Cordless Power Tools

Abstract

The present invention discloses a rechargeable electric tool, comprising a casing, a motor fixed on the casing and a battery pack inserted into the casing, wherein the battery pack comprises an upper shell inserted into a handle, a base and a battery cell accommodated in the upper shell and the base, the upper shell comprises an inner cavity for mounting a circuit board, a terminal insertion port adjacent to one end of the circuit board and a plurality of narrow slots arranged at the other end, the base directly mounts and positions the battery cell without the need to additionally arrange an outer frame covering the outer periphery of the battery cell, thereby greatly reducing the diameter of the battery pack and providing a miniaturized, thin-handled handheld tool, furthermore, the upper shell and the base are provided with two sections to cover the battery cell, and narrow slots are arranged around the upper shell, thereby forming an air passage interconnected by the terminal insertion port, the inner cavity, the narrow slots and the opening, and discharging the heat in the battery pack out of the body through the air passage, thereby preventing the problem of excessive temperature of the battery pack.

Description

Technical Field

[0001] The invention relates to an electric tool, in particular to a rechargeable electric tool on a lithium battery tool. Background Art

[0002] Rechargeable handheld power tools are widely favored by users, such as lithium-powered wrenches, lithium-powered drills, lithium-powered angle grinders, etc. However, the battery packs used in low-voltage power tools are all inserted into the power tools. Therefore, a thin handle structure is required to meet the needs of users, especially female users. The thin handle is a selling point, but the existing battery packs are generally bundled and then installed in the battery pack shell. One is to provide assembly convenience, and the other is to prevent the battery pack from being loose and causing defects such as poor contact.

[0003] It is also understandable that in order to reduce the volume and weight of rechargeable power tools and ensure the compactness of the tools, lithium battery packs are usually designed as plug-in structures. Please refer to the U.S. invention patent application publication No. US20090208827A1, which discloses a handheld electric drill, that is, the user inserts the fully charged battery pack into the handle of the power tool to achieve work, operation and portability. Since the battery cell components are placed in a plastic shell to form a battery pack, and most of the battery pack is inserted into the tool, the battery pack will have a large current discharge during operation, causing the battery cell components to heat up. When the temperature of the battery cell surface rises to about 70 degrees, the controller in the machine or battery pack will shut off the power supply of the battery pack. The purpose is to protect the life of the battery. This frequent over-temperature protection will seriously affect the operator's work efficiency.

[0004] In view of this, it is indeed necessary to provide an improved rechargeable electric tool to overcome the defects of the prior art. Summary of the invention

[0005] In view of the deficiencies in the prior art, an object of the present invention is to provide a rechargeable electric tool with a thin handle and good heat dissipation performance.

[0006] The technical solution adopted by the present invention to solve the problems of the prior art is: a rechargeable electric tool, comprising a casing, a motor fixed on the casing and a battery pack inserted into the casing, the battery pack providing power to the motor, the casing having an outer shell and a handle connected to the outer shell, the motor being installed in the outer shell, and the battery pack being inserted into the handle; the battery pack having an upper shell inserted into the handle, a base and a battery cell accommodated in the upper shell and the base, the upper shell having an inner cavity for installing a circuit board, a terminal insertion port provided at one end adjacent to the circuit board and a plurality of narrow slots provided at the other end, the terminal insertion port and the narrow slots being communicated with the inner cavity respectively; the inner cavity depth of the upper shell is less than the length of the battery cell, when the battery cell is installed in the inner cavity and the protruding portion is accommodated in the base, the base having a positioning groove for installing the battery cell, a holding arm held on the handle and an opening located on at least one side of the holding arm, the opening connecting the inner cavity for installing the battery cell with the outside, the terminal insertion port, the inner cavity, the narrow slot and the opening forming an air passage connected to each other.

[0007] A further improvement scheme includes: the base has a lower bottom wall and a peripheral side wall surrounding the lower bottom wall, the above-mentioned holding arm is located on the peripheral side wall, the lower bottom wall has a plurality of raised arc-shaped ribs, the arc-shaped ribs are sleeved on the outer side surface of the battery cell, and the arc-shaped ribs are provided with air ports, and the airflow between the battery cells is connected to the air channel through the air ports.

[0008] A further improvement is as follows: the lower bottom wall has an inwardly recessed groove, the end of the groove is adjacent to the air port and is in communication with the air port.

