阅读说明：本技术 一种电动工具数字扭矩传感器和电动工具 (Electric tool digital torque sensor and electric tool ) 是由 王林峰 于 2021-07-27 设计创作，主要内容包括：本发明提供了一种电动工具数字扭矩传感器和电动工具,该电动工具数字扭矩传感器包括弹性体、应变计、FPC、数字PCB和电缆组件,所述FPC分别电连接所述应变计和电缆组件,所述电缆组件还与所述数字PCB电连接,所述应变计、FPC和数字PCB设置在所述弹性体上,所述弹性体中设置有容许电机的传动轴穿过的通孔,所述弹性体的一端部与所述电机的传动轴通过行星轮系连接。本发明提供的扭矩传感器集成了数字PCB,并且嵌入在电动工具中,在电机旋转时,扭矩传感器感应到扭矩,产生信号变化,并将模拟信号转化成数字变化,实现了即时数字化跟踪,具有抗干扰、高精度、轻盈小巧的特点。(The invention provides an electric tool digital torque sensor and an electric tool, the electric tool digital torque sensor comprises an elastic body, a strain gauge, an FPC, a digital PCB and a cable assembly, wherein the FPC is electrically connected with the strain gauge and the cable assembly respectively, the cable assembly is also electrically connected with the digital PCB, the strain gauge, the FPC and the digital PCB are arranged on the elastic body, a through hole allowing a transmission shaft of a motor to penetrate through is arranged in the elastic body, and one end part of the elastic body is connected with the transmission shaft of the motor through a planetary gear train. The torque sensor provided by the invention integrates the digital PCB and is embedded in the electric tool, when the motor rotates, the torque sensor senses the torque, generates signal change and converts an analog signal into digital change, so that the instant digital tracking is realized, and the torque sensor has the characteristics of interference resistance, high precision, lightness and small size.)

1. A power tool digital torque sensor, comprising: the strain gauge, the FPC and the digital PCB are arranged on the elastic body, a through hole allowing a transmission shaft of a motor to penetrate through is formed in the elastic body, and one end of the elastic body is connected with the transmission shaft of the motor through a planetary gear train.

2. A power tool digital torque transducer according to claim 1 wherein: the planetary gear train comprises a gear ring, a sun gear and three planetary gears, wherein the sun gear is concentrically arranged with the gear ring, the three planetary gears are simultaneously matched with internal teeth on the inner wall of the gear ring and external teeth on the sun gear, a transmission shaft of a motor of the electric tool is connected with the sun gear, a connecting sleeve also extends along the axial direction of the gear ring, and the connecting sleeve is sleeved with the outer part of one end part of the elastic body.

3. A power tool digital torque transducer according to claim 2 wherein: the elastomer includes first connecting portion, second connecting portion and connects the portion of meeting an emergency of first connecting portion and second connecting portion, install on the first connecting portion digital PCB, the second connecting portion with the connecting sleeve cup joints, strainometer, FPC attach respectively on the outer wall of the portion of meeting an emergency, be formed with in first connecting portion, second connecting portion and the portion of meeting an emergency the through-hole.

4. A power tool digital torque transducer according to claim 3 wherein: the first connecting portion and the second connecting portion are of hollow flat cylindrical structures, the strain portion is of a hollow long cylindrical structure, and the diameters of the first connecting portion and the second connecting portion are respectively larger than the diameter of the strain portion.

5. A power tool digital torque transducer according to claim 3 wherein: and a sealant is arranged around the periphery of the strain part.

6. A power tool digital torque transducer according to claim 3 wherein: the end face of the first connecting portion is provided with a support, and the digital PCB is installed on the support.

7. A power tool digital torque transducer according to claim 6 wherein: one end face of the first connecting portion, which is far away from the strain portion, is provided with a clamping groove, one end face of the support is provided with a clamping block, the support is clamped with the connecting portion through the matching of the clamping groove and the clamping block, and the center of the support is provided with an avoiding hole allowing the transmission shaft of the motor to penetrate.

8. A power tool digital torque transducer according to claim 6 wherein: the support is kept away from be provided with a plurality of reference columns that the annular was arranged on the terminal surface of first connecting portion, digital PCB cover is located a plurality of on the reference column, the tip of reference column still is provided with prevents the barb that digital PCB deviates from.

9. A power tool digital torque transducer according to claim 3 wherein: the diameter of the elastomer is 20-24 mm, and the height of the elastomer is 30-40 mm; and/or the elastomer is made of aluminum alloy.

10. An electric power tool characterized in that: the digital torque sensor of the electric tool is embedded into the shell, one end part of the elastic body is connected with a transmission shaft of the motor through the planetary gear train, the other end part of the elastic body is fixedly connected with the shell, and the tail end of the transmission shaft of the motor is connected with the working head.

Technical Field

The invention relates to the technical field of sensors, in particular to a digital torque sensor of an electric tool and the electric tool.

Background

With the development of global science and technology digitization, in the industrial field, more efficient and accurate sensors can provide more accurate and directional data support for production personnel, and also provide simple and convenient visual production tools for engineering personnel, such as the efficiency of an electric tool can be known in real time.

