Torquemeter

Abstract

To provide a structure of a torquemeter allowing flexible setting of sensitivity of torque measurement.SOLUTION: A torquemeter includes a first disk part 2, a second disk part 3, a cylindrical part 1 for connecting the first disk part 2 and the second disk part 3, and a strain detection block 4. A first rotating shaft 51 is connected to the first disk part 2, and a second rotating shaft 52 is connected to the second disk part 3. A first stationary portion 41 being one end of the strain detection block 4 is fixed to a center of the first disk part 2, and a second stationary portion 43 being the other end of the strain detection block 4 is fixed between a connecting portion of the cylindrical part 1 and a connecting portion of the first rotating shaft 51 when viewed in a radial direction. The first stationary portion 41 and the second stationary portion 43 are connected to each other by a strain-inducing portion 42 that is not in contact with the first disk portion 2. The strain-inducing portion 42 has low rigidity, and a strain gauge 7 is fixed to the strain-inducing portion 42.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a technique for measuring torque transmitted by a rotating shaft. [Background technology]

[0002] As a technique for measuring torque transmitted by a rotating shaft, a technique for measuring torque using a torque meter 900 shown in FIG. 10a is known (for example, Patent Document 1). FIG. 10a is a side view of the torque meter 900 with a part cut away, and the hatched part represents the cross section after cutting away. As shown in the figure, this torque meter 900 has a drive-side flange 902 at one axial end of a hollow cylindrical body 901, and a load-side flange 903 at the other end. The central portion of the axial direction of the hollow body 901 is thin-walled, and a strain gauge 904 is fixed to the thin-walled portion of the inner peripheral surface of the hollow body 901 so as to detect shear strain.

[0003] As shown in FIG. 10b, a flange 911 of a drive-side rotating shaft 910 is fastened to a drive-side flange portion 902 of the torque meter 900 with bolts, and a flange 921 of a load-side rotating shaft 920 is fastened to a load-side flange portion 903 with bolts. In such a torque meter 900, a twist corresponding to the torque transmitted between the drive-side rotating shaft 910 and the load-side rotating shaft 920 appears in the thin-walled portion of the hollow body 901, and a shear strain corresponding to this twist appears on the strain gauge 904. Therefore, using such a torque meter 900, the torque transmitted between the drive-side rotating shaft 910 and the load-side rotating shaft 920 is measured from the shear strain detected by the strain gauge 904. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-321335 Summary of the Invention [Problem to be solved by the invention]

[0005] 10a and 10b, the torque measurement sensitivity is determined largely depending on the shape and rigidity of the hollow body 901. For this reason, it may be difficult to achieve both the required shape and rigidity of the hollow body 901 and the required torque measurement sensitivity. Therefore, an object of the present invention is to provide a torque meter structure that allows more flexible setting of torque measurement sensitivity. [Means for solving the problem]

[0006] To achieve the above object, the present invention provides a torque meter for detecting torque, which includes a strain detection block including a torque transmission block for transmitting torque between a first region and a second region, a first fixing portion, a second fixing portion spaced from the first fixing portion, and a connecting member connecting the first fixing portion and the second fixing portion. The first fixing portion of the strain detection block is fixed to the torque transmission block at a first fixing position, which is located toward the second region as viewed from the first region, and the second fixing portion is fixed to the torque transmission block at a second fixing position, which is located toward the first region as viewed from the second region and toward the first region as viewed from the first fixing position. The connecting member has a strain-flexing portion to which a strain gauge for detecting a predetermined strain is fixed, and the strain-flexing portion has low rigidity so as to make it difficult for the strain detected by the strain gauge to occur. The torque meter is also characterized in that the connecting member is constrained to the torque transmission block only via the first fixing portion and the second fixing portion.

[0007] To achieve the above object, the present invention provides a torque meter for detecting torque, comprising: a disk-shaped torque transmission disk for transmitting torque between a first rotating shaft and a second rotating shaft; and a strain detection block. The torque transmission disk transmits torque directly or indirectly to the first rotating shaft within a first annular region; and transmits torque directly or indirectly to the second rotating shaft within a second annular or circular region located more inward than the first region. The strain detection block also comprises a first fixing portion, a second fixing portion spaced apart from the first fixing portion, and a connecting member connecting the first fixing portion and the second fixing portion. The first fixing portion of the strain detection block is fixed to the torque transmission disk at a first fixing position that is located more outward than the second region, and the second fixing portion is fixed to the torque transmission disk at a second fixing position that is located more inward than the first region and the first fixing position. The connecting member has a strain-flexible portion to which a strain gauge for detecting a predetermined strain is fixed, and the strain-flexible portion has low rigidity that makes it difficult for the strain detected by the strain gauge to occur. The connecting member is constrained to the torque transmission disk only via the first fixing portion and the second fixing portion.