[0009] Further improvement schemes include: the battery pack has a bracket located in the base, the bracket has a pad and a supporting part protruding from the pad, the pad has a groove facing the lower bottom wall, the supporting part has a supporting arc surface, the supporting arc surface abuts against the outer peripheral surface of the battery cell, and the groove is connected to the air channel.

[0010] A further improvement scheme includes: the supporting arc surfaces are arranged in four forms and respectively cooperate with the outer surface of the battery core.

[0011] A further improvement scheme includes: the bracket has a through hole penetrating the pad and the support portion, and the through hole is connected to the inner cavity and the groove.

[0012] A further improvement scheme includes: the battery pack has a sponge pad located between the battery core and the lower bottom wall, and the sponge pad has a notch connected to the groove.

[0013] A further improvement is as follows: the arc-shaped ribs are divided into four and are evenly distributed on the lower bottom wall.

[0014] A further improvement scheme includes: the upper shell has a buckling portion, the base has a snap portion, and the snap portion is snapped into a buckling groove of the buckling portion.

[0015] A further improvement is as follows: the distance from the surface of the battery cell to the inner side of the base is 2-2.5 mm.

[0016] Compared with the prior art, the present invention has the following beneficial effects: the present invention directly installs and positions the battery cell on the base, and there is no need to additionally set an outer frame covering the outer periphery of the battery cell, thereby greatly reducing the diameter of the battery pack to provide a miniaturized, thin-handled handheld tool. Furthermore, the upper shell and the base are provided with two sections to cover the battery cell, and a narrow groove is provided around the upper shell, thereby forming an air passage that is interconnected through the terminal insertion port, the inner cavity, the narrow groove and the opening, and the heat in the battery pack is discharged from the body through the air passage, thereby preventing the problem of excessive temperature of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings:

[0018] Figure 1 is a three-dimensional schematic diagram of the rechargeable electric tool of the present invention with the housing removed;

[0019] Figure 2 yes Figure 1 A three-dimensional schematic diagram of a battery pack of a rechargeable power tool;

[0020] Figure 3 yes Figure 2 Schematic diagram of the decomposition;

[0021] Figure 4 yes Figure 2 A three-dimensional schematic diagram of the middle and upper shell;

[0022] Figure 5 yes Figure 2 A three-dimensional schematic diagram without the base;

[0023] Figure 6 yes Figure 2 A three-dimensional schematic diagram of the middle base;

[0024] Figure 7 yes Figure 6 A cross-sectional view along the AA direction is shown;

[0025] Figure 8 yes Figure 2 A cross-sectional view along direction BB is shown;

[0026] Fig. 9 yes Figure 2 The cross-sectional view along the CC direction is shown, and a schematic diagram of the air flow in the air channel is presented. DETAILED DESCRIPTION

[0027] Specific examples of the implementation methods of the present invention will be described in detail below, wherein the words for directions such as front, back, left, right, up, and down involved in the present application are described based on the schematic diagrams of the embodiments placed in the figures to facilitate understanding, but do not represent structural changes of the product in other usage environments, and the embodiments described in the following exemplary implementation methods do not represent all embodiments consistent with this patent application.

[0028] See also Figure 1 As shown, a rechargeable electric tool disclosed by the present invention is shown. For ease of understanding, in the following description of the embodiment of the accompanying drawings, the electric drill implementation is mainly shown. Of course, the present invention can also be used in other handheld products. The rechargeable electric tool includes a housing 10, a motor 20 fixed on the housing, a battery pack 30 inserted into the housing, a gear box 40 and an output chuck 50. The battery pack 30 provides power to the motor 20 so that the rechargeable electric tool operates; the motor 20 drives the gear box 40 to rotate and drives the output chuck 50 to output. In order to increase the heat dissipation in the housing 10, a heat dissipation hole 100 is usually provided on the housing 10 to dissipate the heat in the housing 10 to prevent the over-high temperature from affecting the service life of the rechargeable electric tool.

[0029] The housing 10 comprises a shell 101 and a handle 102 connected to the shell 101. The motor 20 and the gear box 40 are respectively installed in the shell 101. The output clamp 50 is located at the front end of the shell 101. The battery pack 30 is inserted into the handle 102. In the embodiment of the present invention, the battery pack 30 comprises four battery cells 33, which can provide a maximum voltage output of 16V.

