve the above objects, in one aspect, the present application adopts the following technical solutions:

[0008] A brake assembly partially arranged in a power tool switch for short-circuiting a D terminal connected to a motor and a main circuit terminal in the power tool switch, comprising a push rod, a brake pad and a brake spring, the brake pad being mounted on the push rod, and the brake spring being arranged between the brake pad and the push rod, wherein the brake pad comprises a short-circuiting portion, the brake pad has an initial state and a braking state, when the brake pad is in the initial state, the short-circuiting portion is arranged to be inclined to a side close to the D terminal, and when the brake pad is in the braking state, the short-circuiting portion is arranged to be parallel to the push rod, and the short-circuiting portion abuts against the D terminal and the main circuit terminal respectively.

[0009] In one of the embodiments, the brake pad further comprises a connecting portion, the push rod is provided with a first mounting portion, the connecting portion is sleeved on the first mounting portion, the short-circuiting portion is connected with the connecting portion, and the brake spring is arranged between the short-circuiting portion and the first mounting portion.

[0010] In one of the embodiments, the connecting portion comprises a first connecting segment, a second connecting segment and a third connecting segment connected in sequence, the short-circuiting portion comprises a fourth connecting segment, a short-circuiting segment and a fifth connecting segment connected in sequence, the first connecting segment is connected with the fourth connecting segment and arranged to be parallel to the fourth connecting segment, the third connecting segment is connected with the fifth connecting segment, and the third connecting segment and the fifth connecting segment are both arranged to be inclined, and an inclined included angle with a preset angle is formed between an extension line of the third connecting segment and an extension line of the fifth connecting segment.

[0011] In one of the embodiments, an inclined guide surface is arranged on an end of the first mounting portion away from the brake spring, and the inclined guide surface abuts against the connecting portion.

[0012] In one of the embodiments, the brake assembly further comprises a spring sheet, the spring sheet is arranged between the first mounting portion and the brake pad, one end of the spring sheet is connected with the first mounting portion, the other end of the spring sheet abuts against the short-circuiting portion, and the spring sheet generates a pushing force on the short-circuiting portion to incline the short-circuiting portion to the side close to the D terminal.

[0013] In one of the embodiments, a baffle for preventing the brake pad from falling off is arranged on the first mounting portion.

[0014] In one of the embodiments, a first protrusion is arranged on the first mounting portion, the brake spring is sleeved with the first protrusion, a second protrusion is arranged on the short-circuiting portion, and the brake spring is sleeved with the second protrusion.

[0015] In one of the embodiments, the brake shoe further comprises a connecting portion, the push rod is provided with a first mounting portion and a second mounting portion, the first mounting portion is provided with a guide inclined surface, the connecting portion is sleeved on the first mounting portion, and the connecting portion is in abutment with the guide inclined surface, the short connecting portion is connected with the connecting portion, one end of the brake spring is fixedly connected with the second mounting portion, and the other end of the brake spring is fixedly connected with the connecting portion.

[0016] In another aspect, the application further provides an electric tool switch comprising the brake assembly.

[0017] In another aspect, the application further provides an electric tool switch comprising the brake assembly.

[0018] In the brake assembly, the brake shoe is mounted on the push rod, the short connecting portion of the brake shoe is obliquely arranged towards the side close to the D terminal when the brake shoe is in the initial state, and when the electric tool switch is disconnected from the working state, the brake shoe moves from the working position to the brake position together with the push rod. Since the short connecting portion of the brake shoe is obliquely arranged towards the side close to the D terminal, when the brake shoe moves to the brake position, the short connecting portion first contacts the D terminal. After the brake shoe contacts the D terminal, the brake shoe continues to retreat together with the push rod, the D terminal generates a pushing force on the brake shoe, and the brake shoe is gradually adjusted, the short connecting portion is gradually adjusted from the oblique position to be parallel to the push rod, the brake shoe is adjusted, the short connecting portion contacts the main circuit terminal, the brake shoe is in the brake state, and the brake function is generated. In the brake assembly, the brake shoe first contacts the D terminal with poor ablation resistance during the braking process, and then contacts the main circuit terminal with strong ablation resistance, so that the brake life of the electric tool switch can be greatly improved, and the service life of the electric tool can be prolonged.