[0008] Here, in this torque meter, the strain-flexing part may have a shape that is thin in the tangential or circumferential direction of a circle that passes through the strain-flexing part and is concentric with the torque transmission disk, and the strain gauge may be fixed to a surface that intersects with the thickness direction. Furthermore, in this torque meter, the connecting member may be divided in the direction in which the connecting member extends between the first fixed portion and the second fixed portion, and may have the strain-generating portion and a high-rigidity portion that is at least more rigid than the strain-generating portion and makes it less likely to generate strain that is detected by the strain gauge.

[0009] In this case, the direction in which the strain-flexing portion extends along the connecting member may be set as the axial direction of the torque transmission disk. The present invention also provides a torque meter for detecting torque, comprising a first disk connected to a first rotating shaft, a second disk connected to a second rotating shaft, a columnar portion coaxially connecting the first and second disks, and a strain detection block. The strain detection block comprises a first fixing portion, a second fixing portion spaced apart from the first fixing portion, and a connecting member connecting the first fixing portion to the second fixing portion. The first fixing portion of the strain detection block is fixed to the columnar portion at a first fixing position on the outer circumferential surface of the columnar portion, and the second fixing portion is fixed to the columnar portion at a second fixing position on the outer circumferential surface of the columnar portion spaced apart from the first fixing position in the axial direction of the columnar portion. The connecting member has a strain-flexible portion to which a strain gauge for detecting a predetermined strain is fixed, and the strain-flexible portion has low rigidity so as to make it difficult for the strain gauge to generate strain. The connecting member is constrained to the columnar portion only via the first fixing portion and the second fixing portion.

[0010] To achieve the above object, the present invention provides a torque meter for detecting torque, comprising: a first disk portion connected to a first rotating shaft; a second disk portion connected to a second rotating shaft; a column portion coaxially connecting the first disk portion and the second disk portion; and a strain detection block. The strain detection block comprises a first fixed portion, a second fixed portion spaced apart from the first fixed portion, and a connecting member connecting the first fixed portion and the second fixed portion. The connecting member is configured to span between the first disk portion and the second disk portion in the axial direction of the column portion, the first fixed portion being fixed to the first disk portion, and the second fixed portion being fixed to the second disk portion. The connecting member also has a strain-flexible portion to which a strain gauge for detecting a predetermined strain is fixed, and the strain-flexible portion has low rigidity that makes it difficult for the strain to be detected by the strain gauge to occur.

[0011] Here, in the torque meter having the above-mentioned cylindrical portion, the strain-flexing portion may have a shape that is thin in the tangential or circumferential direction of a circle that passes through the strain-flexing portion and is concentric with the cylindrical portion, and the strain gauge may be fixed to a surface that intersects with the thickness direction. Furthermore, in the torque meter having the above-described cylindrical portion, the connecting member may be divided in the direction in which the connecting member extends between the first fixed portion and the second fixed portion, and may have the strain-generating portion and a high-rigidity portion that is more rigid than the strain-generating portion and makes it less likely to generate strain that is detected by the strain gauge.

[0012] Furthermore, in the torque meter having the above-mentioned cylindrical portion, the direction in which the connecting member extends between the first fixed portion and the second fixed portion in the strain-flexing portion is the radial direction of the cylindrical portion. According to the torque meter described above, the sensitivity of the strain gauge to torque can be changed simply by changing the shape and arrangement of the strain detection block, so that the sensitivity of torque measurement can be set more flexibly. [Effects of the Invention]