[0030] See also Figures 2 to 9 As shown, the battery pack 30 has an upper shell 31 inserted into the handle 102, a base 32 and a battery cell 33 accommodated in the upper shell 31 and the base 32, the upper shell 31 has a buckling portion 313, the base 32 has a snap portion 329, and the snap portion 329 is engaged in the buckling groove 314 of the buckling portion 313, and the two are assembled together to prevent the above-mentioned battery cell 33 from being exposed. In this embodiment, the buckling portion 313 and the buckling portion 329 are distributed around to provide a stable buckling effect, which is also in line with the state that the four battery cells are arranged in pairs.

[0031] In this embodiment, the upper shell 31 has an inner cavity 310 for installing the circuit board 80, a terminal insertion port 311 adjacent to one end of the circuit board 80, and a plurality of narrow slots 312 arranged at the other end. The insertion port 311 and the narrow slot 312 are respectively communicated with the inner cavity 310, and the depth of the inner cavity 310 of the upper shell 31 is less than the length of the battery cell. Therefore, part of the battery cell 33 protrudes out, and the protruding portion is temporarily defined as the protruding portion 330. When the battery cell 33 is installed in the inner cavity 310, the protruding portion 330 is accommodated in the base 32. Therefore, the protruding portion 330 is accommodated in the base 32. The present invention adopts a two-stage accommodation of the battery cell 33, which is beneficial to the heat dissipation of the battery cell, and can also prevent media such as water from flowing into the inner cavity 310 to cause a short circuit of the battery cell 33.

[0032] The base 32 has a lower bottom wall 320 and a peripheral side wall 321 surrounding the lower bottom wall. The lower bottom wall 320 of the base 32 has a positioning groove 322 for installing a battery cell, a holding arm 328 held on the handle 102, and an opening 324 located on at least one side of the holding arm 328. The holding arm 328 is located on the peripheral side wall 321. In the present embodiment, the opening 324 is located on both sides of the holding arm 328 to increase the elasticity of the holding arm 328. Of course, more importantly, the opening 324 connects the inner cavity 310 where the battery cell 33 is installed with the outside, so the terminal insertion port 311, the narrow slot 312 and the opening 324 form an air passage I that is connected to each other and connected to the outside (see Figure 5 , 9 The air passage is used to discharge the heat in the battery pack 30 out of the housing 10 , and at the same time, the heat in the battery cell 33 is also discharged to dissipate the heat of the battery pack 30 .

[0033] Furthermore, the lower bottom wall 320 has an inwardly recessed groove 325 and several raised arc-shaped ribs 326. The inner side of the arc-shaped rib 326 is sleeved on the outer side of the battery cell 33, and the arc-shaped rib 326 is provided with an air port 327. The air flow between the battery cells 33 passes through the air port 327 and is also connected to the air channel, so as to facilitate the heat discharge between the battery cells 33. The end of the above-mentioned groove 325 is adjacent to the above-mentioned air port 327, which is more conducive to the heat discharge of the battery cell 33. In the present embodiment, the above-mentioned groove 325 is arranged horizontally, and the two ends are connected with the air port 327.

[0034] The battery pack 30 has a bracket 60 located in the base 32, the bracket 60 has a pad 61 and a support portion 62 protruding from the pad, the pad 61 has a groove 63 facing the lower bottom wall 320, the support portion 62 has a support arc surface 64, the support arc surface 64 abuts against the outer peripheral surface of the battery cell, and the groove 63 is connected to the air channel I. In this embodiment, the support arc surface 64 is arranged in four, and respectively cooperates with the outer surface of the battery cell 33, clamping the battery cell 33 between the support arc surface 64 and the above-mentioned arc-shaped rib 326, providing a stable and compact battery pack. The bracket 60 has a through hole 65 that passes through the pad 61 and the support portion 62, and the through hole 65 is connected to the groove 63, the inner cavity 310 and the air channel.

[0035] The battery pack 30 has a sponge pad 70 located between the battery cell 33 and the lower bottom wall 320. The sponge pad 70 has a notch 71 connected to the groove 63. The sponge pad has a shock-absorbing effect on the battery cell to prevent the battery cell from being impacted by falling and causing explosion. In addition, the setting of the notch 71 further leads the heat at both ends of the battery cell 33 out through the notch 71.

