JP2015087180A - Rotation transmission apparatus with torque measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a whirling amount of a first encoder 10 to a second encoder 11 which results in measurement errors low with a structure that can increase resolution of torque measurement.SOLUTION: A fitting cylindrical part 66 of a core metal 35 constituting the first encoder 10 is fitted to a small diameter part 71 provided on the other end part of a connection shaft 9. A slide bearing 70 is provided between a large diameter part 69 provided on an inner peripheral surface in the other end part of an output shaft 14b and an outer peripheral surface of the fitting cylindrical part 66.

Description

  The present invention relates to an improvement in a rotation transmission device with a torque measuring device that is incorporated in, for example, an automatic transmission for automobiles, transmits torque by a rotating shaft, and is used for measuring torque transmitted by the rotating shaft.

  The rotational speed of the rotary shaft constituting the automatic transmission for automobiles and the torque transmitted by the rotary shaft are measured, and the measurement results are used as information for performing shift control of the transmission or engine output control. It has been used for a long time. On the other hand, as a device that can be used for measuring the torque, the amount of elastic torsional deformation of the rotating shaft transmitting torque is converted into a phase difference between the output signals of a pair of sensors. An apparatus for measuring the torque based on the above is known (for example, see Patent Document 1). Such a conventional structure will be briefly described below with reference to FIG.

  In the case of the first example of the conventional structure shown in FIG. 6, a pair of encoders 2 and 2 are externally fixed at two positions in the axial direction of the target rotating shaft 1. The magnetic characteristics of the outer peripheral surfaces of the encoders 2 and 2 that are the detected portions change alternately and at equal pitches in the circumferential direction. In addition, the pitches at which the magnetic properties of the outer peripheral surfaces change in the circumferential direction are equal to each other on the outer peripheral surfaces. In addition, the sensors 3 and 3 are supported by a housing (not shown) in a state where the detection portions of the pair of sensors 3 and 3 are opposed to both the outer peripheral surfaces. These sensors 3 and 3 change their output signals in response to changes in the magnetic characteristics of the portions where their detection portions are opposed to each other.

  The output signals of the sensors 3 and 3 as described above periodically change as the encoders 2 and 2 rotate together with the rotating shaft 1. The frequency (and period) of this change takes a value commensurate with the rotational speed of the rotary shaft 1. For this reason, this rotational speed is calculated | required based on this frequency (or period). When the rotary shaft 1 is elastically twisted and deformed as torque is transmitted by the rotary shaft 1, the encoders 2 and 2 are relatively displaced in the rotational direction. As a result, the phase difference ratio (= phase difference / 1 period) between the output signals of the sensors 3, 3 changes. The phase difference ratio takes a value commensurate with the torque (elastic torsional deformation amount of the rotating shaft 1). Therefore, the torque can be obtained based on this phase difference ratio.

  However, when the first example of the conventional structure as described above is incorporated and used in an automatic transmission for automobiles, the torsional rigidity of the rotating shaft 1 to be measured is high. There is a problem that it is difficult to secure a sufficient amount of torsional deformation and the resolution of torque measurement is lowered. In addition, since the two sensors 3 and 3 that are separated from each other in the axial direction are used, there is a problem that it is difficult to dispose the two harnesses 4 and 4 drawn from both the sensors 3 and 3. In addition, since it is necessary to provide support and fixing portions for each of the sensors 3 and 3 in the housing in a highly accurate relative positional relationship, there is a problem that the processing of the housing becomes difficult.

  On the other hand, in Patent Document 1, as shown in FIG. 7, the detected portions of a pair of encoders 2a and 2a fixed at two positions in the axial direction of the rotating shaft 1 are extended toward the central portion in the axial direction. In addition, there is described a structure in which the detection portions of a pair of sensors constituting one sensor unit 5 arranged in the central portion in the axial direction are opposed to the detection portions of the encoders 2a and 2a. However, also in the case of this second example of the conventional structure, when it is incorporated in an automatic transmission for an automobile, the torsional rigidity of the target rotating shaft 1 is high, so that the torsional deformation of the rotating shaft 1 is elastic. It is difficult to secure a sufficient amount. Therefore, even with the above-described second example of the conventional structure, the problem that the resolution of torque measurement is low cannot be solved.

  In Patent Document 2, a pair of rotating shafts each having an encoder fixed to each outer peripheral surface are arranged on the same straight line, and the ends of both rotating shafts are more elastic than the two rotating shafts. A structure in which both ends of a torsion bar that easily twists and deforms is connected is described. In the case of the third example of the conventional structure described in Patent Document 2, the relative displacement amount in the rotational direction of both encoders can be increased based on the elastic torsional deformation of the torsion bar that occurs during torque transmission. . For this reason, the resolution of torque measurement can be improved accordingly. However, when the third example of such a conventional structure is applied to a counter shaft of an automobile automatic transmission, it is difficult to sufficiently improve the resolution of torque measurement. That is, the input gear and the output gear are fixed at two positions in the axial direction of the counter shaft, and the portion of the counter shaft that is elastically torsionally deformed when torque is transmitted is between the two gears. Only the part between. For this reason, when the third example of the conventional structure as described above is applied to such a countershaft, the torsion bar needs to be installed between the two gears. Therefore, the axial dimension of the torsion bar is equal to or smaller than the axial distance between the two gears. However, in the case of the countershaft, since the axial distance between these two gears is narrow, the axial dimension of the torsion bar cannot be made sufficiently long. Therefore, it is not possible to secure a sufficient amount of elastic torsional deformation of the torsion bar that occurs when torque is transmitted. As a result, it is difficult to sufficiently improve the resolution of torque measurement.

[First example of structure according to undisclosed prior invention]
8-17 has shown the 1st example (Japanese Patent Application No. 2013-132497, Japanese Patent Application No. 2013-183072) of the rotation transmission apparatus with a torque measuring device considered previously in view of the above situations. The rotation transmission device with a torque measuring device according to the present invention is equipped with a so-called transverse engine (transverse engine) such as a front-wheel drive vehicle or a four-wheel drive vehicle employing a prime mover and a transmission arrangement similar to the front-wheel drive vehicle. Incorporated into the counter shaft and counter gear portion of the automatic transmission for automobiles. A first example of such a rotation transmission device with a torque measuring device according to the prior invention includes a housing (mission case) not shown, a rotary shaft unit 6 functioning as a counter shaft, and each functioning as a counter gear. An input gear 7 as a gear and an output gear 8 as a second gear, a connecting shaft 9, a first encoder 10, a second encoder 11, and one sensor unit 12 are provided. Since FIG. 14 is a simplified diagram of FIG. 13, illustration of some parts and parts and entry of symbols are omitted.

  The rotating shaft unit 6 includes an input shaft 13 that is a hollow first rotating shaft, an output shaft 14 that is a hollow second rotating shaft, and a hollow torsion bar 15. Of these, the input shaft 13 and the output shaft 14 are each made of an alloy steel such as carbon steel in a cylindrical shape, arranged concentrically with each other, and combined with each other so as to be relatively rotatable. Yes. In addition, in this specification and a claim, with respect to each of the input shaft 13 (first rotation shaft) and the output shaft 14 (second rotation shaft), one end portion refers to an end portion on the side close to each other. The other end portion is an end portion on a side far from each other.

  In the case of the illustrated structure, in order to combine the one end portions of the input shaft 13 and the output shaft 14 so as to be relatively rotatable, an input side combination cylinder portion 16 is provided at one end portion of the input shaft 13, An output side combination cylinder portion 17 having a diameter larger than that of the input side combination cylinder portion 16 is provided at one end portion of the output shaft 14. The input side combination cylinder part 16 is inserted into the inner diameter side of the output side combination cylinder part 17. In this state, a radial needle bearing 18 is installed between the cylindrical peripheral surfaces of the combination cylinder portions 16 and 17 facing each other. Along with this, between the step surface 19 provided at the base end portion of the outer peripheral surface of the input side combination tube portion 16 and the distal end surface 20 of the output side combination tube portion 17 facing the step surface 19, An annular thrust washer 21 that is a thrust sliding bearing is sandwiched. Further, by adopting such a configuration, the one end portions of the input shaft 13 and the output shaft 14 are combined in a state in which relative displacement is possible and displacement in a direction approaching each other in the axial direction is prevented. ing.