[0013] As described above, according to the present invention, it is possible to provide a torque meter structure that allows more flexible setting of torque measurement sensitivity. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a diagram showing the configuration of a torque meter according to a first embodiment of the present invention. FIG. [Figure 2] 2 is a diagram showing the configuration and arrangement of a distortion detection block according to the first embodiment of the present invention. FIG. [Figure 3] 5A and 5B are diagrams illustrating another example of the configuration and arrangement of the distortion detection block according to the first embodiment of the present invention. [Figure 4] 5A and 5B are diagrams illustrating another example of the configuration and arrangement of the distortion detection block according to the first embodiment of the present invention. [Figure 5] 5A and 5B are diagrams illustrating another example of the configuration and arrangement of the distortion detection block according to the first embodiment of the present invention. [Figure 6] FIG. 4 is a diagram showing the configuration of a torque meter according to a second embodiment of the present invention. [Figure 7] FIG. 10 is a diagram showing the configuration of a torque meter according to a third embodiment of the present invention. [Figure 8]FIG. 10 is a diagram showing the configuration of a torque meter according to a fourth embodiment of the present invention. [Figure 9] FIG. 10 is a diagram showing the configuration of a torque meter according to a fourth embodiment of the present invention. [Figure 10] FIG. 1 shows a known torque meter. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of the present invention will be described. First, the first embodiment will be described. FIG. 1a1 shows a perspective view of the torque meter according to the first embodiment, FIG. 1a2 shows a front view of the torque meter, FIG. 1a3 shows a side view of the torque meter, and FIG. 1a4 shows a rear view of the torque meter. As shown in each figure, the torque meter includes a cylindrical columnar portion 1, a disk-shaped first disk portion 2 connected to the front side of the cylindrical portion 1 and coaxial with the cylindrical portion 1, and a disk-shaped second disk portion 3 connected to the back side of the cylindrical portion 1 and coaxial with the cylindrical portion 1. However, the cylindrical portion 1 may also be a hollow cylindrical portion, and in this case, the second disk portion 3 may be a hollow disk provided as a flange of the hollow cylindrical portion.

[0016] A strain detection block 4 is fixed to the front surface of the first disk portion 2. The first disk portion 2 has eight screw holes arranged in an annular area on the outer periphery, and the second disk portion 3 has eight screw holes arranged in an annular area on the outer periphery. Next, as shown schematically in the oblique view of Figure 1b1 and the side view of Figure 1b2, a first flange at the end of the first rotating shaft 51 is connected to the front of the first disc portion 2 using eight bolts and eight screw holes in the first disc portion 2, and a second flange at the end of the second rotating shaft 52 is connected to the back of the second disc portion 3 using eight bolts and eight screw holes in the second disc portion 3.

[0017] Here, as shown in the cross-sectional view of Figure 1c, the first rotating shaft 51 has a hollow cylindrical shape that does not interfere with the strain detection block 4 on the front side of the first disk portion 2 when connected to the first disk portion 2. However, as shown in the cross-sectional view of Figure 1d, the first rotating shaft 51 may be connected to the first disk portion 2 via an adapter 6 that allows the first rotating shaft 51 to be connected to the first disk portion 2 without interfering with the strain detection block 4. Next, the configuration of the distortion detection block 4 is shown in FIG. 2a. The axial direction of the first disk portion 2 is the AX direction, the tangential direction at the position of the strain detection block 4, which is a circle concentric with the first disk portion 2, is the TL direction, and the radial direction of the first disk portion 2 at the position of the strain detection block 4 is the RD direction. Figure 2a1 shows the shape of the strain detection block 4 as seen in the AX direction, Figure 2a2 shows the shape of the strain detection block 4 as seen in the TL direction, and Figure 2a3 shows the shape of the strain detection block 4 viewed obliquely.

[0018] As shown in the figure, the strain detection block 4 is divided into a first fixed portion 41, a strain-generating portion 42, and a second fixed portion 43 in the RD direction. The shaft connecting region is the annular region on the outer periphery of the first disk portion 2 where the screw holes to which the first rotating shaft 51 is connected are arranged, and the central region to which the cylindrical portion 1 is connected, which is annular if the cylindrical portion 1 is hollow or circular if the cylindrical portion 1 is not hollow, is called the cylindrical portion connecting region. As shown in Figure 2b, the first fixing portion 41 is fixed at a central position on the front of the first disk portion 2, and the second fixing portion 43 is fixed at a position on the front of the first disk portion 2, outer periphery of the first fixing portion 41, between the cylindrical portion connecting region and the shaft connecting region. The strain-flexing part 42 has a thin shape in the TL direction and low rigidity so that it can be easily bent and deformed around the axis in the AX direction. However, the strain-flexing part 42 may also have a thin shape that is thin in the circumferential direction at the position of the strain detection block 4, which is concentric with the first disk part 2, and has low rigidity in that circumferential direction.

[0019] Each portion other than the strain-flexing portion 42 is thicker in the TL direction than the strain-flexing portion 42. Furthermore, the portions are not thin in any of the TL, RD, and AX directions, and have high rigidity in each direction. Furthermore, strain gauges 7 are fixed to two surfaces of the strain-flexing part 42 that are perpendicular to the TL direction so as to detect surface bending strain in the RD direction, which is bending in the direction of the arrow in FIG. 2a1. In the torque meter described above, the first disk portion 2 relays the torque transmitted between the first rotating shaft 51 and the second rotating shaft 52 between the inside of the shaft connecting region and the inside of the cylindrical portion connecting region. The first disk portion 2 is deformed in a manner that the shaft connecting region is displaced in the circumferential direction relative to the cylindrical portion connecting region, with a magnitude corresponding to the magnitude of the torque being relayed.

