TWI674399B - Calibration mechanism for force/torque sensor - Google Patents

Abstract

A correction mechanism for a force / torque sensor is used to correct a force / torque sensor. The correction mechanism includes a base, a jig, an axial force applying unit and a link group. The sensor is fixed between the base and the jig. The axial force applying unit and the jig are respectively connected to two ends of the connecting rod group. A motor of the axial force applying unit passes the shaft. A load element of the force applying unit, the connecting rod group and the jig are used to apply force to the force / torque sensor, and the load element of the axial force applying unit is used to obtain a force data by the load The force data obtained by the source collates a force data of the force / torque sensor.

Description

Calibration mechanism for force / torque sensor

The invention relates to a correction mechanism of a force / torque sensor, which is used to calibrate a force data of a force / torque sensor.

In automated factories, robot arms are used for processing and assembly. Therefore, controlling the precise force of robot arms is a very important technology. Usually, sensors are installed in robot arms to sense the robot arms for processing and assembly. Time, whether the sensor can accurately sense the force or force from different directions of the robot arm must be adjusted to avoid the collision of the robot arm due to inaccurate sensors.

A calibration mechanism of a force / torque sensor of the present invention is mainly used to calibrate a force data of a force / torque sensor.

A calibration mechanism for a force / torque sensor according to the present invention includes a base, a jig, an axial force applying unit, and a connecting rod group. The base is used to fix a force / torque sensor. The force / torque sensor is combined with the force / torque sensor so that the force / torque sensor is clamped and fixed between the base and the jig. The axial force applying unit has a motor and a load cell. The load cell is combined with the motor, the link group has a pivot base, a linkage rod and a positioning base, the pivot base is coupled with the jig, the positioning base is coupled with the load cell, a A first end portion is pivotally connected to the pivot base, a second end portion of the linkage rod is coupled to the positioning base, and the motor drives the treatment by the load cell, the positioning base, the linkage rod, and the pivot base. To apply force to the force / torque sensor clamped and fixed between the base and the jig to obtain a force data of the force / torque sensor and to obtain the load element A force data.

The correction mechanism of the present invention can perform compression, tension, and torsion tests on the force / torque sensor such as compression, tension, and torsion to obtain the force data and the load element of the force / torque sensor. The load data to adjust the load element.

Please refer to FIGS. 1 and 2, a calibration mechanism 100 for a force / torque sensor according to the present invention is used to detect a force / torque sensor 200 to correct a force of the force / torque sensor 200. data.

Please refer to FIGS. 1 and 2. In this embodiment, the two correction mechanisms 100 are symmetrically disposed on the relative two measurements of the force / torque sensor 200 to detect and correct the force / torque sensor 200. However, this is not a limitation, and if necessary, one or two or more correction mechanisms 100 may perform detection and correction on the force / torque sensor 200.

Please refer to FIGS. 1 and 2. The correction mechanism 100 includes a base 110, a jig 120, an axial force applying unit 130, and a link group 140. The force / torque sensor 200 is fixed to the base. A bearing surface 111 of 110, the jig 120 is combined with the force / torque sensor 200, so that the force / torque sensor 200 is clamped and fixed between the base 110 and the jig 120, at In this embodiment, the force / torque sensor 200 is provided with at least one strain gauge, and the force data of the force / torque sensor 200 obtained by the strain gauge is not limited.

Please refer to FIGS. 1 and 2. The axial force applying unit 130 has a motor 131 and a load element 132. The load element 132 is combined with the motor 131. In this embodiment, the motor 131 is selected from a voice coil motor. (VCM), preferably, the calibration mechanism 100 further includes a first stage 150 and a first sliding group 160. The first stage 150 has a base 151 and a carrier plate 152. The first sliding group 160 There is a first rail 161 and a first slide base 162. The first slide base 162 is movably disposed on the first rail 161, and the first slide base 162 can slide along the first rail 161. The base 151 of the carrier 150 is coupled to the first slide 162 of the first sliding group 160. The carrier plate 152 is located between the motor 131 and the load element 132. In this embodiment, the motor 131 and the Load elements 132 are respectively coupled to two sides of the carrier plate 152. When the motor 131 is actuated, the first stage 150 moves along an axial force direction of the motor 131 and drives the load element 132 to move. The first stage 150 and the first sliding group 160 allow the load cell 132 to move smoothly along the axial force direction of the motor 131 so as to avoid To avoid unnecessary external force from affecting the sensing accuracy of the load cell 132, in this embodiment, the axial force application direction of the motor 131 is parallel to the bearing surface 111.

