JP7769669B2 - Torque detection device for power tools - Google Patents

Description

The present invention relates to power tools, and in particular to a torque detection device for power tools.

Currently, power tools equipped with torque sensors can be used to detect torque and transmit a signal when a predetermined torque is reached, controlling the power unit to stop operation.

In addition, torque sensors in general power tools are typically installed on the transmission mechanism, and as the transmission mechanism operates, the torque sensor is left rotating for long periods of time, causing problems such as broken wires and poor contact, affecting electrical connections and potentially damaging the power tool. Furthermore, when the power tool is in operation, vibrations or deformations occur in the transmission mechanism that connects the tool head, further affecting the torque values detected by the installed torque sensor and reducing the accuracy of the torque sensor.

In light of this, the inventor conducted extensive research into the above-mentioned conventional technology and, by applying academic theory, worked hard to resolve the above-mentioned issues, thereby achieving his goal of improvement.

One object of the present invention is to provide a torque indicator for a power tool, in which the torque lever is installed within the handle and perpendicular to the power unit, so that torque detection is not affected by vibrations from the power unit and an accurate torque value is provided.

One object of the present invention is to provide a torque indicator for a power tool that is easier to assemble because the torque lever and torque sensor are mounted on the handle of the housing, preventing the torque sensor from rotating along with the power unit and avoiding problems such as broken wires and poor contact.

To achieve the above objective, the torque indicating device for a power tool of the present invention includes a housing, a power unit, a bearing set, a torque lever, and a torque sensor. The housing includes a main body and a handle connected perpendicularly to one side of the main body. The power unit is installed within the main body and includes a power unit and a protective cover fitted to the power unit. The bearing set is installed between the protective cover and the housing, allowing the power unit to rotate relative to the housing. The torque lever is installed within the handle and abuts against the protective cover. The torque lever is installed perpendicular to the power unit, and the torque sensor is installed on the torque lever.

Compared to prior art, the power tool of the present invention has a torque lever and torque sensor mounted on the handle portion of the housing, preventing the torque sensor from rotating along with the power unit and avoiding problems such as broken wires and poor contact, improving assembly convenience. Furthermore, in the present invention, the torque sensor is mounted on the torque lever on one side perpendicular to the power unit, preventing the torque sensor from being affected by vibrations or deformation from external tool components, thereby providing accurate torque values and improving practicality in use.

1 is a schematic three-dimensional external view of a power tool according to the present invention; 1 is a schematic three-dimensional external view of a torque detection device according to the present invention. 1 is a schematic exploded view of a torque detection device according to the present invention. 1 is a combined cross-sectional view of a power tool according to the present invention taken along both sides; 1 is a combined cross-sectional view of a power tool according to the present invention taken along both sides; 1 is a schematic diagram of an application of a power tool according to the present invention;

The detailed description and technical contents of the present invention are described below with reference to the accompanying drawings. The attached drawings are provided for reference purposes only and are not intended to limit the present invention.

1 to 3 are a three-dimensional schematic view of a power tool, a three-dimensional schematic view of a torque detection device, and a three-dimensional exploded schematic view of a torque detection device, respectively, according to the present invention. The present invention is a torque detection device for a power tool. The power tool 1 includes a housing 10, a power unit 20, a bearing set 30, a torque lever 40, and a torque sensor 50. The power unit 20 is mounted within the housing 10. The bearing set 30 is installed between the power unit 20 and the housing 10. The torque lever 40 is connected to the torque sensor 50 and is installed perpendicular to the power unit 20. The power tool 1 measures torque via the torque sensor 50 and can control the operation of the power unit 20 accordingly. The structures of the power tool 1 and its torque detection device are described in more detail below.

The housing 10 includes a main body 11 and a handle 12 that is vertically connected to one side of the main body 11. In this embodiment, the housing 10 is installed in a T-shape.

The power unit 20 is installed within the main body 10. The power unit 20 includes a power unit 21 and a protective cover 22 that fits over the power unit 21. A drive shaft 211 is installed in the power unit 21.

In this embodiment, the power unit 21 is an electric motor that uses a battery as a power source to rotate the drive shaft 211. However, in actual implementation, the power unit 21 can also be installed as an air motor that uses compressed air as a power source to rotate the drive shaft 211.

The bearing set 30 is installed between the protective cover 22 and the housing 10, thereby allowing the power unit 21 (together with the protective cover 22) to rotate relative to the housing 10.