[0020] Furthermore, due to this deformation, second fixed portion 43 is displaced in the circumferential direction relative to first fixed portion 41, causing bending deformation of strain-flexing portion 42 around the axis in the AX direction with a magnitude corresponding to the magnitude of this displacement, and the deformation of strain gauge 7 due to the bending deformation appears as a change in the resistance value of strain gauge 7. Therefore, using such a torque meter, it is possible to measure the torque transmitted between first rotating shaft 51 and second rotating shaft 52 from the change in the resistance value of strain gauge 7.

[0021] The magnitude of the relative circumferential displacement of the second fixed portion 43 with respect to the first fixed portion 41 and the magnitude of the accompanying bending deformation of the strain-flexing portion 42 vary depending on the radial distance between the first fixed portion 41 and the second fixed portion 43. Furthermore, the deformation of the first disk portion 2 becomes greater toward the outer periphery between the shaft connecting region and the columnar portion connecting region.

[0022] Therefore, according to the first embodiment, by using the first disk portion 2 of the same specification and varying the length of the strain-flexing portion 42 of the strain detection block 4, different torque measurement sensitivities can be set. The first embodiment of the present invention has been described above. In the first embodiment, the shape and arrangement of the distortion detection block 4 may be as shown in FIGS. 3a and 3b. Here, Figure 3a1 shows the shape of the distortion detection block 4 when viewed in the AX direction, Figure 3a2 shows the shape of the distortion detection block 4 when viewed in the TL direction, and Figure 3a3 shows the shape of the distortion detection block 4 when viewed obliquely. As shown in the figure, the strain detection block 4 shown in FIG. 3a is the strain detection block 4 shown in FIG. 2a, in which the length in the RD direction of the strain-flexing part 42 is shortened. As shown in Figure 3b, the first fixed portion 41 of the strain detection block 4 is fixed to a position between the cylindrical portion connecting region and the shaft connecting region on the front side of the first disk portion 2, and the second fixed portion 43 is fixed to a position on the front side of the first disk portion 2 that is outer than the first fixed portion 41 and inner than the shaft connecting region. Here, the strain-flexing part 42 has a shape that is recessed in the direction opposite to the first disk part 2 relative to the first fixing part 41 and the second fixing part 43 so as not to come into contact with the first disk part 2. Here, the magnitude of the relative circumferential displacement of the second fixed portion 43 with respect to the first fixed portion 41 and the magnitude of the accompanying bending deformation of the strain-flexing portion 42 vary depending on the radial distance between the first fixed portion 41 and the second fixed portion 43. Furthermore, the deformation of the first disk portion 2 becomes larger toward the outer periphery between the shaft connecting region and the columnar portion connecting region.

[0023] Therefore, according to the strain detection block 4 of Figure 3a, while using the first disk portion 2 of the same specifications, different torque measurement sensitivities can be set by changing the length of the strain-flexing portion 42 and the arrangement of the strain detection block 4. When a hollow cylindrical portion is used as the columnar portion 1 and the shape and arrangement of the strain detection block 4 shown in Figures 3a and 3b are used, the first disk portion 2 may be a hollow disk provided as a flange of the hollow cylindrical portion, as shown in Figure 3c. Alternatively, in the first embodiment described above, the shape and arrangement of the distortion detection block 4 may be as shown in FIGS. 4a and 4b. Here, Figure 4a1 shows the shape of the distortion detection block 4 when viewed in the AX direction, Figure 4a2 shows the shape of the distortion detection block 4 when viewed in the TL direction, and Figure 4a3 shows the shape of the distortion detection block 4 when viewed obliquely. As shown in the figure, the strain detection block 4 is divided into a first fixed portion 411, a high-rigidity portion 412, a strain-generating portion 413, and a second fixed portion 414 in the RD direction. The strain-flexing part 413 has a low rigidity shape with a thin thickness in the TL direction, and strain gauges 7 are fixed to each of the two surfaces perpendicular to the TL direction so as to detect surface bending strain in the RD direction, which bends in the direction of the arrow in Figure 4a1. Each portion other than strain-flexing portion 413 is thicker in the TL direction than strain-flexing portion 413. Furthermore, each portion is not thin in any of the TL, RD, and AX directions, and has high rigidity in each direction. As shown in Figure 4b, the first fixing portion 411 is fixed at a central position on the front of the first disk portion 2, and the second fixing portion 414 is fixed at a position on the outer periphery of the first fixing portion 411 between the cylindrical portion connecting region and the shaft connecting region on the front of the first disk portion 2. Here, the strain-flexing portion 413 and the high-rigidity portion 412 have a shape that is recessed in the direction opposite to the first disk portion 2 more than the first fixing portion 411 and the second fixing portion 414 so as not to come into contact with the first disk portion 2. According to the strain detection block 4 in Figure 4a, the magnitude of the relative circumferential displacement of the second fixed portion 414 with respect to the first fixed portion 411 increases as the combined radial length of the strain-flexing portion 413 and the high-rigidity portion 412 increases, while the bending deformation caused by this displacement occurs concentratedly in the strain-flexing portion 413.