[0019] The electric tool switch of the application can effectively improve the brake life by applying the brake assembly. Further, the electric tool of the application has the beneficial effect of long service life by applying the electric tool switch. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a structural schematic view of the brake assembly in one embodiment;

[0021] Figure 2 is Figure 1 is a structural schematic view of the brake shoe in the brake assembly shown in the figure;

[0022] Figure 3 is a structural schematic view of the brake shoe and the D terminal in the brake assembly in one embodiment;

[0023] Figure 4 is a structural schematic view of the brake assembly in one embodiment in the brake state;

[0024] Figure 5 is a structural schematic diagram of a brake assembly in another embodiment;

[0025] Figure 6 is a structural schematic diagram of a brake assembly in another embodiment;

[0026] Figure 7 is a structural schematic diagram of a brake assembly in another embodiment.

[0027] Explanation of reference signs:

[0028] 10-D terminal, 20-main circuit terminal, 40-spring piece;

[0029] 31-push rod, 32-brake pad, 33-brake spring;

[0030] 311-first mounting portion, 312-second mounting portion, 321-connection portion, 322-short connection portion;

[0031] 3111-guide inclined surface, 3112-baffle, 3211-first connection segment, 3212-second connection segment, 3213-third connection segment, 3221-fourth connection segment, 3222-short connection segment, 3223-fifth connection segment, 3224-second protrusion. DETAILED DESCRIPTION

[0032] The technical solutions of the present application will be further described below in combination with the drawings and through specific embodiments.

[0033] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0034] Please also refer to Figures 1 to 4The embodiment provides a brake assembly which is partially arranged in a power tool switch and used for short-circuiting a D terminal 10 connected with a motor and a main circuit terminal 20 in the power tool switch, the brake assembly comprises a push rod 31, a brake pad 32 and a brake spring 33, the brake pad 32 is arranged on the push rod 31, and the brake spring 33 is arranged between the brake pad 32 and the push rod 31, wherein the brake pad 32 comprises a short-circuit part 322, the brake pad 32 has an initial state and a braking state, when the brake pad 32 is in the initial state, the short-circuit part 322 is arranged to be inclined to a side close to the D terminal 10, and when the brake pad 32 is in the braking state, the short-circuit part 322 is arranged to be parallel to the push rod 31, and the short-circuit part 322 abuts against the D terminal 10 and the main circuit terminal 20 respectively.

[0035] In the brake assembly, the brake pad 32 is arranged on the push rod 31, when the brake pad 32 is in the initial state, the short-circuit part 322 of the brake pad 32 is arranged to be inclined to the side close to the D terminal 10, when the power tool switch is disconnected from the working state, the brake pad 32 moves from the working position to the braking position together with the push rod 31, because the short-circuit part 322 of the brake pad 32 is arranged to be inclined to the side close to the D terminal 10, when the brake pad 32 moves to the braking position, the short-circuit part 322 first contacts the D terminal 10, after the brake pad 32 contacts the D terminal 10, the brake pad 32 continues to retreat together with the push rod 31, the D terminal 10 generates a pushing force on the brake pad 32 and gradually adjusts the brake pad 32, the short-circuit part 322 gradually adjusts from the inclined position to be parallel to the push rod 31, after the brake pad 32 is adjusted, the short-circuit part 322 contacts the main circuit terminal 20, the brake pad 32 is in the braking state, and the brake function is generated. In the brake assembly, the brake pad 32 first contacts the D terminal 10 with poor ablation resistance and then contacts the main circuit terminal 20 with strong ablation resistance during the braking process, so that the braking life of the power tool switch can be greatly improved, and the service life of the power tool can be prolonged.

[0036] In one embodiment, the brake pad further comprises a connecting part 321, the push rod 31 is provided with a first mounting part 311, the connecting part 321 is sleeved on the first mounting part 311, the short-circuit part 322 is connected with the connecting part 321, and the brake spring 33 is arranged between the short-circuit part 322 and the first mounting part 311. Specifically, the first mounting part 311 can be but is not limited to a mounting boss protruding from the surface of the push rod 31.