  Further, as shown in detail in FIG. 16 (A), the thrust washer 21 is provided with slits 22 and 22 that are long in the radial direction at a plurality of circumferentially equal intervals in the annular body portion. It forms in the state opened to the inner periphery. At the same time, a reinforcing cylindrical portion 23 bent at a right angle in the axial direction from the outer peripheral edge is provided around the entire outer periphery of the main body portion. The reinforcing cylindrical portion 23 of the thrust washer 21 has a base end portion of the input side combination cylindrical portion 16 in a state in which the distal end edge of the reinforcing cylindrical portion 23 faces the other end side of the input shaft 13. In addition, it is externally fitted without large backlash in the radial direction. At the same time, the radial intermediate portion of the main body portion of the thrust washer 21 is sandwiched between the step surface 19 and the tip surface 20. Further, in this state, each of the slits 22 and 22 includes the radial needle bearing 18 which is a pair of spaces existing at positions sandwiching the portion between the step surface 19 and the tip surface 20 from both radial sides. The installed annular space and the space existing on the outer diameter side of the output side combination cylinder portion 17 are communicated with each other. That is, in order to realize such a communication state, the diameter of the inscribed circle of each of the slits 22 and 22 (inner diameter of the main body portion) is made smaller than the diameter of the inner peripheral edge of the tip surface 20, and The diameter of the circumscribed circle of the slits 22 and 22 is made larger than the diameter of the outer peripheral edge of the distal end surface 20.

  The torsion bar 15 is made of a steel material having a sufficient spring property and is formed into a hollow circular tube. The input shaft 13 and the output shaft are arranged on the inner diameter side of the input shaft 13 and the output shaft 14. 14 and the concentricity. In this state, the torsion bar 15 has one end (the right end in FIGS. 12 to 14) on the input shaft 13 and the other end (the left end in FIGS. 12 to 14) on the output shaft 14. They are connected so that they cannot rotate relative to each other. In order to realize such a connected state, in the case of the structure shown in the drawing, the outer diameter of the torsion bar 15 is slightly increased at both ends compared to the middle portion, and the outer peripheral surfaces of these both end portions are increased. These are engaged with a portion near the other end of the inner peripheral surface of the input shaft 13 and a portion near the other end of the inner peripheral surface of the output shaft 14 in a relatively non-rotatable manner. Specifically, these both engaging portions are involute spline engaging portions 24a and 24b (engaging portions formed by engaging both male and female involute spline portions without rattling in the circumferential direction). That is, the first male involute spline portion 50 provided on the outer peripheral surface of the one end portion of the torsion bar 15 is rattled in the circumferential direction on the first female involute spline portion 51 provided on the inner peripheral surface of the other half portion of the input shaft 13. The involute spline engaging part 24a is configured by engaging without any problem. At the same time, a second male involute spline portion 52 provided on the outer peripheral surface of the other end portion of the torsion bar 15 is connected to a second female involute spline portion 53 provided on the inner peripheral surface of the other end portion of the output shaft 14 in the circumferential direction. The involute spline engaging portion 24b is configured by engaging without rattling. Note that an engaging portion having another rotation preventing structure such as a key engaging portion can be adopted as both engaging portions. In this state, the torsion bar 15 is clamped from both sides in the axial direction by a pair of retaining rings 25a and 25b locked to the inner peripheral surfaces of the input shaft 13 and the output shaft 14. The axial displacement of the input shaft 13 and the output shaft 14 is prevented.

  In the case of the structure shown in the figure, the portion sandwiched between the involute spline engaging portions 24a and 24b in the axially intermediate portion of the torsion bar 15 is elastically twisted when torque is transmitted. The spring portion 65 is deformed. And the axial direction dimension L of this spring part 65 is made larger than the axial direction space | interval W of the input gear 7 and the output gear 8 which are described below (L> W). In the example shown in the drawing, L is set to a size slightly larger than four times W (L> 4W).

  The input gear 7 is a helical gear made of alloy steel such as carbon steel, and is externally fixed to the intermediate portion of the input shaft 13. The fitting portion between the inner peripheral surface of the input gear 7 and the outer peripheral surface of the input shaft 13 is a cylindrical surface fitting portion 26a for ensuring concentricity (both outer diameter side and inner diameter side cylindrical surfaces are press-fitted together. And the involute spline engaging portion 24c for preventing relative rotation are disposed adjacent to each other in the axial direction. Further, the positioning of the input gear 7 in the axial direction with respect to the input shaft 13 is performed on one side surface of the input gear 7 (FIG. 8, FIG. 8) on a stepped surface 27 formed near the one end of the intermediate portion of the outer peripheral surface of the input shaft 13. This is achieved by bringing the inner peripheral portion of the left side surfaces of 9, 12, and 13) into contact with each other. In addition, a parking lock gear 28 is formed integrally with the inner peripheral portion of one side surface of the input gear 7. At the time of parking lock, the rotation shaft unit 6 cannot be rotated by engaging a tip portion of a lock member (not shown) with a part of the outer peripheral surface of the parking lock gear 28 in the circumferential direction. The output gear 8 is a helical gear made of alloy steel such as carbon steel, and is formed (fixed) integrally with the output shaft 14 at a portion near one end of the intermediate portion of the outer peripheral surface of the output shaft 14. ing. In the case of the illustrated structure, the torque input from the input gear 7 to the input shaft 13 during the forward rotation of the rotating shaft unit 6 (when the automobile is moving forward) is To the output shaft 14 and output from the output gear 8. At this time, the spring portion 65 of the torsion bar 15 is elastically twisted and deformed by an amount corresponding to the magnitude of the torque.

  The rotary shaft unit 6 is rotatably supported with respect to the housing by a pair of tapered roller bearings 29a and 29b arranged so that their contact angles are opposite to each other. In the case of the illustrated structure, in order to assemble these tapered roller bearings 29a and 29b to the rotary shaft unit 6, an inner ring 30a constituting one tapered roller bearing 29a is disposed at a portion near the other end of the input shaft 13. It is fitted. At the same time, a spacer 31 is sandwiched between the large-diameter side end surface of the inner ring 30 a and the other side surface of the input gear 7. In this state, the inner ring 30a is pressed against the input shaft 13 by pressing the small-diameter side end surface of the inner ring 30a with a nut 32a that is screwed into the other end portion of the outer peripheral surface of the input shaft 13 and further tightened. 30a and the input gear 7 are coupled and fixed. Further, the inner ring 30b constituting the other tapered roller bearing 29b is externally fitted to the portion near the other end of the output shaft 14, and the large-diameter side end surface of the inner ring 30b is connected to the outer peripheral surface of the output shaft 14. It is made to contact | abut on the level | step difference surface 33 formed in the edge side part. In this state, the inner ring 30b is attached to the output shaft 14 by pressing the end surface on the small diameter side of the inner ring 30b with a nut 32b that is screwed into the other end portion of the outer peripheral surface of the output shaft 14 and further tightened. The support is fixed.

  Further, in the case of the structure shown in the drawing, the inclination directions of the teeth of the input gear 7 and the output gear 8, each of which is a helical gear, are determined when the gears 7 and 8 are rotated forward (the rotary shaft unit 6 Are controlled such that the axial reaction forces acting on both gears 7 and 8 are in a direction facing each other (pressing each other). Thereby, at the time of forward rotation of the two gears 7 and 8, at least a part of the axial reaction force acting on the two gears 7 and 8 can be canceled. As a result, the axial load applied to the tapered roller bearings 29a and 29b during the forward rotation of the gears 7 and 8 is suppressed, and the friction loss (dynamic torque) of the bearings 29a and 29b is correspondingly reduced. I try to suppress it.