[0024] Therefore, with this strain detection block 4, it is possible to improve the sensitivity of torque measurement compared to when the entire portion between the first fixed portion 411 and the second fixed portion 414 is made of a low-rigidity strain-generating portion. In addition, the sensitivity of torque measurement can also be set by varying the ratio of the lengths of the strain-generating portion 413 and the high-rigidity portion 412. Alternatively, in the first embodiment described above, the shape and arrangement of the distortion detection block 4 may be as shown in FIGS. 5a and 5b. Here, Figure 5a1 shows the shape of the strain detection block 4 as viewed in the AX direction from the first disk portion 2 side, Figure 5a2 shows the shape of the strain detection block 4 as viewed in the TL direction, Figure 5a3 shows the shape of the strain detection block 4 as viewed from the opposite side to Figure 5a1, Figure 5a4 shows the shape of the strain detection block 4 as viewed in the RD direction from the center side of the first disk portion 2, and Figure 5a5 shows the oblique shape of the strain detection block 4.

[0025] As shown in the figure, this strain detection block 4 has a first fixed portion 511 and a second fixed portion 515, and the area between the first fixed portion 511 and the second fixed portion 515 is divided into a first high rigidity portion 512, a strain-generating portion 513, and a second high rigidity portion 514. As shown in Figure 5b, the first fixed portion 511 is fixed at a central position on the front of the first disk portion 2, and the second fixed portion 515 is fixed at a position on the outer periphery of the first fixed portion 511 between the cylindrical portion connecting region and the shaft connecting region on the front of the first disk portion 2. 5a, the AX direction from the back surface to the front surface of the first disk portion 2 is defined as the +AX direction, and the RD direction from the center of the first disk portion 2 to the outer periphery is defined as the +RD direction. The first high rigidity portion 512 is connected to the +RD direction side of the first fixed portion 511, and the second high rigidity portion 514 is connected to the -RD direction side of the second fixed portion 515. The -RD direction end of the second high rigidity portion 514 is located on the +AX direction side of the +RD direction end of the first high rigidity portion 512, and the shapes of each portion are set so that both ends overlap when viewed in the AX direction. The strain-flexing portion 513 is disposed between the -RD direction end of the second high rigidity portion 514 and the +RD direction end of the first high rigidity portion 512, with both ends in the AX direction connected to both ends.

[0026] The strain-flexing part 513 has a thin, low-rigidity shape in the TL direction, and strain gauges 7 are fixed to each of the two surfaces perpendicular to the TL direction so as to detect surface bending strain in the AX direction, which bends in the direction of the arrow in Figure 5a4. Each portion other than strain-flexing portion 513 is thicker in the TL direction than strain-flexing portion 513. Furthermore, each portion is not thin in any of the TL, RD, and AX directions, and has high rigidity in each direction. According to the strain detection block 4 of Figure 5a, similar to the strain detection block 4 of Figure 4a, the sensitivity of torque measurement can be improved compared to when the entire area between the first fixed portion 41 and the second fixed portion 43 is made into a low-rigidity strain-generating portion. The second embodiment will be described below. FIG. 6a1 shows an oblique view of the torque meter according to the second embodiment, FIG. 6a2 shows a front view of the torque meter, FIG. 6a3 shows a side view of the torque meter, FIG. 6a4 shows a rear view of the torque meter, and FIG. 6a5 shows a cross section along the cross section line AA in FIG. 6a4. As shown in the drawings, the torque meter according to the second embodiment does not have the cylindrical portion 1 and the second disk portion 3 of the torque meter of the first embodiment, and as shown in Figures 6b1 and 6b2, a screw hole for connecting the second rotating shaft 52 to the back surface of the first disk portion 2 is provided in the first disk portion 2. In addition, a strain detection block 4 is disposed in a recess provided in the center of the front surface of the first disk portion 2. 6 shows a case where the distortion detection block 4 in FIG. 2 is used, the distortion detection block 4 and its arrangement may be the same as those shown in FIGS. Next, a third embodiment will be described. As shown in a side view of the torque meter in FIG. 7a, in the third embodiment, the strain detection block 4 in the first embodiment is not provided on the first disk portion 2, but instead is fixed to the outer peripheral surface of the cylindrical portion 1. The shape of the strain detection block 4 in Figure 7a is obtained by replacing Figure 2a and the above-mentioned description of the shape of the strain detection block 4 in Figure 2a with the RD direction being the axial direction of the cylindrical portion 1, the AX direction being the radial direction of the cylindrical portion 1, and the TL direction being the tangential direction at the position of the strain detection block 4, which is a circle concentric with the cylindrical portion 1.