[0037] In this embodiment, the brake pad 32 is sleeved on the first mounting portion 311 via the connecting portion 321. When the brake pad 32 is in the initial state, the shorting portion 322 of the brake pad 32 is inclined towards the side closer to the D terminal 10. When the power tool switch is disconnected from the working state, the brake pad 32 moves from the working position to the braking position along with the push rod 31. Since the shorting portion 322 of the brake pad 32 is inclined towards the side closer to the D terminal 10, when the brake pad 32 moves to the braking position, the shorting portion 322 first contacts the D terminal 10 (e.g., ...). Figure 3 As shown), after the brake pad 32 contacts the D terminal 10, the brake pad 32 continues to retract with the push rod 31. The D terminal 10 generates a pushing force on the brake pad 32. Under the action of this pushing force, the connecting part 321 rotates around the first mounting part 311, thereby gradually aligning the brake pad 32. The shorting part 322 gradually aligns from the inclined position to be parallel to the push rod 31. After the brake pad 32 is aligned, the shorting part 322 contacts the main circuit terminal 20 (as shown). Figure 4 As shown, brake pad 32 is in a braking state, generating a braking function. Further, when the power tool switch is switched from the off state to the working state, brake pad 32 moves away from D terminal 10 and main circuit terminal 20 with push rod 31, brake pad 32 returns to its initial state, and shorting part 322 tilts towards the side closer to D terminal 10.

[0038] In one embodiment, the connecting portion 321 includes a first connecting segment 3211, a second connecting segment 3212, and a third connecting segment 3213 connected in sequence; the shorting portion 322 includes a fourth connecting segment 3221, a shorting segment 3222, and a fifth connecting segment 3223 connected in sequence. The first connecting segment 3211 is connected to the fourth connecting segment 3221, and the first connecting segment 3211 and the fourth connecting segment 3221 are arranged parallel to each other; the third connecting segment 3213 is connected to the fifth connecting segment 3223, and both the third connecting segment 3213 and the fifth connecting segment 3223 are inclined, with the extension lines of the third connecting segment 3213 and the fifth connecting segment 3223 forming an inclined angle with a preset angle.

[0039] Specifically, the first connecting segment 3211 and the third connecting segment 3213 have the same length, the fourth connecting segment 3221 and the fifth connecting segment 3223 have the same length, the first connecting segment 3211 and the fourth connecting segment 3221 are arranged close to the main circuit terminal 20, and the third connecting segment 3213 and the fifth connecting segment 3223 are arranged close to the D terminal 10. The distance between the third connecting segment 3213 and the first connecting segment 3211 gradually increases from the end of the third connecting segment 3213 connected with the second connecting segment 3212 to the end of the third connecting segment 3213 connected with the fifth connecting segment 3223, and the distance between the fifth connecting segment 3223 and the fourth connecting segment 3221 gradually increases from the end of the fifth connecting segment 3223 connected with the short connecting segment 3222 to the end of the fifth connecting segment 3223 connected with the third connecting segment 3213, that is, the third connecting segment 3213 and the fifth connecting segment 3223 are both gradually inclined to the D terminal from the starting points thereof to the connecting positions thereof. Since the first connecting segment 3211 and the third connecting segment 3213 have the same length, the fourth connecting segment 3221 and the fifth connecting segment 3223 have the same length, and the third connecting segment 3213 and the fifth connecting segment 3223 are inclined to be arranged, the effective length of the third connecting segment 3213 and the fifth connecting segment 3223 is smaller than the sum of the lengths of the first connecting segment 3211 and the fourth connecting segment 3221, which causes the brake spring 33 to shrink on the side close to the fifth connecting segment 3223, and further causes the short connecting segment 322 to be inclined to the D terminal 10 side by the brake spring 33, so that the brake pad 32 is arranged to be inclined as a whole.

[0040] In one embodiment, the preset angle is 1°-10°, preferably 3°-4°.

[0041] Please refer to Figure 5In another embodiment, a guide slope 3111 is arranged on the first mounting portion 311 away from the one end of the brake spring 33, and the guide slope 3111 abuts against the connecting portion 321. Specifically, the length of the side edge of the first mounting portion 311 close to the D terminal 10 is greater than the length of the side edge of the first mounting portion 311 close to the main circuit terminal 20, so that the guide slope 3111 is formed at the end where the first mounting portion 311 abuts against the connecting portion 321. When the brake pad 32 is in the initial state, the connecting portion 321 abuts against the guide slope 3111 reliably, and then the short-circuiting portion 322 can be inclined to the side close to the D terminal 10. When the electric tool switch is disconnected from the working state, the brake pad 32 moves with the push rod 31 from the working position to the brake position, and the short-circuiting portion 322 moving with the brake pad 32 first contacts the D terminal 10. When the short-circuiting portion 322 contacts the D terminal 10, the brake pad 32 continues to retreat with the push rod 31, the D terminal 10 generates a pushing force on the brake pad 32, the connecting portion 321 rotates around the first mounting portion 311 under the action of the pushing force, the short-circuiting portion 322 gradually straightens until it contacts the main circuit terminal 20, the brake pad 32 is in the brake state, and the brake function is generated.