Please refer to FIGS. 1 and 2. The calibration mechanism 100 further includes a second carrier 170. The second carrier 170 has a first bearing portion 171 and a second bearing portion 172. A first rail 161 is disposed on the first bearing portion 171, and the first rail 161 is parallel to the axial force applying direction of the motor 131. The motor 131 is disposed on the second bearing portion 172. When a force is applied to the carrier plate 152 of the first carrier 150, the first carrier 150 and the first slide 162 are displaced along the first rail 161 provided on the first bearing portion 171.

Referring to FIGS. 1 and 2, the calibration mechanism 100 further includes an adjustment stage 190. The first bearing portion 171 of the second stage 170 is located between the first sliding group 160 and the adjustment stage 190. The adjustment stage 190 is coupled to the first bearing portion 171, and the adjustment stage 190 is used to adjust the second stage 170 to move in the axial force direction perpendicular to the motor 131.

Please refer to FIGS. 1 and 2. The link group 140 has a pivot base 141, a linkage rod 142 and a positioning base 143. The pivot base 141 is coupled to the jig 120, and the positioning base 143 is coupled to the load. Element 132, a first end portion 142a of the linkage lever 142 is pivotally connected to the pivot base 141, and a second end portion 142b of the linkage lever 142 is coupled to the positioning base 143. When the motor 131 is actuated, The load cell 132, the positioning base 143, the linkage rod 142, and the pivot base 141 drive the jig 120 to force and torque the clamped and fixed between the base 110 and the jig 120 The sensor 200 applies force to obtain the force data of the force / torque sensor 200 and a force data of the load element 132, and corrects the force / torque by the force data of the load element 132 The force data of the sensor 200, so that the force data of the force / torque sensor 200 is consistent with the force data of the load element 132.

Please refer to FIG. 1 and FIG. 2. In this embodiment, the first end portion 142 a of the linkage lever 142 is provided with a pivot joint 142 c, and the pivot joint 142 c is movably pivotally coupled to the pivot base 141. The joint 142c is selected from joints such as a cross joint, a ball joint, and a universal joint.

Please refer to FIGS. 1, 2 and 3. The positioning base 143 has a receiving groove 143 a and positioning plates 143 b respectively located on two sides of the receiving groove 143 a. Each of the positioning plates 143 b has at least one screw hole 143 c. The second end portion 142b of the rod 142 is disposed in the receiving groove 143a, and at least one bolt 143d is engaged with the screw hole 143c and abuts against the second end portion 142b of the linkage rod 142. Please refer to FIG. 3, In this embodiment, the receiving groove 143a has a height H, and the second end portion 142b of the link rod 142 has a thickness D, and the height H is greater than the thickness D.

Please refer to FIGS. 2 and 3. In this embodiment, the positioning base 143 further has an adjusting hole 143 e penetrating the positioning base 143, the adjusting hole 143 e communicates with the receiving groove 143 a, and a fixing member 180 passes through the receiving hole. A slot 143a is penetrated in the adjusting hole 143e, the fixing member 180 and the positioning seat 143 are fixed to the load element 132. In this embodiment, the fixing member 180 is a bolt, so that the positioning seat 143 is forced. A bolt head tighter than the bolt and the load element 132.

Please refer to FIGS. 2 and 3. In this embodiment, the adjusting hole 143e has an aperture O1, the fixing member 180 has an outer diameter O2, and the adjusting hole 143e has an aperture O1 larger than the outer diameter of the fixing member 180. O2.

Please refer to FIGS. 1, 2 and 4. Preferably, the correction mechanism 100 further includes a second sliding group 300. The second sliding group 300 has a second track 310 and a second slide 320. The slide 320 is movably disposed on the second track 310. The second slide 320 is used to set a measuring tool 400. The measuring tool 400 may be selected from a dial indicator, an optical measuring instrument, and the like. The track 310 is parallel to the axial urging direction of the motor 131.