[0027] In the third embodiment, the first fixing portion 41 and the second fixing portion 43 are fixed to the outer peripheral surface of the columnar portion 1 at positions spaced apart in the axial direction of the columnar portion 1 . In the torque meter described above, the cylindrical portion 1 relays torque transmitted between the first rotating shaft 51 and the second rotating shaft 52 via the first disk portion 2 and the second disk portion 3. A torsional deformation of the cylindrical portion 1 occurs at a magnitude corresponding to the magnitude of the torque being relayed, causing the first fixed portion 41 to be displaced in the circumferential direction of the cylindrical portion 1 relative to the second fixed portion 43, which changes the resistance value of the strain gauge 7 as described above. Therefore, using such a torque meter, the torque transmitted between the first rotating shaft 51 and the second rotating shaft 52 can be measured from the change in the resistance value of the strain gauge 7.

[0028] Furthermore, as in the first embodiment, by using a cylindrical portion 1 of the same specifications while varying the length of the strain-generating portion 42 of the strain detection block 4 or the arrangement of the strain detection block 4, different torque measurement sensitivities can be set. Although Figure 7a shows the case where a distortion detection block 4 having the shape shown in Figure 2a is used, distortion detection blocks 4 having the shapes shown in Figures 4a and 5a may also be used as the distortion detection block 4, as shown in Figures 7b and 7c. The shape of the strain detection block 4 in these cases can also be obtained by replacing the RD direction with the axial direction of the cylindrical portion 1, the AX direction with the radial direction of the cylindrical portion 1, and the TL direction with the tangential direction at the position of the strain detection block 4 on a circle concentric with the cylindrical portion 1 in Figures 4a and 5a and the above-mentioned description of the shape of the strain detection block 4. Furthermore, by replacing it with the strain detection block 4 in Figures 4a and 5a, the same effect as the effect of the strain detection block 4 in Figures 4a and 5a can be obtained.

[0029] Next, a fourth embodiment will be described. As shown in the perspective view of the torque meter in FIG. 8a, in the fourth embodiment, the strain detection block 4 in the first embodiment is not provided on the first disk portion 2, but instead the strain detection block 4 is fixed so as to bridge between the first disk portion 2 and the second disk portion 3. The shape of the strain detection block 4 in Figure 8a is obtained by replacing Figure 2a and the above-mentioned description of the shape of the strain detection block 4 in Figure 2a with the RD direction being the axial direction of the first disk portion 2 and the second disk portion 3, the AX direction being the radial direction of the first disk portion 2 and the second disk portion 3, and the TL direction being the tangential direction at the position of the strain detection block 4, which is a circle concentric with the first disk portion 2 and the second disk portion 3.

[0030] In the fourth embodiment, the first fixing portion 41 of the strain detection block 4 is fixed to the outer peripheral surface of the second disk portion 3, and the second fixing portion 43 is fixed to the back surface of the first disk portion 2. However, if the diameters of the first disk portion 2 and the second disk portion 3 are the same, the first fixing portion 41 of the strain detection block 4 may be fixed to the front surface of the second disk portion 3, and the second fixing portion 43 may be fixed to the back surface of the first disk portion 2. Alternatively, if the diameters are the same, the first fixing portion 41 of the strain detection block 4 may be fixed to the outer peripheral surface of the second disk portion 3, and the second fixing portion 43 may be fixed to the outer peripheral surface of the first disk portion 2.

[0031] In the torque meter described above, the first fixed portion 41 is displaced in the circumferential direction of the cylindrical portion 1 relative to the second fixed portion 43 due to the torsional deformation of the first disk portion 2, the cylindrical portion 1, and the second disk portion 3 as a whole, which occurs at a magnitude corresponding to the magnitude of the torque between the first rotating shaft 51 and the second rotating shaft 52, which is relayed by the entire first disk portion 2, the cylindrical portion 1, and the second disk portion 3.