  The connecting shaft 9 is arranged on the inner diameter side of the torsion bar 15 concentrically with the torsion bar 15. At the same time, the connecting shaft 9 has one end portion (the right end portion in FIGS. 13 and 14) connected to the input shaft 13 in a relatively non-rotatable manner and the other end portion (the left end portion in FIGS. 13 and 14). The torsion bar 15 and the other end opening of the output shaft 14 are projected. In the case of the illustrated structure, one end of the connecting shaft 9 protrudes from one end opening of the torsion bar 15 in order to connect the one end of the connecting shaft 9 to the input shaft 13 in such a manner that it cannot rotate relative to the input shaft 13. At the same time, an outward flange-shaped flange 34 is formed on the outer peripheral surface of the protruding portion. And the outer peripheral surface of this collar part 34 and the other end part inner peripheral surface of the said input shaft 13 are engaged so that relative rotation is impossible. Specifically, this engaging portion is an involute spline engaging portion 24d. In addition, as this engagement part, the engagement part with another rotation prevention structure, such as a key engagement part, can also be employ | adopted. Further, in this state, the connecting shaft 9 is held by holding the flange 34 from both sides in the axial direction by the retaining ring 25a and another retaining ring 25c that are engaged with the inner peripheral surface of the input shaft 13. The axial displacement of is prevented. The two involute spline engaging portions 24a and 24d existing at one end portion of the torsion bar 15 and one end portion of the connecting shaft 9 are the first female involute spline portions as the respective female involute spline portions. 51 is shared.

  The first encoder 10 is fitted and fixed to the other end of the connecting shaft 9 concentrically with the connecting shaft 9. In other words, the first encoder 10 is supported and fixed to the input shaft 13 via the connecting shaft 9. For this reason, the first encoder 10 can rotate (synchronously) with the input shaft 13. The second encoder 11 is externally fitted and fixed to the other end of the output shaft 14 concentrically with the output shaft 14. Therefore, the second encoder 11 can rotate (synchronously) with the output shaft 14.

  Further, the first and second encoders 10 and 11 are each made of a magnetic metal and made of an annular cored bar 35 that is externally fitted and fixed to the other end of the connecting shaft 9 or the other end of the output shaft 14. (36) and a cylindrical permanent magnet 37 (38) fixed to the outer peripheral surface of the cylindrical portion existing on the outer peripheral portion of the core bar 35 (36). The outer peripheral surface of the permanent magnet 37 constituting the first encoder 10 is defined as a first detected portion 39, and the outer peripheral surface of the permanent magnet 38 constituting the second encoder 11 is defined as a second detected portion 40. It is said. These first and second detected parts 39 and 40 are equal in diameter, are concentric with each other, and are adjacent to each other in the axial direction (for example, within an interval of 10 mm or less, preferably 5 mm or less in the axial direction). Open). The detected portions 39 and 40 have S poles and N poles arranged alternately and at equal pitches in the circumferential direction. The total number of magnetic poles (S poles and N poles) of these detected parts 39 and 40 coincides with each other.

  In the case of the structure shown in the figure, the fitting portion between the inner peripheral surface of the metal core 35 constituting the first encoder 10 and the outer peripheral surface of the other end of the connecting shaft 9 is a cylinder for ensuring concentricity. The surface fitting part 26b and the involute spline engaging part 24e for preventing relative rotation are adjacently arranged in the axial direction. Further, the core bar 35 is prevented from coming off from the connecting shaft 9 by a retaining ring 25d locked to the outer peripheral surface of the other end portion of the connecting shaft 9. The core bar 36 constituting the second encoder 11 is externally fixed to the other end portion of the output shaft 14 by an interference fit.

  The sensor unit 12 includes a holder 41 made of synthetic resin, and first and second sensors 42 a and 42 b embedded in the tip of the holder 41. Magnetic detection elements such as a Hall element, a Hall IC, an MR element, and a GMR element are incorporated in the detection units of both the sensors 42a and 42b. In such a sensor unit 12, the detection part of the first sensor 42a is in close proximity to the first detected part 39 and the detection part of the second sensor 42b is in close proximity to the second detected part 40. And supported by the housing.

  In the case of the illustrated structure, an oil introduction path 43 that opens only at one end surface of the connecting shaft 9 is provided at the radial center of the connecting shaft 9. The lubricating oil introduced into the oil introduction passage 43 is supplied into the tapered roller bearings 29a and 29b through the end opening of the oil introduction passage 43. For this purpose, oil passages 44a and 44b are provided in the portions near both ends of the connecting shaft 9, the torsion bar 15, and the input shaft 13 and the output shaft 14, respectively. And by these both oil paths 44a and 44b, the minute annular space which exists in the inner diameter side of the small diameter side edge part of the inner ring | wheels 30a and 30b of the both tapered roller bearings 29a and 29b of the both ends of the said oil introduction path 43, and the tapered roller bearings 29a and 29b. 45a and 45b are communicated. Further, oil grooves 46a and 46b extending in the radial direction are formed in one or a plurality of circumferential directions on the front end surfaces of the nuts 32a and 32b. As a result, the lubricating oil introduced into the oil introduction passage 43 from the end opening of the oil introduction passage 43 is transferred to the oil passages 44a and 44b, the annular spaces 45a and 45b, and the oil grooves 46a and 46b. And is supplied to the inside of the both tapered roller bearings 29a and 29b.

  Further, in the case of the structure shown in the figure, a part of the lubricating oil fed into the both oil passages 44a and 44b is present in the both involute spline engaging portions 24a and 24b from the intermediate portion between the both oil passages 44a and 44b. Through the gap, the air is fed into a cylindrical space 47 that exists between the outer peripheral surface of the spring portion 65 of the torsion bar 15 and the inner peripheral surface of the intermediate portion of the input shaft 13 and the output shaft 14. And the stepped surface which exists in the base end part of the front end surface 48 of the said input side combination cylinder part 16, and the inner peripheral surface of the said output side combination cylinder part 17 the lubricating oil sent in this cylindrical space 47 49 is supplied to the installation portion of the radial needle bearing 18 and the clamping portion of the thrust washer 21 through a gap existing between them, and the installation portion and the clamping portion are lubricated. At this time, the lubricating oil that has reached the clamping portion passes smoothly through the plurality of slits 22 and 22 provided in the thrust washer 21 while being used for lubrication of the clamping portion. As a result, the lubricating oil is efficiently supplied to and discharged from the installation portion of the radial needle bearing 18 and the clamping portion of the thrust washer 21, and the lubrication state of the installation portion and the clamping portion is improved.

  In the case of carrying out the first example of the structure according to the previous invention, instead of the thrust washer 21 as shown in FIG. 16A, the outer peripheral portion as shown in FIG. The thrust washer 21a in which the reinforcing cylindrical portion is omitted, or a simple annular thrust washer 21b in which the outer peripheral reinforcing cylindrical portion and the plurality of slits are omitted as shown in FIG. You can also. However, it is preferable to use the thrust washers 21 and 21a with the slits 22 and 22 shown in (A) and (B) from the viewpoint of improving the lubrication state of the installation part and the clamping part. Furthermore, from the viewpoint of securing the strength of the outer peripheral portion (particularly the vicinity of the base end portion of each of the slits 22 and 22), it is preferable to use the thrust washer 21 with the reinforcing cylindrical portion 23 shown in (A).

  Further, in the case of the structure shown in the drawing, the lubricating oil fed into the both oil passages 44a and 44b passes from the intermediate portion between the two oil passages 44a and 44b to the inner peripheral surface of the torsion bar 15 and the outer peripheral surface of the connecting shaft 9. Are also fed into a minute gap (cylindrical gap having a radial thickness of about 0.2 mm). Particularly, in the case of the illustrated structure, in order to smoothly feed the lubricating oil into such a minute gap, both the oil passages 44a in the axial direction of the outer peripheral surface of the connecting shaft 9 are provided. , 44b are provided with grooves 54a, 54b extending around the entire circumference. During operation, the lubricating oil filled in the minute gap exhibits a function as a film damper that attenuates minute vibrations of the connecting shaft 9.