[0042] Please refer to Figure 6 In another embodiment, the brake assembly further comprises a spring sheet 40 arranged between the first mounting portion 311 and the brake pad 32, one end of the spring sheet 40 is arranged between the first mounting portion 311 and the connecting portion 321 and connected with the first mounting portion 311, the other end of the spring sheet 40 abuts against the short-circuiting portion 322, and the spring sheet 40 generates a pushing force on the short-circuiting portion 322 to incline the short-circuiting portion 322 to the side close to the D terminal 10. Specifically, when the brake pad 32 is in the initial state, the spring sheet 40 is stretched to generate a pushing force on the short-circuiting portion 322 to incline the short-circuiting portion 322 to the side close to the D terminal 10. When the electric tool switch is disconnected from the working state, the brake pad 32 moves with the push rod 31 from the working position to the brake position, and the short-circuiting portion 322 moving with the brake pad 32 first contacts the D terminal 10. When the short-circuiting portion 322 contacts the D terminal 10, the D terminal 10 generates a pushing force on the brake pad 32 to compress the spring sheet 40, the short-circuiting portion 322 gradually straightens until it contacts the main circuit terminal 20 with the push rod 20, the brake pad 32 is in the brake state, and the brake function is generated.

[0043] In one embodiment, the first mounting portion 311 is provided with a baffle 3112 for preventing the brake pad 32 from falling off. The baffle 3112 can abut against the connecting portion 321 when the brake pad 32 is popped up, so that the brake pad 32 can be blocked outside the connecting portion 321 to avoid falling off from the first mounting portion 311.

[0044] In one embodiment, the first mounting portion 311 is provided with a first protrusion (the first protrusion is blocked by the brake spring 33, not shown in the figure), and the brake spring 33 is sleeved with the first protrusion; the short-circuit portion 322 is provided with a second protrusion 3224, and the brake spring 33 is sleeved with the second protrusion 3224. Specifically, the first protrusion provided on the first mounting portion 311 is sleeved with the brake spring 33, and the second protrusion 3224 provided on the short-circuit portion 322 is sleeved with the brake spring 33, which can improve the installation stability of the brake spring 33 and avoid movement deviation or slipping and falling of the brake spring 33.

[0045] As shown in Figure 7 In another embodiment, the brake pad 32 further includes a connecting portion 321, the push rod 31 is provided with a first mounting portion 311 and a second mounting portion 312, the first mounting portion 311 is provided with a guide slope 3111, the connecting portion 321 is sleeved on the first mounting portion 311, and the connecting portion 321 abuts against the guide slope 3111, the short-circuit portion 322 is connected with the connecting portion 321, one end of the brake spring 33 is fixedly connected with the second mounting portion 312, and the other end of the brake spring 33 is fixedly connected with the connecting portion 321. Specifically, the first mounting portion 311 can be but is not limited to a mounting boss protruding from the surface of the push rod 31, and the length of the side edge of the first mounting portion 311 close to the D terminal 10 is greater than the length of the side edge of the first mounting portion 311 close to the main circuit terminal 20, so as to form the guide slope 3111 at the abutting end of the first mounting portion 311 and the connecting portion 321. When the brake pad 32 is in the initial state, the connecting portion 321 abutting against the guide slope 3111 reliably can realize the short-circuit portion 322 tilting towards the side close to the D terminal 10; when the electric tool switch is disconnected from the working state, the brake pad 32 moves from the working position to the brake position together with the push rod 31, the short-circuit portion 322 moving with the brake pad 32 first contacts the D terminal 10, when the short-circuit portion 322 contacts the D terminal 10, the brake pad 32 continues to retreat together with the push rod 31, the D terminal 10 generates a pushing force on the brake pad 32, the connecting portion 321 rotates around the first mounting portion 311 under the action of the pushing force, the short-circuit portion 322 gradually adjusts until contacting the main circuit terminal 20, the brake pad 32 is in the brake state, and the brake function is generated. In this embodiment, the brake spring 33 is arranged outside the brake pad 32, and the brake spring 33 is fixedly connected with the second mounting portion 312 and the brake pad 32 respectively, which helps to improve the installation stability of the brake spring 33.