[0032] This displacement changes the resistance value of strain gauge 7 as described above. Therefore, using such a torque meter, the torque transmitted between first rotating shaft 51 and second rotating shaft 52 can be measured from the change in the resistance value of strain gauge 7. Furthermore, as in the first embodiment, by using the first disk portion 2, the cylindrical portion 1, and the second disk portion 3 of the same specifications, and varying the length of the strain-generating portion 42 and the arrangement of the strain detection block 4, different torque measurement sensitivities can be set. Although Figure 8a shows the case where the distortion detection block 4 having the shape shown in Figure 2a is used, the distortion detection block 4 may also have the shape shown in Figure 4a, as shown in Figure 8b. The shape of the strain detection block 4 in this case is the same as that in Figure 4a and the above-mentioned description of the shape of the strain detection block 4 in Figure 4a, with the RD direction being interpreted as the axial direction of the first disk portion 2 and the second disk portion 3, the AX direction being interpreted as the radial direction of the first disk portion 2 and the second disk portion 3, and the TL direction being interpreted as the tangential direction at the position of the strain detection block 4 on a circle concentric with the first disk portion 2 and the second disk portion 3.

[0033] In addition, as the strain detection block 4 in the fourth embodiment, a strain detection block 4 may be used in which both ends are fixed to the outer peripheral surface of the first disk portion 2 and the outer peripheral surface of the second disk portion 3, as shown in the perspective view of the torque meter in Figure 9a. 9b is a perspective view of the strain detection block 4, and FIG. 9c shows the shape of the strain detection block 4 as viewed in the axial direction from the first disk portion 2 to the second disk portion 3. As shown in FIG. As shown in the figure, this strain detection block 4 has a first fixed portion 711 fixed to the outer peripheral surface of the first disk portion 2 and a second fixed portion 715 fixed to the outer peripheral surface of the second disk portion 3, and the area between the first fixed portion 711 and the second fixed portion 715 is divided into a first high rigidity portion 712, a strain-generating portion 713, and a second high rigidity portion 714.

[0034] A first high rigidity portion 712 is connected to the back side of the first fixed portion 711 so as to extend the first fixed portion 711 in the direction of the second disk portion 3, and a second high rigidity portion 714 is connected to the front side of the second fixed portion 715 so as to extend the second fixed portion 715 in the direction of the first disk portion 2. The ends of the first high rigidity portion 712 and the second high rigidity portion 714 overlap when viewed in the radial direction of the first disk portion 2 and the second disk portion 3, and a strain-flexing portion 713 is arranged with both ends connected in the radial direction to both ends.

[0035] In addition, the strain-flexing portion 713 has a low-rigidity shape with a thin thickness in the tangential direction of a circle concentric with the first disk portion 2 and the second disk portion 3 that passes through the strain-flexing portion 713, and strain gauges 7 are fixed to each of the two surfaces perpendicular to the tangential direction so as to detect radial surface bending strain of the first disk portion 2 and the second disk portion 3, which bend in the direction of the arrow in Figure 9c.

[0036] Each part other than strain-flexing part 713 is thicker in the tangential direction than strain-flexing part 513, and is not thin at all but has high rigidity in each direction. [Explanation of symbols]

[0037] 1... cylindrical portion, 2... first disk portion, 3... second disk portion, 4... strain detection block, 6... adapter, 7... strain gauge, 41... first fixed portion, 42... strain-generating portion, 43... second fixed portion, 51... first rotating shaft, 52... second rotating shaft, 411... first fixed portion, 412... high-rigidity portion, 413... strain-generating portion, 414... second fixed portion, 511... first fixed portion, 512... first high-rigidity portion, 51 3...strain-flexing portion, 514...second high-rigidity portion, 515...second fixed portion, 711...first fixed portion, 712...first high-rigidity portion, 713...strain-flexing portion, 714...second high-rigidity portion, 715...second fixed portion, 900...torque meter, 901...hollow body portion, 902...drive side flange portion, 903...load side flange portion, 910...rotating shaft, 911...flange, 920...rotating shaft, 921...flange.

Claims

1. A torque meter for detecting torque, a torque transmission block that transmits torque between the first region and the second region; a strain detection block including a first fixed portion, a second fixed portion spaced apart from the first fixed portion, and a connecting member connecting the first fixed portion and the second fixed portion; the first fixing portion of the strain detection block is fixed to the torque transmission block at a first fixing position, which is a position in a direction toward the second region as viewed from the first region, and the second fixing portion is fixed to the torque transmission block at a second fixing position, which is a position in a direction toward the first region as viewed from the second region and is a position in a direction toward the first region as viewed from the first fixing position, the connecting member has a strain-flexing portion to which a strain gauge for detecting a predetermined strain is fixed, and the strain-flexing portion has low rigidity that makes it difficult for the strain to be detected by the strain gauge to occur; The torque meter according to claim 1, wherein the connecting member is constrained to the torque transmission block only via the first fixing portion and the second fixing portion.