  In the case of the first example of the rotation transmission device with a torque measuring device according to the previous invention configured as described above, the output signals of the first and second sensors 42a and 42b constituting the sensor unit 12 are the rotation shaft unit. 6 (the input shaft 13 and the output shaft 14) and the first and second encoders 10 and 11 rotate, respectively, and periodically change. Here, the frequency (and period) of this change takes a value commensurate with the rotational speed of the rotary shaft unit 6. Therefore, if the relationship between these frequencies (or periods) and the rotational speed is examined in advance, the rotational speed can be obtained based on the frequencies (or periods). Further, when torque is transmitted between the input gear 7 and the output gear 8 by the rotary shaft unit 6, the spring portion 65 of the torsion bar 15 is elastically twisted and deformed. Both the gears 7 and 8 (the shafts 13 and 14 and the encoders 10 and 11) are relatively displaced in the rotation direction. As a result of the relative displacement of the encoders 10 and 11 in the rotational direction in this way, the phase difference ratio (= phase difference / 1 period) between the output signals of the first and second sensors 42a and 42b. Change. Here, this phase difference ratio takes a value commensurate with the torque. Therefore, if the relationship between the phase difference ratio and the torque is examined in advance, the torque can be obtained based on the phase difference ratio.

  In particular, in the case of the first example of the structure according to the present invention, the torsion bar 15 is disposed on the inner diameter side of the input shaft 13 and the output shaft 14 and the axial dimension L of the spring portion 65 of the torsion bar 15 is set. Is larger than the axial interval W between the gears 7 and 8 (L> W). Therefore, it is possible to sufficiently secure the elastic torsional deformation amount of the spring portion 65 that is generated when torque is transmitted. As a result, unlike the structure in which the rotary shaft unit 6 is an integral rotary shaft, both the gears 7 and 8 that are generated when the torque is transmitted, regardless of the axial distance W between the gears 7 and 8. The relative displacement in the rotational direction between them can be made sufficiently large. Therefore, the resolution of torque measurement can be sufficiently increased. In the case of the first example of the structure according to the present invention, the material of the torsion bar 15, the axial dimension, the outer diameter dimension, the radial thickness, etc. of the spring portion 65 are adjusted at the design stage. Thus, the torsional rigidity of the spring portion 65 can be easily adjusted. For this reason, the relationship (gain) between the torque and the relative displacement amount in the rotational direction can be easily designed to a desired value as compared with a structure in which the rotational shaft unit 6 is an integral rotational shaft.

  Further, in the case of the first example of the structure according to the previous invention, since only one sensor unit 12 is used, the number of harnesses (not shown) drawn from the sensor unit 12 can be reduced to one. Easy to arrange. Further, since the sensor unit 12 provided on the housing has only one supporting and fixing portion, the processing of the housing can be facilitated.

FIG. 18 shows a modification of the first example of the structure according to the above-described invention. In the case of the first example of the structure according to the above-described invention, the first and second encoders 10 and 11 and the sensor unit 12 are concentrated around the other end of the output shaft 14. In the case of this modification, both the first and second encoders 10 and 11 and the sensor unit 12 are concentrated around the other end portion of the input shaft 13. For this reason, in the case of this modification, the outer peripheral surface of one end portion (left end portion in FIG. 18) of the connecting shaft 9 arranged on the inner diameter side of the torsion bar 15 is connected to the inner peripheral surface of the other end portion of the output shaft 14. In this case, they are connected so as not to rotate relative to each other by key engagement or the like. Along with this, a retaining ring (not shown) is used to prevent the connecting shaft 9 from being displaced in the axial direction with respect to the output shaft 14. In this state, the other end portion (the right end portion in FIG. 18) of the connecting shaft 9 is projected from the other end opening of the input shaft 13. The first encoder 10 is fitted and fixed to the other end of the connecting shaft 9, and the second encoder 11 is fixed to the other end of the input shaft 13. Further, the sensor unit 12 is supported by a housing (not shown) in a state where the detection parts of the pair of sensors constituting the sensor unit 12 are opposed to the detection parts of the first and second encoders 10 and 11. doing.
18 is a simplified diagram similar to FIG. 14, illustration of some parts and parts and entry of reference numerals are omitted, but other configurations and operations are the structures according to the above-described prior invention. This is the same as the case of the first example.

  In the case of the first example (and its modification) of the structure according to the above-described invention, the input side rotating body 55 which is the first rotating body composed of the input shaft 13 and the input gear 7, Torque transmission between the output shaft 14 and the output-side rotating body 56, which is the second rotating body composed of the output gear 8, is always performed only through the torsion bar 15 regardless of the magnitude of the torque. The structure to do is adopted. For this reason, the spring portion 65 of the torsion bar 15 is twisted so as not to cause plastic deformation even when the torque transmitted between the input side and output side rotating bodies 55 and 56 is maximized. It is necessary to have rigidity.

  On the other hand, in the case of the first example (and its modification) of the structure according to the above-described invention, the lower the torsional rigidity of the spring portion 65 of the torsion bar 15, that is, the elasticity of the spring portion 65 is. As the amount of torsional deformation increases, the resolution of torque measurement can be increased. However, as described above, in the case of the first example (and its modification) of the structure according to the previous invention, the rigidity of the spring part 65 is limited only to the extent that the spring part 65 is not plastically deformed when the maximum torque is transmitted. Cannot be reduced (torque measurement resolution cannot be increased).

[Second example of structure according to undisclosed prior invention]
19-22 has shown the 2nd example (Japanese Patent Application No. 2013-183072) of the rotation transmission apparatus with a torque measuring device which considered previously in view of the above situations. The feature of the second example of the structure according to the prior invention is that a structure for further improving the resolution of torque measurement is added to the first example of the structure according to the previous invention shown in FIGS. It is in the point. The structure and operation of the other parts are the same as in the case of the first example of the structure according to the previous invention, except for a part. Therefore, overlapping illustrations and explanations are omitted or simplified. The description will focus on the characteristic part of the second example of the structure and the part different from the first example of the structure according to the above-described invention.

  First, in the case of the second example of the structure according to the previous invention, a radial bearing and a thrust bearing installed at a combination portion of one end portions of the input shaft 13 and the output shaft 14a constituting the rotating shaft unit 6a are provided. This is different from the case of the first example of the structure according to the previous invention. That is, in the case of the second example of the structure according to the previous invention, the radial bearing is a cylindrical sleeve bearing 57 which is a radial sliding bearing, and the thrust bearing is an annular ring which is a thrust sliding bearing. The thrust washer 21c is used. Of these, the thrust washer 21c is positioned in the radial direction by being externally fitted to the proximal end portion of the input side combination cylinder portion 16 without large backlash. At the same time, the thrust washer 21c is positioned in the circumferential direction by engaging a pin 58 implanted in the stepped surface 19 with an engagement hole 59 provided in a part of the thrust washer 21c. . In the case of the second example of the structure according to the present invention, an oil passage 60 penetrating in the radial direction is formed in the proximal end portion of the input side combination cylinder portion 16. Through the oil passage 60, the lubricating oil can be supplied from the cylindrical space 47 to a portion between the space where the sleeve bearing 57 is installed and the space where the thrust washer 21c is installed. As a result, the lubricity in both spaces is improved. In addition, regarding each structure which concerns on a prior invention, the radial bearing and thrust bearing installed in the combination part of the one end parts of the said input shaft 13 and the said output shaft 14 (14a) are respectively a sliding bearing and a rolling bearing. Either may be selected.

  Further, in the case of the second example of the structure according to the above-described invention, an uneven shape in the circumferential direction, which is a first stopper portion, is formed on the inner diameter side portion of the parking lock gear 28 formed integrally with the input gear 7a. An input side stopper portion (female side stopper portion) 61 having an internal gear shape is provided. The input-side stopper portion 61 has a plurality of recesses 62 and 62 that are opened on one end surface (the left end surface in FIGS. 19 and 21) and the inner peripheral surface of the parking lock gear 28, at equal intervals in the circumferential direction. It is provided. Further, an output side stopper portion (male side) having a concave-convex shape (gear shape) in the circumferential direction, which is a second stopper portion, is provided on the outer diameter side portion of one end portion (the right end portion in FIGS. 19 and 21) of the output shaft 14a. (Stopper portion) 63 is provided. The output side stopper portion 63 includes a plurality of convex portions 64 and 64 (the same number as the concave portions 62 and 62) protruding in the axial direction from the outer diameter side portion of the one end surface of the output shaft 14a in the circumferential direction. Provided at equal intervals.