The existing electric tool has low mechanical torque control precision, cannot detect the magnitude of the torque in real time, and a long cable not only limits the application of the electric tool but also easily causes safety accidents.

Disclosure of Invention

The invention aims to provide a digital torque sensor of an electric tool and the electric tool, so as to overcome the defects of the prior art.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the invention discloses a digital torque sensor of an electric tool, which comprises an elastic body, a strain gauge, an FPC (flexible printed circuit), a digital PCB (printed circuit board) and a cable assembly, wherein the FPC is electrically connected with the strain gauge and the cable assembly respectively, the cable assembly is also electrically connected with the digital PCB, the strain gauge, the FPC and the digital PCB are arranged on the elastic body, a through hole allowing a transmission shaft of a motor to pass through is arranged in the elastic body, and one end part of the elastic body is connected with the transmission shaft of the motor through a planetary gear train.

Preferably, the planetary gear train includes a gear ring, a sun gear concentrically disposed with the gear ring, and three planetary gears simultaneously engaged with internal teeth on an inner wall of the gear ring and external teeth on the sun gear, a transmission shaft of a motor of the electric tool is connected with the sun gear, the gear ring further extends along an axial direction thereof with a connecting sleeve, and the connecting sleeve is sleeved with an outer portion of one end portion of the elastic body.

Further preferably, the elastomer includes first connecting portion, second connecting portion and connects the portion of meeting an emergency of first connecting portion and second connecting portion, install on the first connecting portion digital PCB, the second connecting portion with connecting sleeve cup joints, strainometer, FPC attach respectively on the outer wall of the portion of meeting an emergency, be formed with in first connecting portion, second connecting portion and the portion of meeting an emergency the through-hole.

Further preferably, the first connecting portion and the second connecting portion are of hollow flat cylindrical structures, the strain portion is of a hollow long cylindrical structure, and the diameters of the first connecting portion and the second connecting portion are respectively larger than the diameter of the strain portion.

More preferably, a sealant is disposed around the outer periphery of the strain portion.

Further preferably, a bracket is arranged on the end face of the first connecting part, and the digital PCB is mounted on the bracket.

Further preferably, an end face of the first connecting portion, which is far away from the strain portion, is provided with a clamping groove, an end face of the bracket is provided with a clamping block, the bracket is clamped with the connecting portion through the matching of the clamping groove and the clamping block, and the center of the bracket is provided with an avoiding hole allowing the transmission shaft of the motor to pass through.

Further preferably, the support is far away from be provided with a plurality of reference columns that the annular was arranged on the terminal surface of first connecting portion, digit PCB cover is located a plurality of on the reference column, the tip of reference column still is provided with and prevents the barb that digit PCB deviates from.

Preferably, the diameter of the elastomer is 20-24 mm, and the height of the elastomer is 30-40 mm.

Preferably, the elastomer is made of aluminum alloy.

The invention also provides an electric tool, which comprises a shell, a working head, the motor and the electric tool digital torque sensor, wherein the electric tool digital torque sensor is embedded into the shell, one end part of the elastic body is connected with a transmission shaft of the motor through the planetary gear train, the other end part of the elastic body is fixedly connected with the shell, and the tail end of the transmission shaft of the motor is connected with the working head.

Compared with the prior art, the invention has the advantages that:

1) the torque sensor provided by the invention integrates the digital PCB and is embedded in the electric tool, when the motor rotates, the torque sensor senses the torque, generates signal change and converts an analog signal into digital change, so that the instant digital tracking is realized, and the torque sensor has the characteristics of interference resistance, high precision, lightness and small size.

2) The elastomer material provided by the invention adopts the aluminum alloy, so that the torque requirement is ensured, and the light weight of the sensor can be realized.

3) The invention provides a strain gauge with high precision, which ensures the precision of the sensor;

4) the diameter of the elastic body of the sensor is 20-24 mm, the height of the elastic body is 30-40 mm, and the elastic body is light and small.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below.

FIG. 1 is a schematic structural diagram of a digital torque sensor of a power tool according to an embodiment of the present invention;

FIG. 2 is a front view of a digital torque sensor of the power tool disclosed in the embodiments of the present invention;

FIG. 3 is a schematic view of the structure of the elastomer and the stent disclosed in the embodiment of the invention;

FIG. 4 is a schematic structural diagram of an elastomer disclosed in an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a planetary gear train disclosed by the embodiment of the invention;

fig. 6 is a schematic structural view of a main portion of the electric power tool disclosed in the embodiment of the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to fig. 1-6, the embodiment of the invention discloses a digital torque sensor of an electric tool, which comprises an elastic body 1, a strain gauge 2, an FPC3, a digital PCB4 and a cable assembly, wherein the FPC3 is respectively and electrically connected with the strain gauge 2 and the cable assembly, the cable assembly is also electrically connected with the digital PCB4, the strain gauge 2, the FPC3 and the digital PCB4 are arranged on the elastic body 1, a through hole 14 allowing a transmission shaft a1 of a motor a to pass through is arranged in the elastic body 1, and one end of the elastic body 1 is connected with the transmission shaft a1 of the motor a through a planetary gear train b.