[0046] On the other hand, the present application also provides an electric tool switch comprising the brake assembly of any one of the above, the electric tool switch of the present embodiment can effectively improve the brake life by applying the brake assembly. In another aspect, the present application also provides an electric tool comprising the electric tool switch of the above, the electric tool of the present embodiment has the beneficial effect of long service life by applying the electric tool switch.

[0047] Each technical feature of the above-described embodiments can be combined with any other technical feature, and for the sake of brevity, not all possible combinations are described, but it is understood that the scope of the present disclosure encompasses all such possible combinations.

[0048] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the scope of the patent of the present application should be subject to the appended claims.

Claims

1. A braking assembly, partially disposed within a power tool switch, for short-circuiting the D terminal (10) connecting the motor and the main circuit terminal (20) of the power tool switch, characterized in that, include: The device comprises a push rod (31), a brake pad (32), and a brake spring (33). The brake pad (32) is mounted on the push rod (31), and the brake spring (33) is disposed between the brake pad (32) and the push rod (31). The brake pad (32) includes a shorting portion (322). The brake pad (32) has an initial state and a braking state. When the brake pad (32) is in the initial state, the shorting portion (322) is inclined toward the side closer to the D terminal (10). When the brake pad (32) is in the braking state, the shorting portion (322) is parallel to the push rod (31), and the shorting portion (322) abuts against the D terminal (10) and the main circuit terminal (20) respectively. The brake pad also includes a connecting part (321), a first mounting part (311) is provided on the push rod (31), the connecting part (321) is sleeved on the first mounting part (311), the shorting part (322) is connected to the connecting part (321), and the brake spring (33) is disposed between the shorting part (322) and the first mounting part (311); The connecting part (321) includes a first connecting segment (3211), a second connecting segment (3212), and a third connecting segment (3213) connected in sequence; the shorting part (322) includes a fourth connecting segment (3221), a shorting segment (3222), and a fifth connecting segment (3223) connected in sequence; wherein, the first connecting segment (3211) is connected to the fourth connecting segment (3221), and the first connecting segment (3211) and the fourth connecting segment (3221) are arranged parallel to each other; the third connecting segment (3213) is connected to the fifth connecting segment (3223), and both the third connecting segment (3213) and the fifth connecting segment (3223) are inclined, and the extension line of the third connecting segment (3213) and the extension line of the fifth connecting segment (3223) form an inclined angle with a preset angle; The brake assembly also includes a spring plate (40), which is disposed between the first mounting portion (311) and the brake pad (32). One end of the spring plate (40) is connected to the first mounting portion (311), and the other end of the spring plate (40) abuts against the shorting portion (322). The spring plate (40) exerts a thrust on the shorting portion (322) to tilt the shorting portion (322) toward the side closer to the D terminal (10).

2. The braking assembly according to claim 1, characterized in that, A guide slope (3111) is provided at one end of the first mounting part (311) away from the brake spring (33), and the guide slope (3111) abuts against the connecting part (321).

3. The braking assembly according to claim 2, characterized in that, The first mounting part (311) is provided with a baffle (3112) for preventing the brake pad (32) from falling off.

4. The braking assembly according to claim 2, characterized in that, The first mounting part (311) is provided with a first protrusion, and the brake spring (33) is sleeved with the first protrusion; the shorting part (322) is provided with a second protrusion (3224), and the brake spring (33) is sleeved with the second protrusion (3224).

5. The brake assembly according to claim 1, characterized in that, The brake pad (32) further includes a connecting part (321). The push rod (31) is provided with a first mounting part (311) and a second mounting part (312). The first mounting part (311) is provided with a guide slope (3111). The connecting part (321) is sleeved on the first mounting part (311) and the connecting part (321) abuts against the guide slope (3111). The shorting part (322) is connected to the connecting part (321). One end of the brake spring (33) is fixedly connected to the second mounting part (312), and the other end of the brake spring (33) is fixedly connected to the connecting part (321).

6. A power tool switch, characterized in that, Includes the braking assembly as described in any one of claims 1 to 5.

7. A power tool, characterized in that, Includes the power tool switch as described in claim 6.

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