  The input-side stopper portion 61 and the output-side stopper portion 63 are concavo-convexly engaged so as to allow only relative rotation within a predetermined angle range. This predetermined angle range is a range of predetermined angles in both forward and reverse directions with reference to the neutral state in which the torsion bar 15 is not twisted and deformed. That is, the circumferential width of each concave portion 62, 62 constituting the input side stopper portion 61 is made larger than the circumferential width of each convex portion 64, 64 constituting the output side stopper portion 63, and The convex portions 64 and 64 are arranged inside the concave portions 62 and 62 in a state where the phases in the circumferential direction of the concave portions 62 and 62 and the convex portions 64 and 64 in the neutral state coincide with each other. Inserting. That is, these convex portions 64 and 64 are loosely engaged inside the concave portions 62 and 62 with gaps on both sides in the circumferential direction. Thereby, when the relative rotation between the input side stopper portion 61 and the output side stopper portion 63 reaches the upper limit value on the forward rotation side or the reverse rotation side of the predetermined angle range, The convex portions 64 and 64 are engaged with each other so that torque can be transmitted (the circumferential side surfaces of the concave portions 62 and 62 and the convex portions 64 and 64 are in contact with each other). In addition, this allows relative rotation between the input side rotating body 55a composed of the input gear 7a and the input shaft 13 and the output side rotating body 56a composed of the output shaft 14a and the output gear 8 to be within the predetermined angle range. Regulated within. This predetermined angle range is a range in which the torsional deformation of the spring portion 65 provided in the axially intermediate portion of the torsion bar 15 does not lead to plastic deformation.

  In the case of the second example of the rotation transmission device with a torque measuring device according to the previous invention configured as described above, the torque transmitted between the input side and output side rotating bodies 55a, 56a is relatively small, A state in which the amount of torsional deformation (torsion angle) of the spring portion 65 of the torsion bar 15 is relatively small, that is, the amount of torsional deformation is within a predetermined amount within the elastic range of the spring portion 65 (forward rotation side or reverse of the predetermined angle range). In a state where the amount does not reach the upper limit on the rotation side), the concave portions 62 and 62 and the convex portions 64 and 64 do not engage with each other so that torque can be transmitted (the concave portions 62 and 62 and the convex portions). 64, 64 circumferential side surfaces do not contact each other). Therefore, in this state, torque transmission between the input side and output side rotating bodies 55a, 56a is performed only through the torsion bar 15.

  On the other hand, when the torque increases and the amount of torsional deformation of the spring portion 65 reaches the predetermined amount within the elastic range of the spring portion 65, the concave portions 62 and 62 and the convex portions 64 and 64 are connected to each other. Engage so that torque can be transmitted (the circumferential side surfaces of the concave portions 62 and 62 and the convex portions 64 and 64 contact each other). In this state, torque transmission between the input-side and output-side rotating bodies 55a, 56a is not only performed through the torsion bar 15, but also the concave portions 62, 62 and the convex portions 64. , 64 is also performed through the engaging portion. Further, in the state where the concave portions 62 and 62 and the convex portions 64 and 64 are engaged with each other so as to be able to transmit torque, the amount of torsional deformation of the spring portion 65 is further prevented. For this reason, even when a large torque is transmitted, the spring portion 65 can be prevented from being plastically deformed.

  That is, in the case of the second example of the structure according to the present invention, based on the engagement between the input side and output side stoppers 61 and 63, the input side and output side rotating bodies 55a and 56a are connected to each other. Since the relative rotatable range is a range in which plastic deformation does not occur in the spring portion 65, the torsional rigidity of the spring portion 65 can be set to a size that matches the desired resolution of torque measurement. Therefore, for example, when the maximum torque transmitted between the input-side and output-side rotating bodies 55a, 56a is transmitted only through the torsion bar 15, plastic deformation does not occur in the spring portion 65. A smaller torsional rigidity than the minimum torsional rigidity can be set for the spring portion 65. And by performing such a setting, the resolution of torque measurement (at least in the low torque region) until the input side and output side stopper portions 61, 63 are engaged with each other so as to be able to transmit torque, It can be made higher than in the case of the first example of the structure according to the previous invention.

  Although not shown, in the case of the second example of the structure according to the above-described prior invention, as in the case of the first example of the structure according to the above-described prior invention, the first and second modifications A configuration in which the encoders 10 and 11 and the sensor unit 12 are concentrated around the other end of the input shaft 13 (configuration as shown in FIG. 18) can be employed.

  When the prior invention is carried out, the detected portions of the first and second encoders and the sensor unit in the first and second examples (and their modifications) of the structure according to the above-described previous invention It is also possible to adopt a configuration in which the facing direction of the pair of sensors constituting the pair is changed from the radial direction to the axial direction. When implementing such a modified example, the detected parts of both the first and second encoders are a pair of annular-shaped detected parts having different radial dimensions, and both the detected parts are They are arranged concentrically (superimposed in the radial direction) in the same direction with respect to the axial direction. And the detection part of a pair of sensor which comprises a sensor unit is made to oppose these both to-be-detected parts to an axial direction.

  The rotation transmission device with a torque measuring device according to the prior invention as described above, regardless of the axial distance between the input gear 7 (7a) and the output gear 8, these two gears 7 (7a), A sufficient amount of relative displacement in the rotational direction between the eight can be secured to sufficiently increase the resolution of torque measurement, but there is room for further improvement in terms of suppressing torque measurement errors. That is, in the case of each structure according to the previous invention, the outer peripheral surface of the flange portion 34 formed at one end portion of the connecting shaft 9 and the inner peripheral surface of the other end portion of the input shaft 13 are engaged by the involute spline engaging portion 24d. Thus, the connecting shaft 9 is supported with respect to the input shaft 13. Moreover, the intermediate | middle part thru | or other end part of this connection shaft 9 are not supported with respect to fixed parts, such as a casing (the other end part of this connection shaft 9 is a free end). Therefore, the second encoder 11 fitted and fixed to the other end portion of the output shaft 14 of the first encoder 10 fitted and fixed to the other end portion of the connecting shaft 9 is connected to the measurement error of the torque during torque transmission. (There is a misalignment between the rotation centers of the first and second encoders 10, 11).

JP-A-1-254826 Japanese Utility Model Publication No. 217311

  In the structure of the rotation transmission device with a torque measuring device capable of increasing the resolution of torque measurement in view of the above-described circumstances, the present invention causes misalignment between the rotation centers of a pair of encoders, which leads to a measurement error. It was invented to realize a structure that can suppress this.

Each of the rotation transmission devices with a torque measuring device of the present invention includes a housing, a rotary shaft unit, a first gear, a second gear, a connecting shaft, a first encoder, a second encoder, and one sensor. A unit.
Of these, the rotating shaft unit includes both hollow first and second rotating shafts and a hollow torsion bar. Of these, the first and second rotating shafts are arranged concentrically with each other, and are rotatably supported with respect to the housing in a state where their one end portions are combined so as to be relatively rotatable. The torsion bar is disposed on the inner diameter side of the first and second rotary shafts, concentrically with the first and second rotary shafts, and has one end at the first rotary shaft and the other end. The parts are connected to the second rotating shaft so as not to rotate relative to each other.
The first gear is fixed to an intermediate portion in the axial direction of the outer peripheral surface of the first rotating shaft.
The second gear is fixed to an intermediate portion in the axial direction of the outer peripheral surface of the second rotating shaft.
Of the axially intermediate portion of the torsion bar, a portion that elastically twists and deforms when transmitting torque (the torsion bar is connected to the first and second rotating shafts so as not to rotate relative to each other). The axial dimension of the spring portion, which is a portion sandwiched between both ends, is larger than the axial interval between the first and second gears.
Further, the connecting shaft is disposed concentrically with the torsion bar on the inner diameter side of the torsion bar, and has one end portion with respect to any one of the first and second rotating shafts. The other end portion is projected in the axial direction from the end portion of the torsion bar in a state where the relative rotation is impossible.
In addition, the first encoder has a first detected portion that is concentric with the connecting shaft and is annular (for example, cylindrical or annular) in a state of being fixed to the other end of the connecting shaft, The magnetic characteristics of the first detected part are changed alternately and at equal pitches in the circumferential direction.
Further, the second encoder is fixed to the other end portion of the other rotating shaft, and is concentric with the other rotating shaft and is annularly (for example, cylindrical or annular) to be detected. And the magnetic characteristics of the second detected portion are changed alternately and at equal pitches in the circumferential direction.
The first and second detected parts are arranged close to each other (for example, arranged with an interval of within 10 mm, more preferably within 5 mm).
The sensor unit is supported with respect to the housing in a state where a part of the sensor unit is opposed to the first and second detected parts, and the first and second detected parts. Among them, the output signal is changed in response to the change in the magnetic characteristic of the part facing itself. As such a sensor unit, for example, a first sensor opposed to the first detected portion and a second sensor opposed to the second detected portion are provided. However, it is possible to employ one having a configuration in which the output signal is changed in response to the change in the magnetic characteristics of the portion of the first and second detected parts facing each other.