Referring to FIG. 4, the measurement tool 400 is provided with the second slide base 320. The measurement tool 400 is used to measure a side wall of the linkage rod 142, and the second slide base 320 is moved to make the measurement tool 400 follow. The second sliding seat 320 is moved along the second track 310 to measure the linkage rod 142. When the linkage rod 142 and the axial force direction of the motor 131 are not parallel, the adjustment stage is used. 190 moves the second carrier 170 to cause the linkage lever 142 to swing laterally with the pivot joint 142c as a fulcrum until the linkage lever 142 is parallel to the axial force direction of the motor 131. Similarly, another amount The measuring tool 400 measures a top wall of the linkage lever 142. When the tilt angle of the linkage lever 142 with respect to the axial force direction of the motor 131 is large, the aperture O1 of the adjustment hole 143e is larger than the fixed The outer diameter O2 of the member 180 can be loosened, and the fixing member 180 can still be accommodated in the adjustment hole 143e. After that, the positioning base 143 is moved so that the positioning base 143 extends perpendicular to the axis. Move in the direction of force, and swing the link lever 142 with the pivot joint 142c as a fulcrum until the link When the lever 142 is parallel to the axial urging direction of the motor 131, or when the inclination angle of the linkage lever 142 with respect to the axial urging direction of the motor 131 is small, due to the height of the receiving groove 143a H is greater than the thickness D of the second end portion of the link lever 142, so the link lever 142 can be adjusted by the bolt 143d engaged with each of the screw holes 143c until the link lever 142 and the motor 131 The axial force application directions are parallel.

Please refer to FIGS. 2, 5 to 8, the force / torque sensor 200 is calibrated by the correction mechanism 100. In this embodiment, the force / torque sensor 200 has four crab-shaped feet. In FIG. 5, two correction mechanisms 100 are disposed symmetrically on opposite sides of the force / torque sensor 200 respectively, and a motor 131 applies a thrust force, and the other motor 131 exerts a pull force to the force / torque sensor 200. The torque sensor 200 generates a thrust correction force, or, referring to FIG. 6, the motor 131 of the correction mechanism 100 simultaneously applies a thrust force to generate a torque correction force to the force / torque sensor 200. Alternatively, referring to FIG. 7, the motor 131 of the calibration mechanism 100 applies a pulling force at the same time to generate a torque correction force for the force / torque sensor 200 to obtain the force / torque sensor 200. The force data and the force data of the load element 132.

Please refer to FIGS. 8 and 9, which are a second embodiment of the present invention. The difference from the first example is that the bearing surface 111 of the base 110 and the axial force direction of the motor 131 are perpendicular to each other. Ground, the motor 131 of the correction mechanism 100 applies a pushing force, or a pulling force, or a pushing force and a pulling force at the same time to generate a pressure or pulling force for the force / torque sensor 200. To obtain the force data of the force / torque sensor 200 and the force data of the load element 132.

The correction mechanism 100 performs compression, tension, and torsion tests on the force / torque sensor 200 such as compression, tension, and torsion to obtain the force data and the load of the force / torque sensor 200. The force data of the element 132 is used to adjust the load element 132 to increase the accuracy and stability of the force / torque sensor 200 and improve the reliability of the force / torque sensor 200.

The protection scope of the present invention shall be determined by the scope of the appended patent application. Any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the present invention. .

100‧‧‧ force / torque sensor correction mechanism

110‧‧‧ base

111‧‧‧bearing surface

120‧‧‧Jig

130‧‧‧ axial force application unit

131‧‧‧ Motor

132‧‧‧Loading Yuan

140‧‧‧ connecting rod set

141‧‧‧ Pivot

142‧‧‧Linking lever

142a‧‧‧first end

142b‧‧‧ second end

142c‧‧‧ pivot joint

143‧‧‧Positioning Block

143a‧‧‧Receiving slot

143b‧‧‧Positioning plate

143c‧‧‧Thread hole

143d‧‧‧bolt

143e‧‧‧adjustment hole

150‧‧‧ the first carrier

151‧‧‧base

152‧‧‧ Carrier Board

160‧‧‧The first sliding group

161‧‧‧First track

162‧‧‧First slide

170‧‧‧Second carrier

171‧‧‧First load

172‧‧‧Second loading section

180‧‧‧Fixture

190‧‧‧Adjust the carrier

200‧‧‧ Force / Torque Sensor

300‧‧‧Second sliding group

310‧‧‧Second Track

320‧‧‧Second Slide

400‧‧‧ measuring tools

H‧‧‧ height

D‧‧‧thickness

O1‧‧‧ aperture

O2‧‧‧ outer diameter

Figure 1: A perspective view of a correction mechanism according to a first embodiment of the present invention. Fig. 2: An exploded perspective view of a correction mechanism according to a first embodiment of the present invention. FIG. 3 is a partial cross-sectional view of a correction mechanism according to the first embodiment of the present invention. Fig. 4 is a perspective view of a correction mechanism according to the first embodiment of the present invention. Figures 5 to 7: Schematic diagrams of the operation of the correction mechanism according to the first embodiment of the present invention. FIG. 8 is a perspective view of a correction mechanism according to a second embodiment of the present invention. FIG. 9 is an exploded perspective view of a correction mechanism according to a second embodiment of the present invention.