The planetary gear train b comprises a gear ring b1, a sun gear b2 arranged concentrically with the gear ring b1, and three planetary gears b3 matched with internal teeth on the inner wall of the gear ring b1 and external teeth on the sun gear b2 at the same time, wherein a transmission shaft a1 of a motor a of the electric tool is connected with the sun gear b2, a connecting sleeve extends along the axial direction of the gear ring b1, and the connecting sleeve is sleeved with the outer portion of one end portion of the elastic body 1.

Elastomer 1 includes first connecting portion 11, second connecting portion 12 and connects the portion of meeting an emergency 13 of first connecting portion 11 and second connecting portion 12, installs digital PCB4 on the first connecting portion 11, and second connecting portion 12 cup joints with the connecting sleeve, and strainometer 2, FPC3 are attached respectively on the outer wall of portion of meeting an emergency 13, are formed with the through-hole in first connecting portion 11, second connecting portion 12 and the portion of meeting an emergency 13.

The first connecting portion 11 and the second connecting portion 12 are of hollow flat cylindrical structures, the strain portion 13 is of a hollow long cylindrical structure, and the diameters of the first connecting portion 11 and the second connecting portion 12 are respectively larger than the diameter of the strain portion 13.

The periphery of the strain part 13 is provided with a sealant 5 in a surrounding manner, and the sealant 5 plays a role in protecting the strain gauge 2 and the FPC3 after being sealed.

A bracket 6 is provided on an end surface of the first connection part 11, and the digital PCB4 is mounted on the bracket 6. An end face of the first connecting portion 11, which is far away from the strain portion 13, is provided with a clamping groove 111, an end face of the bracket 6 is provided with a clamping block 61, the bracket 6 and the first connecting portion 11 are clamped by matching of the clamping groove 111 and the clamping block 61, and the center of the bracket 6 is provided with an avoiding hole 64 allowing a transmission shaft a1 of the motor a to pass through. The assembly of the elastic body 1 and the bracket 6 is realized through the clamping groove 111 and the clamping block 61, and the assembly is convenient and fast.

The end face of the bracket 6 far away from the first connecting portion 11 is provided with a plurality of positioning posts 62 arranged in an annular shape, the digital PCB4 is sleeved on the positioning posts 62, and the end portion of the positioning posts 62 is further provided with barbs 63 for preventing the digital PCB4 from coming off. The base plate of digital PCB4 is provided with the round hole in the middle of, directly overlaps digital PCB4 on reference column 62 through the round hole, and barb 63 can prevent that digital PCB4 from deviating from on reference column 62.

The diameter of elastomer 1 is 20 ~ 24mm, and highly is 30 ~ 40mm, and elastomer 1 is light small and exquisite like this. The elastic body 1 is made of aluminum alloy, the torque requirement is guaranteed by the aluminum alloy, and the light weight of the sensor can be realized.

Referring to fig. 5 to 6, the embodiment of the invention further provides an electric tool, which includes a housing b, a working head, a motor a, and the above-mentioned electric tool digital torque sensor, the electric tool digital torque sensor is embedded in the housing b, one end of the elastic body 1 is connected with the transmission shaft a1 of the motor a through a planetary gear train b, the other end of the elastic body 1 is fixedly connected with the housing b, and the end of the transmission shaft a1 of the motor a is connected with the working head.

Specifically, because the motor a is unstable due to the fact that the transmission shaft a1 of the motor a is too long, in this embodiment, a T-shaped front end shaft d for extending the transmission shaft a1 of the motor a is further used, the transmission shaft a1 of the motor a passes through a through hole in the elastic body 1 of the sensor, the transmission shaft a1 of the motor a passes through the through hole and then is connected with the sun gear b2, the three planet gears b3 are respectively sleeved with the sun gear b2, the ring gear b1, the planet gears b3, the sun gear b2 and the ring gear b1 to form a planet gear train b, the ring gear b1 is sleeved with the second connecting portion of the elastic body 1 through an extension portion of the ring gear b1 and a connecting sleeve, connecting shafts e for connecting the three planet gears b3 are respectively and fixedly arranged on the long end face of the front end shaft d, the end of the front end shaft d is connected with a working head, the outer peripheral surface of the first connecting portion of the elastic body 1 is fixedly connected with the inner wall of the housing (fixedly connected by screws), and the motor a, a, The planetary gear train b and the front end shaft d are both arranged in a shell b of the electric tool, and the working head is exposed out of the shell b of the electric tool. The electric tool may be an electric screw machine, an electric torque wrench, or the like with a motor a.

The torque sensor provided by the embodiment of the invention integrates the digital PCB4 and is embedded in an electric tool, when the motor a rotates, the transmission shaft a1 of the motor a transmits the torque to the elastic body 1 of the torque sensor through the planetary gear train b, the torque sensor senses the torque, generates signal change and converts an analog signal into digital change, so that the instant digital tracking is realized, and the torque sensor has the characteristics of interference resistance, high precision, lightness and small size.

Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.