  In the case of the rotation transmission device with a torque measuring device according to claim 1, the other end portion inner peripheral surface of the other rotation shaft and the connection shaft of the core metal constituting the connection shaft or the first encoder. A sliding bearing is provided between the outer peripheral surface of the fitting cylinder portion with respect to the inner surface.

On the other hand, in the case of the rotation transmission device with a torque measuring device according to claim 2, a flange portion is provided on the outer peripheral surface of one end portion of the connecting shaft, and this flange portion is the other end of the one rotation shaft. By press-fitting into the inner peripheral surface of the part, the connecting shaft is supported so as not to rotate relative to the one rotating shaft.
The invention described in claim 1 and the invention described in claim 2 can be carried out simultaneously.

  When the rotation transmission device with a torque measuring device according to the present invention is implemented, for example, as in the second example (or a modification thereof) of the structure according to the previous invention, the first rotating shaft, the first gear, A first stopper portion provided in a part of the first rotating body, and a second stopper portion provided in a part of the second rotating body including the second rotating shaft and the second gear. The first stopper portion and the second stopper portion are configured so that the torque is applied only when the torsional deformation amount (torsion angle) of the spring portion of the torsion bar reaches a predetermined amount within the elastic range of the spring portion. It is also possible to engage so that transmission is possible.

In the case of the rotation transmission device with a torque measuring device of the present invention configured as described above, the resolution of torque measurement can be increased as in the case of each structure according to the previous invention. That is, since the axial dimension of the spring portion of the torsion bar is larger than the axial distance between the first and second gears, the torque is generated when torque is transmitted regardless of the width of the axial distance. The amount of torsional deformation of the spring portion based on the relative displacement in the rotational direction between the first and second gears can be increased. Therefore, the resolution of torque measurement can be increased. In addition, since the first and second detected parts constituting both the first and second encoders are arranged close to each other, the sensor unit facing the first and second detected parts is made one, The number of harnesses drawn from the sensor unit can be reduced to one, and the harness can be easily arranged. Further, since the sensor unit has only one supporting and fixing portion with respect to the housing, the processing of the housing can be facilitated.
In addition, according to the rotation transmission device with a torque measuring device of the present invention, the first and second encoders can have good concentricity between the rotation centers, which leads to a torque measurement error. The amount of swirling with respect to the two encoders can be kept small.

  When the present invention is implemented, if the structure includes both the first and second stopper portions as in the second example of the structure according to the previous invention (or a modification thereof), torque measurement is possible. The resolution can be set to a desired size, and the torsion bar can be prevented from being plastically deformed regardless of the magnitude of the torque transmitted between the first and second gears.

The end view which omits a housing and a sensor unit and shows the 1st example of an embodiment of the invention. FIG. 2 is a cross-sectional view taken along line aa in FIG. 1. The left end enlarged view of FIG. The figure similar to FIG. 2 which shows the 2nd example of embodiment of this invention. The right end part enlarged view of FIG. The schematic side view which shows the 1st example of a conventional structure. The schematic side view which cuts a part and shows the 2nd example. The perspective view which abbreviate | omits a housing and a sensor unit and shows the 1st example of the structure which concerns on a prior invention. Similarly, the side view which abbreviate | omits a housing and shows. The figure which abbreviate | omitted the sensor unit and was seen from the left side of FIG. The figure seen from the right side of FIG. The disassembled perspective view which abbreviate | omits a housing and a sensor unit and shows the 1st example of the structure which concerns on a prior invention. Bb sectional drawing of FIG. FIG. 14 is a simplified diagram of FIG. 13. The c section enlarged view of FIG. The perspective view which shows three examples of the thrust washer applicable to the structure which concerns on a prior invention. The left end part enlarged view of FIG. The simplified view similar to FIG. 14 which shows the modification of the 1st example of the structure which concerns on a prior invention. The perspective view which shows the 2nd example of the structure which concerns on a prior invention in the state before a housing and a sensor unit are abbreviate | omitted and engaging an input side stopper part and an output side stopper part further. The d section enlarged view of FIG. Sectional drawing which abbreviate | omits a housing and shows the 2nd example of the structure which concerns on a prior invention. The e section enlarged view of FIG.

[First example of embodiment]
1 to 3 show a first example of an embodiment of the present invention corresponding to claim 1. The feature of this example is that the first encoder 10 has a good concentricity between the rotation centers of both the first and second encoders 10 and 11, and this leads to a torque measurement error. It has a structure to keep the turning amount small. Regarding the structure and operation of other parts, the first example of the structure according to the prior invention shown in FIGS. 8 to 17 and the second example of the structure according to the prior invention shown in FIGS. Since it is the same as the case, overlapping illustrations and descriptions will be omitted or simplified, and the following description will be focused on the features of this example.

  In the case of this example, the first encoder 10 is fixed to the other end portion of the connecting shaft 9 concentrically with the connecting shaft 9 as in the examples of the structure according to the previous invention. The first encoder 10 includes a magnetic metal cored bar 35 and a permanent magnet 37. Of these, the metal core 35 is a cylindrical fitting tube portion 66 fitted to the other end portion of the connecting shaft 9, and an outward flange shape provided at an intermediate portion in the axial direction of the fitting tube portion 66. The circular ring part 67 and a cylindrical part 68 provided in a direction from the outer peripheral edge of the circular ring part 67 toward the other axial end side of the connecting shaft 9. The permanent magnet 37 is fixed to the outer peripheral surface of the cylindrical portion 68 over the entire circumference.