An outer annular rib 220 is molded on the outer surface of the protective cover 22. The protective cover 22 also has opposing front and rear protective cover sides 221 and 222. A plurality of front ratchet pawls 2211 are provided on the edge of the front protective cover 221. A plurality of rear ratchet pawls 2221 are provided on the edge of the rear protective cover 222.

In one embodiment of the present invention, the power unit 20 further includes a pair of motor fixing pieces 23. The pair of motor fixing pieces 23 includes a front fixing piece 231 and a rear fixing piece 232 installed on opposite sides of the protective cover 22. A plurality of front convex pieces 2311 are installed at intervals around the periphery of the front fixing piece 231. A plurality of rear convex pieces 2321 are installed at intervals around the periphery of the rear fixing piece 232.

In addition, the power unit 20 further includes a plurality of locking members 24. A plurality of first locking holes 2310 are formed in the front fixing piece 231, and a plurality of corresponding second locking holes 210 are formed in the power unit 21. The front fixing piece 231 is fixed to the power unit 21 by being inserted through the first locking holes 2310 and the second locking holes 210 via the locking members 24.

Specifically, the front fixed pieces 231 engage with the front ratchet pawls 2211 of the protective cover 22 via their front convex pieces 2311, and are positioned at one end of the front side 221 of the protective cover. Furthermore, the rear fixed pieces 232 engage with the rear ratchet pawls 2221 of the protective cover 22 via their rear convex pieces 2321, and are positioned at one end of the rear side 222 of the protective cover.

The bearing set 30 also includes a front bearing 31 and a rear bearing 32 installed on either side of the outer annular rib 220. The torque lever 40 is installed within the handle 12 and abuts against the protective cover 22, with the torque lever 40 and the power unit 21 installed perpendicularly.

Alternatively, the torque sensor 50 can be installed as a strain gauge mounted on the torque lever 40. The main principle of the torque sensor 50 (strain gauge) is that when the torque lever 40 is bent (deformed), a change in electrical resistance occurs. This change in electrical resistance generates a signal, which is then calculated to generate a corresponding torque value.

More specifically, the torque lever 40 includes a base column 41 and a platform 42 connected to the base column 41. The torque sensor 50 is installed on the side of the platform 42. In this embodiment, the platform 42 has an abutment surface 421. The platform 42 abuts against the outer annular rib 220 of the protective cover 22 via the abutment surface 421. In addition, an outer annular flat surface 2201 is installed corresponding to the outer annular rib 220. In other words, the abutment surface 421 of the torque lever 40 is attached to the outer annular flat surface 2201 of the protective cover 22.

It should be noted here that in this embodiment, the torque lever 40 is fixed to the protective cover 22 via the outer annular rib 220. The provision of the outer annular rib 220 increases the structural strength of the protective cover 22, preventing deformation of the protective cover 22 under rotational pressure, ensuring that the torque sensor 50 on the torque lever 40 can accurately detect the amount of deformation and generate a signal.

Referring further to Figures 4 and 5, which are combined cross-sectional views of the power tool of the present invention. As shown, the power unit 20 of the present invention is installed within the main body 11. The bearing set 30 is installed between the protective cover 22 and the housing 10. The pair of motor fixing pieces 23 are installed on opposite sides of the power unit 21. Additionally, the torque lever 40 is installed within the handle 12 and abuts against the protective cover 22, and the torque sensor 50 is fixed on the platform 42 of the torque lever 40.

It should be noted here that the interior of the handle 12 includes a positioning space 121 and an electrical space 122 that are in communication with each other. The base column 41 of the torque lever 40 is engaged within the positioning space 121. The platform 42 of the torque lever 40 extends through the electrical space 122, with an attachment gap 122' remaining.

Continuing to refer to FIG. 6, it is a schematic diagram of the application of the power tool of the present invention. The power tool 1 of the present invention further includes a transmission 60. The transmission 60 is connected to the drive shaft 211 of the power body 21 to provide the required rotational output. Furthermore, the power tool 1 further includes a battery 70 and a control board 80. The battery 70 and the control board 80 are installed in the mounting gap 122', and the control board 80 electrically connects the power body 21 and the torque sensor 50.

When the power unit 21 is activated (operated) and receives an external blocking force, a reversing force is generated in the power unit 21. The power unit 21 transmits the reversing force to the protective cover 22, causing the protective cover 22 to rotate. When the protective cover 22 rotates, the torque lever 40 is also rotated, causing deformation of the torque lever 40. As a result, the torque sensor 50 on the torque lever 40 receives the amount of deformation and generates a signal.