Claims (15)

A calibration mechanism for a force / torque sensor includes: a base for fixing a force / torque sensor; and a jig for combining the force / torque sensor to make the force / torque sensor The device is clamped and fixed between the base and the jig; an axial force applying unit having a motor and a load element, the load element is combined with the motor; and a link group having a pivot connection Seat, a linkage lever and a positioning seat, the pivot joint seat is coupled to the jig, the positioning seat is coupled to the load cell, a first end portion of the linkage lever is pivotally connected to the pivot seat, and the A second end is coupled to the positioning base, and the motor drives the jig by the load cell, the positioning base, the linkage rod and the pivot base, and is clamped and fixed to the base and the jig. Force is applied between the force / torque sensors to obtain a force data of the force / torque sensor and a force data of the load cell. The correction mechanism of the force / torque sensor according to item 1 of the patent application scope, further comprising a first carrier and a first sliding group, the first sliding group having a first track and a first sliding group. A first sliding seat is movably disposed on the first track, a base of the first carrier is combined with the first sliding seat of the first sliding group, and a carrier plate of the first carrier is located on the motor Between the load element and the load element, the motor and the load element are respectively coupled to the carrier plate, and the first carrier moves with an axial force direction of the motor. According to the correction mechanism of the force / torque sensor according to item 2 of the patent application scope, wherein the first track is parallel to the axial force applying direction of the motor. The correction mechanism of the force / torque sensor according to item 2 of the patent application scope, further comprising a second carrier, the second carrier having a first bearing portion and a second bearing portion, the first bearing portion The first track of the sliding group is disposed on the first bearing portion, and the motor is disposed on the second bearing portion. The correction mechanism of the force / torque sensor according to item 1 of the patent application scope, wherein The first end portion of the linkage lever is provided with a pivot joint, and the pivot joint is movably pivotally coupled to the pivot joint seat. According to the correction mechanism of the force / torque sensor according to item 5 of the patent application scope, wherein the pivot joint is selected from a cross joint, a ball joint, and a universal joint. The correction mechanism for a force / torque sensor according to item 1 of the scope of the patent application, wherein the positioning base has a receiving groove and positioning plates respectively located on two sides of the receiving groove, and each of the positioning plates has at least one A screw hole, the second end portion of the link rod is disposed in the accommodation slot, and at least one bolt is engaged with the screw hole and abuts the second end portion of the link rod. According to the correction mechanism of the force / torque sensor according to item 7 of the scope of the patent application, wherein the receiving groove has a height, the second end portion of the linkage rod has a thickness, and the height is greater than the thickness. According to the correction mechanism of the force / torque sensor according to item 1, 2, or 7, in the patent application scope, wherein the positioning base has a receiving groove and an adjusting hole penetrating the positioning base, the adjusting hole communicates with the capacity A fixing member is inserted into the adjusting hole through the accommodating groove, the positioning seat is fixed to the load cell, and the second end portion of the linkage rod is disposed in the accommodating groove. According to the correction mechanism of the force / torque sensor according to item 9 of the patent application scope, wherein the adjusting hole has an aperture, the fixing member has an outer diameter, and the adjusting hole has an aperture larger than the outer diameter of the fixing member. . The correction mechanism of the force / torque sensor according to item 4 of the patent application scope, further comprising an adjustment carrier, and the first bearing portion of the second carrier is located in the first sliding group and the adjustment carrier. And the adjustment carrier is coupled to the first bearing part, and the adjustment carrier is used to adjust the second carrier to move in the axial force direction perpendicular to the motor. The correction mechanism of the force / torque sensor according to item 4 of the scope of patent application, further comprising a second sliding group, the second sliding group having a second track and a second slide seat, the second slide Block work The second slide base is arranged on the second track, and the second slide seat is used for setting a measuring tool to measure the linkage rod. According to the correction mechanism of the force / torque sensor according to item 12 of the patent application scope, wherein the second track is parallel to the axial force application direction of the motor. According to the correction mechanism of the force / torque sensor according to item 2 of the scope of patent application, wherein the base has a bearing surface, the axial force direction of the motor is parallel to the bearing surface, and the force / torque sensing The device is fixed on the bearing surface. According to the correction mechanism of the force / torque sensor according to item 2 of the scope of patent application, wherein the base has a bearing surface, the axial direction of the motor is perpendicular to the bearing surface, and the force / torque sensing The device is fixed on the bearing surface.