2. A torque meter for detecting torque, a torque transmission disk that transmits torque between the first rotating shaft and the second rotating shaft; a strain detection block; the torque transmission disk transmits torque directly or indirectly to the first rotating shaft within a first annular region, and transmits torque directly or indirectly to the second rotating shaft within a second annular or circular region located on the inner circumferential side of the first region, the strain detection block includes a first fixed portion, a second fixed portion spaced apart from the first fixed portion, and a connecting member connecting the first fixed portion and the second fixed portion, the first fixing portion of the strain detection block is fixed to the torque transmission disk at a first fixing position that is a position on the outer circumferential side of the second region, and the second fixing portion is fixed to the torque transmission disk at a second fixing position that is a position on the inner circumferential side of the first region and the first fixing position, the connecting member has a strain-flexing portion to which a strain gauge for detecting a predetermined strain is fixed, and the strain-flexing portion has low rigidity that makes it difficult for the strain to be detected by the strain gauge to occur; The torque meter is characterized in that the connecting member is constrained to the torque transmission disk only via the first fixing portion and the second fixing portion.

3. 3. The torque meter according to claim 2, The strain-flexing portion has a shape that is thin in the tangential or circumferential direction of a circle that passes through the strain-flexing portion and is concentric with the torque transmission disk, and the strain gauge is fixed to a surface that intersects with the thickness direction.

4. 4. The torque meter according to claim 2 or 3, a torque meter characterized in that the connecting member is divided in a direction in which the connecting member extends between the first fixed portion and the second fixed portion, and has the strain-flexible portion and a high-rigidity portion that is at least more rigid than the strain-flexible portion and makes it less likely to generate strain that is detected by the strain gauge.

5. 5. The torque meter according to claim 4, A torque meter characterized in that the direction in which the strain-flexing part extends along the connecting member is the axial direction of the torque transmission disk.

6. A torque meter for detecting torque, a first disk portion connected to the first rotary shaft; a second disk portion connected to the second rotating shaft; a columnar portion coaxially connecting the first disk portion and the second disk portion; a strain detection block; the strain detection block includes a first fixed portion, a second fixed portion spaced apart from the first fixed portion, and a connecting member connecting the first fixed portion and the second fixed portion, the first fixing portion of the strain detection block is fixed to the cylindrical portion at a first fixing position on an outer peripheral surface of the cylindrical portion, and the second fixing portion is fixed to the cylindrical portion at a second fixing position on the outer peripheral surface of the cylindrical portion that is spaced apart from the first fixing position in an axial direction of the cylindrical portion, the connecting member has a strain-flexing portion to which a strain gauge for detecting a predetermined strain is fixed, and the strain-flexing portion has low rigidity that makes it difficult for the strain to be detected by the strain gauge to occur; The torque meter according to claim 1, wherein the connecting member is constrained to the cylindrical portion only via the first fixing portion and the second fixing portion.

7. A torque meter for detecting torque, a first disk portion connected to the first rotary shaft; a second disk portion connected to the second rotating shaft; a columnar portion coaxially connecting the first disk portion and the second disk portion; a strain detection block; the strain detection block includes a first fixed portion, a second fixed portion spaced apart from the first fixed portion, and a connecting member connecting the first fixed portion and the second fixed portion, the connecting member is bridged between the first disk portion and the second disk portion in the axial direction of the columnar portion, the first fixing portion is fixed to the first disk portion, and the second fixing portion is fixed to the second disk portion, The torque meter is characterized in that the connecting member has a strain-flexible portion to which a strain gauge for detecting a predetermined strain is fixed, and the strain-flexible portion has low rigidity that makes it difficult for the strain detected by the strain gauge to occur.

8. 8. The torque meter according to claim 6 or 7, The strain-flexing portion has a shape that is thin in the tangential or circumferential direction of a circle that passes through the strain-flexing portion, which is concentric with the cylindrical portion, and the strain gauge is fixed to a surface that intersects with the thickness direction.

9. 8. The torque meter according to claim 6 or 7, a torque meter characterized in that the connecting member is divided in a direction in which the connecting member extends between the first fixed portion and the second fixed portion, and has the strain-flexible portion and a high-rigidity portion that is more rigid than the strain-flexible portion and makes it less likely to generate strain that is detected by the strain gauge.

10. 8. The torque meter according to claim 6 or 7, A torque meter characterized in that the direction in which the connecting member extends between the first fixed portion and the second fixed portion at the strain-flexing portion is a radial direction of the cylindrical portion.

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