  In the case of this example, between the large-diameter portion 69 provided on the inner peripheral surface of the other end portion of the output shaft 14b and the outer peripheral surface of one end portion (the right end portion in FIGS. 2 and 3) of the fitting tube portion 66, A sliding bearing 70 made of a slippery material such as oil-impregnated metal or synthetic resin is provided. The slide bearing 70 is assembled as follows. First, the connecting shaft 9 is engaged by engaging the outer peripheral surface of the flange 34 formed at one end of the connecting shaft 9 with the inner peripheral surface of the other end of the input shaft 13 by the involute spline engaging portion 24d. The input shaft 13 is supported. In this state, the flange portion 34 is sandwiched from both sides in the axial direction by a pair of retaining rings 25 a and 25 c locked to the inner peripheral surface of the input shaft 13, and the connecting shaft 9 is connected to the input shaft 13. Prevent axial displacement. Next, the hollow circular torsion bar 15 is inserted into the inner diameter side of the input shaft 13 and the output shaft 14 b from the other end opening of the output shaft 14. Then, by engaging the first male involute spline portion 50 provided on the outer peripheral surface of the one end portion of the torsion bar 15 with the first female involute spline portion 51 provided on the inner peripheral surface of the other half portion of the input shaft 13, The second male involute spline portion 53 provided on the outer peripheral surface of the other end portion of the output shaft 14b is replaced with a second female involute spline portion 53 provided on the outer peripheral surface of the other end portion of the torsion bar 15 as the involute spline engaging portion 24a. By engaging with the involute spline portion 24b. Thus, the torsion bar 15 is supported on the inner diameter side of the input shaft 13 and the output shaft 14b. Next, the sliding bearing 70 is press-fitted into the large-diameter portion 69 of the output shaft 14b, and one side surface (the right side surface in FIG. 2) of the sliding bearing 70 is pressed against the other end surface of the torsion bar 15. As a result, the torsion bar 15 is sandwiched from both sides in the axial direction between the retaining ring 25a and the sliding bearing 70, and the axial displacement of the torsion bar 15 relative to the input shaft 13 and the output shaft 14 is prevented. . Next, the second encoder 11 is concentric with the output shaft 14b with respect to the output shaft 14b by externally fixing and fixing the core bar 36 constituting the second encoder 11 to the other end portion of the output shaft 14b. , And supports synchronous rotation. And the fitting cylinder part 66 of the core metal 35 which comprises said 1st encoder 10 is fitted to the small diameter part 71 provided in the other end part of the said connection shaft 9 (cylindrical surface fitting for ensuring concentricity) The joint portion 26b and an involute engaging portion 24e for preventing relative rotation are configured), and the axial displacement of the core metal 35 is prevented by the retaining ring 25d. Thus, the first encoder 10 is supported and fixed to the input shaft 13 via the connecting shaft 9 so as to be concentric with and synchronized with the input shaft 13, and the fitting cylinder portion. The outer peripheral surface of one end portion (right end portion in FIG. 2) of 66 is slidably contacted or closely opposed to the inner peripheral surface of the sliding bearing.

The procedure for assembling the torque transmission device-equipped rotation transmission device of the present example is not limited to the procedure described above. That is, after supporting the torsion bar 15 on the inner diameter side of the input shaft 13 and the output shaft 14b, the connecting shaft 9 is inserted into the inner diameter side of the torsion bar 15 or the other end of the output shaft 14b. After the sliding bearing 70 is press-fitted into the portion, the flange portion 34 of the connecting shaft 9 is supported in a state in which axial displacement with respect to the input shaft 13 is prevented by a pair of retaining rings 25a and 25c. You can also do things.
Further, the sliding bearing 70 is press-fitted into the outer peripheral surface of one end portion of the fitting tube portion 66 of the core bar 35 constituting the first encoder 10, and the fitting tube portion 66 is inserted into the small diameter portion 71 of the connecting portion 9. By fitting, the outer peripheral surface of the sliding bearing 70 and the large-diameter portion 69 of the output shaft 14b can be brought into sliding contact or close to each other.

  According to the rotation transmission device with the torque measuring device of the present example as described above, the amount of swinging of the first encoder 10 relative to the second encoder 11 that leads to a torque measurement error is reduced while increasing the resolution of torque measurement. It can be suppressed. Increasing the resolution of torque measurement among these can be realized for the same reason as in each of the examples of the structure according to the previous invention. That is, in the case of this example, the torsion bar 15 is arranged on the inner diameter side of the input shaft 13 and the output shaft 14b, so that the axial dimension of the spring portion 65 of the torsion bar 15 is outside the intermediate portion of the input shaft 13. It is larger than the axial interval between the fitted input gear 7 and the output gear 8 provided at the intermediate portion of the output shaft 14b. For this reason, it is possible to sufficiently secure the elastic torsional deformation amount of the spring portion 65 that is generated when torque is transmitted between the input shaft 13 and the output shaft 14b. By measuring with the second encoders 10 and 11, the resolution of torque measurement can be sufficiently increased.

  Further, suppressing the swing amount of the first encoder 10 relative to the second encoder 11 constitutes the first encoder 10 with a large diameter portion 69 provided on the inner peripheral surface of the other end of the output shaft 14b. This can be achieved by providing a slide bearing 70 between the outer peripheral surface of one end of the fitting tube portion 66 of the core metal 35. That is, the inner peripheral surface of the sliding bearing 70 press-fitted into the large-diameter portion 69 is slidably contacted or closely opposed to the outer peripheral surface of the fitting cylinder portion 66 that is externally fitted and fixed to the other end portion of the connecting shaft 9. Therefore, the concentricity between the rotation center of the first encoder 10 supported and fixed to the other end of the connecting shaft 9 and the rotation center of the second encoder 11 supported and fixed to the output shaft 14b can be improved. . As a result, the amount of swinging of the first encoder 10 relative to the second encoder 11 that leads to a torque measurement error can be kept small. Further, since the first and second encoders 10 and 11 are arranged adjacent to each other in the axial direction, only one sensor unit (not shown) is required. Therefore, the number of harnesses drawn from the sensor unit can be reduced to one, and the arrangement of the harnesses can be facilitated.

  Further, in the case of this example, one side surface of the slide bearing 70 press-fitted into the large diameter portion 69 of the output shaft 14 b is pressed against the other end surface of the torsion bar 15. Therefore, as in the examples of the structure according to the previous invention, the torsion bar 15 is clamped from both sides in the axial direction by the retaining rings 25a and 25b that are locked to the inner peripheral surfaces of the input shaft 13 and the output shaft 14 (14a). Compared with the case where it does, it can prevent more effectively that the said torsion bar 15 shakes in an axial direction with respect to the said input shaft 13 and the said output shaft 14b. Further, the output shaft 14b does not need to be provided with a locking groove for locking the retaining ring 25b on the inner peripheral surface of the other end of the output shaft 14b as in the examples of the structure according to the previous invention. Thus, the rotation transmission device with a torque measuring device can be reduced in size and weight.

[Second Example of Embodiment]
4 and 5 show a second example of an embodiment of the present invention corresponding to claim 2. The characteristics of this example also improve the concentricity between the rotation centers of both the first and second encoders 10 and 11 as in the first example of the above-described embodiment, leading to torque measurement errors. The first encoder 10 has a structure for minimizing the swinging amount of the first encoder 10 with respect to the second encoder 11. Regarding the structure and operation of other parts, the first example of the structure according to the prior invention shown in FIGS. 8 to 17 and the second example of the structure according to the prior invention shown in FIGS. Since it is the same as the case, overlapping illustrations and descriptions will be omitted or simplified, and the following description will be focused on the features of this example.

  In the case of this example, an outward flange-shaped flange portion 34a formed on the outer peripheral surface of one end portion of the connecting shaft 9a is press-fitted into the large diameter portion 72 provided on the inner peripheral surface of the other end portion of the input shaft 13a. 9a is supported with respect to the input shaft 13a so as to be concentric with and synchronized with the input shaft 13a. Then, the other side surface (the left side surface in FIGS. 4 and 5) of the flange 34 a is pressed against one end surface (the right end surface in FIGS. 4 and 5) of the torsion bar 15.

According to the rotation transmission device with the torque measuring device of the present example as described above, the amount of swinging of the first encoder 10 relative to the second encoder 11 that leads to a torque measurement error is reduced while increasing the resolution of torque measurement. It can be suppressed. Increasing the resolution of torque measurement among these can be realized for the same reason as in each of the examples of the structure according to the previous invention.
In the case of this example, the connecting shaft 9a is supported to the input shaft 13a by press-fitting the flange 34a of the connecting shaft 9a into the large diameter portion 72 of the input shaft 13a. . Therefore, as in each example of the structure according to the previous invention, the central axis of the connecting shaft 9a is compared with the case where the connecting shaft 9 is supported on the input shaft 13 via the involute spline engaging portion 24a. In addition, the concentricity between the central axis of the input shaft 13a and the central axis of the output shaft 14 can be improved. As a result, the concentricity between the rotation centers of the first and second encoders 10 and 11 can be improved, and the amount of swinging of the first encoder 10 relative to the second encoder 11 is related to torque measurement error. Can be kept small.