At that time, the torque sensor 50 transmits a signal to the control plate 80 to immediately stop the operation of the power unit 21. Furthermore, when the power tool 1 is operating, the power unit 21 is likely to be subjected to vibrations from external tool components as power is transmitted, which affects the torque value. The torque sensor 50 of the present invention is installed on the torque lever 40 on one side perpendicular to the power unit 21. Because the torque lever 40 is not a power transmission element, it is not affected by the vibrations of the power unit 21, and the torque sensor 50 can perform torque detection and provide an accurate torque value.

The above description is merely a preferred embodiment of the present invention and does not define the scope of the patent claims of the present invention. All other equivalent modifications that utilize the patent concepts of this invention are also considered to fall within the scope of the patent claims of the present invention.

REFERENCE SIGNS LIST 1 power tool 10 housing 11 main body 12 handle 121 positioning space 122 electrical space 122' mounting gap 20 power unit 21 power unit main body 210 second locking hole 211 drive shaft 22 protective cover 220 outer annular rib 2201 outer annular flat surface 221 front side of protective cover 2211 front ratchet pawl 222 rear side of protective cover 2221 rear ratchet pawl 23 motor fixing piece 231 front fixing piece 2310 first locking hole 2311 front convex piece 232 rear fixing piece 2321 rear convex piece 24 locking member 30 bearing set 31 front bearing 32 rear bearing 40 torque lever 41 base column 42 platform 421 contact surface 50 torque sensor 60 transmission 70 Battery 80 Control board

Claims (10)

a housing (10) including a body (11) and a handle (12) connected to the body (11);
a power unit (20) installed in the main body (11) and including a power unit (21 ) having a drive shaft (211) and a protective cover (22) fitted to the power unit (21);
a bearing set (30) that is installed between the protective cover (22) and the main body ( 11 ) to allow the power main body (21) to rotate relative to the housing (10);
a torque lever (40) that is installed in the handle (12), abuts against the protective cover (22), and is installed perpendicular to the axial direction of the drive shaft (211) of the power body (21);
and a torque sensor (50) installed on the torque lever (40). 2. The torque detection device for a power tool according to claim 1, wherein an outer annular rib (220) is molded on the protective cover (22), and the bearing set (30) includes a first bearing (31) and a second bearing (32) facing each other across the outer annular rib (220). 2. The torque detection device for a power tool as described in claim 1, wherein the protective cover (22) has a first protective cover (221) and a second protective cover (222) facing each other , and a plurality of first ratchet pawls (2211) are provided on the edge of the first protective cover (221), and a plurality of second ratchet pawls (2221) are provided on the edge of the second protective cover (222). The torque detection device for a power tool as described in claim 3, wherein the power unit (20) further includes a pair of motor fixing pieces (23), the pair of motor fixing pieces (23) including a first fixing piece (231) and a second fixing piece (232) that abut against the protective cover (22), and a plurality of first convex pieces (2311) are arranged at intervals on the periphery of the first fixing piece (231), and a plurality of second convex pieces (2321) are arranged at intervals on the periphery of the second fixing piece (232). A torque detection device for a power tool as described in claim 4, wherein the first fixed piece (231) is positioned at one end of the first protective cover (221) by engaging with the first ratchet pawl (2211) via their first protrusion (2311), and the second fixed piece (232) is positioned at one end of the second protective cover (222) by engaging with the second ratchet pawl (2221) via their second protrusion (2321). 5. The torque detection device for a power tool according to claim 4, wherein the power unit (20) further includes a plurality of locking members (24), the first fixing piece (231) has a plurality of first locking holes (2310), the power body (21) has a plurality of second locking holes (210), and the first fixing piece (231) is fixed on the power body (21) by being inserted through the first locking holes (2310) and the second locking holes (210) via the locking members (24). 3. The torque detection device for a power tool according to claim 2, wherein the torque lever (40) includes a base column (41) and a platform (42) connected to the base column (41), and the torque sensor (50) is installed on the platform (42). A torque detection device for a power tool as described in claim 7, wherein an abutment surface (421) is provided on the platform (42), and the platform (42) abuts against the outer annular rib (220) of the protective cover (22) via the abutment surface (421). The torque detection device for a power tool according to claim 7, wherein the handle (12) includes a positioning space (121) and an electrical space (122) that communicate with each other, the base column (41) is engaged within the positioning space (121), the platform (42) extends through the electrical space (122), and an attachment gap (122') is reserved. 10. The torque detection device for a power tool according to claim 9, further comprising a battery (70) and a control plate (80), the battery (70) and the control plate (80) being installed in the mounting gap (122'), and the control plate (80) electrically connecting the power body (21) and the torque sensor (50).