[0036] The arc-shaped ribs 326 are evenly distributed on the bottom wall 320 in four pieces to facilitate the positioning of the four battery cells 33. Compared with the prior art, the present invention directly positions the battery cells 33 through the base 32 without providing an outer frame for fixing the battery cells, so that the distance H from the outer surface of the battery cell 33 to the inner side of the base 32 is 2-2.5 mm, which greatly reduces the diameter of the battery pack 30 and provides a small and delicate handle 102 structure.

[0037] The present invention directly installs and positions the battery cell 33 on the base 32, without the need to additionally set up an outer frame covering the outer periphery of the battery cell, thereby greatly reducing the diameter of the battery pack and providing a miniaturized, thin-handled handheld tool. Furthermore, the upper shell 31 and the base 32 are provided with two sections to cover the battery cell 33, and a narrow groove 312 is provided around the upper shell 31, thereby forming an air passage interconnected by the terminal insertion port 311, the narrow groove 312 and the opening 324, and the heat in the battery pack 30 is discharged from the body through the air passage I to prevent the problem of excessive temperature of the battery pack. At the same time, the two-section structure also prevents water and other media from entering the battery pack 30 to cause a short circuit. Therefore, the embodiment of the present invention not only realizes the miniaturization of the handle, but also can discharge the heat of the battery pack buried in the handle from the body, greatly reducing the heat dissipation of the battery pack.

[0038] The present invention is not limited to the above specific embodiments. A person skilled in the art can easily understand that there are many alternatives for the present invention for a rechargeable electric tool without departing from the principle and scope of the present invention. The protection scope of the present invention shall be subject to the content of the claims.

Claims

1. A rechargeable electric tool, comprising a housing, a motor fixed on the housing, and a battery pack inserted into the housing, the battery pack providing power to the motor, the housing having an outer shell and a handle connected to the outer shell, the motor being installed in the outer shell, and the battery pack being inserted into the handle; characterized in that: The battery pack comprises an upper shell inserted into the handle, a base, a battery cell accommodated in the upper shell and the base, and a bracket located in the base, the bracket having a supporting portion, the supporting arc surface of the supporting portion abutting against the outer peripheral surface of the battery cell, the upper shell having an inner cavity for mounting a circuit board, a terminal insertion port provided at one end adjacent to the circuit board, and a plurality of narrow grooves provided at the side wall of the other end, the terminal insertion port and the narrow grooves being communicated with the inner cavity respectively; the inner cavity depth of the upper shell is less than the length of the battery cell, when the battery cell is installed in the inner cavity and the protruding portion is accommodated in the base, and there is a gap between the battery cell and the inner cavity, and the base has a lower bottom The invention relates to a terminal block comprising a first end portion and a second end portion of the battery cell, wherein the first end portion and the second end portion are provided with a plurality of protruding arc-shaped ribs, the arc-shaped ribs being sleeved on the outer side of the battery cell, and the arc-shaped ribs being provided with air ports, and the air flow between the battery cells is connected to the air channel through the air ports.

2. The rechargeable electric tool according to claim 1, characterized in that: The lower bottom wall has an inwardly recessed channel, the end of which is adjacent to the air port and communicated with the air port.

3. The rechargeable electric tool according to claim 1, characterized in that: The bracket has a pad, the support portion protrudes from the pad, and the pad has a groove facing the lower bottom wall, and the groove is communicated with the air channel.

4. The rechargeable electric tool according to claim 3, characterized in that: The supporting arc surfaces are arranged in four forms and are respectively matched with the outer surfaces of the battery core.

5. The rechargeable electric tool according to claim 3 or 4, characterized in that: The bracket has a through hole penetrating the pad and the support portion, and the through hole is communicated with the inner cavity and the groove.

6. The rechargeable electric tool according to claim 5, characterized in that: The battery pack has a sponge pad located between the battery core and the lower bottom wall, and the sponge pad has a notch communicated with the groove.

7. The rechargeable electric tool according to claim 1, characterized in that: The arc-shaped ribs are divided into four and evenly distributed on the lower bottom wall.

8. The rechargeable electric tool according to claim 1, characterized in that: The upper shell has a buckling portion, the base has a snapping portion, and the snapping portion is snapped into a buckling groove of the buckling portion.

9. The rechargeable electric tool according to claim 1, characterized in that: The distance from the surface of the battery cell to the inner side of the base is 2-2.5 mm.

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