  In the case of this example, the other side surface of the flange portion 34 a press-fitted into the large-diameter portion 72 of the input shaft 13 a is pressed against one end surface of the torsion bar 15. For this reason, as in the first example of the structure according to the previous invention, the torsion bar 15 is clamped from both sides in the axial direction by the retaining rings 25a and 25b locked to the inner peripheral surfaces of the input shaft 13 and the output shaft 14. As compared with the above, it is possible to more effectively prevent the torsion bar 15 from rattling in the axial direction with respect to the input shaft 13 a and the output shaft 14. Furthermore, since it is not necessary to provide a locking groove for locking the retaining rings 25a and 25c on the inner peripheral surface of the other end of the input shaft 13a as in the examples of the structure according to the previous invention, the input shaft The axial dimension of the shaft 13a can be shortened, and the rotation transmission device with the torque measuring device can be reduced in size and weight.

When practicing the present invention, the first example and the second example of the above-described embodiment can be carried out simultaneously. That is, a sliding bearing is installed at the other end of the output shaft, and a flange formed at one end of the connecting shaft is press-fitted into the other end of the input shaft. According to the structure in which the first example and the second example of the embodiment are simultaneously performed, the swing amount of the first encoder relative to the second encoder can be further reduced, and the torsion bar can be connected to the input shaft and the second shaft. Shaking in the axial direction of the output shaft can be more effectively prevented.
Each example of the embodiment described above shows an example in which the present invention is applied to the second example of the structure of the prior invention shown in FIGS. 19 to 22 described above, but the present invention is not limited to this. First, the first example of the structure of the prior invention shown in FIGS. 8 to 17 described above, the modification of the first example of the structure of the prior invention as shown in FIG. 18 described above, or the structure according to the previous invention. It can also be applied to a modification of the second example.

The type of transmission used by incorporating the present invention is not particularly limited as long as it has a counter shaft and a counter gear. A dual clutch transmission (DCT), an automatic transmission (AT), a continuously variable transmission ( Various types such as CVT) and manual transmission (MT) can be adopted. Further, the measured rotational speed and torque may be used for vehicle control other than shift control and engine output control. Further, the prime mover placed on the upstream side of the transmission does not necessarily need to be an internal combustion engine such as a gasoline engine or a diesel engine, and may be an electric motor used in a hybrid vehicle or an electric vehicle, for example.
Furthermore, when implementing the present invention, it is essential to measure the torque, but it is not essential to measure the rotational speed. Even if rotation speed is required, it can be measured by a separate simple structure.

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2, 2a Encoder 3 Sensor 4 Harness 5 Sensor unit 6, 6a Rotating shaft unit 7, 7a Input gear 8 Output gear 9 Connection shaft 10 First encoder 11 Second encoder 12 Sensor unit 13, 13a Input shaft 14, 14a , 14b Output shaft 15 Torsion bar 16 Input side combination cylinder part 17 Output side combination cylinder part 18 Radial needle bearing 19 Stepped surface 20 End face 21, 21a-21c Thrust washer 22 Slit 23 Reinforcing cylindrical part 24a-24e Involute spline Engaging portion 25a to 25d Retaining ring 26a, 26b Cylindrical surface fitting portion 27 Stepped surface 28 Parking lock gear 29a, 29b Tapered roller bearing 30a, 30b Inner ring 31 Spacer 32a, 32b Nut 33 Stepped surface 34 Gutter 35 Core 3 6 Core metal 37 Permanent magnet 38 Permanent magnet 39 First detected part 40 Second detected part 41 Holder 42a, 42b (first, second) sensor 43 Oil introduction path 44a, 44b Oil path 45a, 45b Annular space 46a, 46b Oil groove 47 Cylindrical space 48 Tip surface 49 Step surface 50 First male involute spline part 51 First female involute spline part 52 Second male involute spline part 53 Second female involute spline part 54a, 54b Concave groove 55, 55a Input Side rotator 56, 56a Output side rotator 57 Sleeve bearing 58 Pin 59 Engagement hole 60 Oil passage 61 Input side stopper part 62 Concave part 63 Output side stopper part 64 Convex part 65 Spring part 66 Fitting part 67 Circular ring part 68 Cylinder Part 69 Large diameter part 70 Slide bearing 71 Small diameter part 72 Large diameter part

Claims (2)

A housing, a rotary shaft unit, a first gear, a second gear, a connecting shaft, a first encoder, a second encoder, and one sensor unit;
Among these, the rotary shaft unit includes both hollow first and second rotary shafts and a hollow torsion bar, and the first and second rotary shafts are concentric with each other. And is rotatably supported with respect to the housing in a state where the one end portions of the first and second rotation shafts are combined so as to be relatively rotatable. The first and second rotary shafts are concentrically arranged on the inner diameter side, and one end is connected to the first rotary shaft and the other end is connected to the second rotary shaft so as not to be relatively rotatable. And
The first gear is fixed to an axially intermediate portion of the outer peripheral surface of the first rotating shaft,
The second gear is fixed to an axially intermediate portion of the outer peripheral surface of the second rotating shaft,
Of the axially intermediate portion of the torsion bar, the axial dimension of the spring portion, which is a portion that elastically twists and deforms when transmitting torque, is greater than the axial spacing between the first and second gears. It ’s getting bigger,
The connecting shaft is disposed concentrically with the torsion bar on the inner diameter side of the torsion bar, and has one end portion relatively rotated with respect to one of the first and second rotating shafts. The other end is protruded in the axial direction from the end of the torsion bar in the state of being impossiblely connected,
The first encoder has an annular first detected portion concentric with the connecting shaft in a state of being fixed with respect to the other end portion of the connecting shaft, and has magnetic characteristics of the first detected portion. It is changed alternately and at equal pitches in the circumferential direction.
The second encoder has an annular second detected portion concentric with the other rotating shaft in a state of being fixed with respect to the other end portion of the other rotating shaft. The magnetic properties of the parts are changed alternately and at equal pitches in the circumferential direction,
The first and second detected parts are arranged close to each other,
The sensor unit is supported with respect to the housing in a state where a part of the sensor unit is opposed to the first and second detected parts, and among the first and second detected parts, The output signal is changed in response to the change in the magnetic characteristics of the part facing itself.
Torque measurement in which a sliding bearing is provided between the inner peripheral surface of the other end of the other rotating shaft and the outer peripheral surface of the fitting cylinder portion of the core metal constituting the connecting shaft or the first encoder with respect to the connecting shaft. Rotation transmission device with device. A housing, a rotary shaft unit, a first gear, a second gear, a connecting shaft, a first encoder, a second encoder, and one sensor unit;
Among these, the rotary shaft unit includes both hollow first and second rotary shafts and a hollow torsion bar, and the first and second rotary shafts are concentric with each other. And is rotatably supported with respect to the housing in a state where the one end portions of the first and second rotation shafts are combined so as to be relatively rotatable. The first and second rotary shafts are concentrically arranged on the inner diameter side, and one end is connected to the first rotary shaft and the other end is connected to the second rotary shaft so as not to be relatively rotatable. And
The first gear is fixed to an axially intermediate portion of the outer peripheral surface of the first rotating shaft,
The second gear is fixed to an axially intermediate portion of the outer peripheral surface of the second rotating shaft,
Of the axially intermediate portion of the torsion bar, the axial dimension of the spring portion, which is a portion that elastically twists and deforms when transmitting torque, is greater than the axial spacing between the first and second gears. It ’s getting bigger,
The connecting shaft is disposed concentrically with the torsion bar on the inner diameter side of the torsion bar, and has one end portion relatively rotated with respect to one of the first and second rotating shafts. The other end is protruded in the axial direction from the end of the torsion bar in the state of being impossiblely connected,
The first encoder has an annular first detected portion concentric with the connecting shaft in a state of being fixed with respect to the other end portion of the connecting shaft, and has magnetic characteristics of the first detected portion. It is changed alternately and at equal pitches in the circumferential direction.
The second encoder has an annular second detected portion concentric with the other rotating shaft in a state of being fixed with respect to the other end portion of the other rotating shaft. The magnetic properties of the parts are changed alternately and at equal pitches in the circumferential direction,
The first and second detected parts are arranged close to each other,
The sensor unit is supported with respect to the housing in a state where a part of the sensor unit is opposed to the first and second detected parts, and among the first and second detected parts, The output signal is changed in response to the change in the magnetic characteristics of the part facing itself.
A flange is provided on the outer peripheral surface of one end of the connecting shaft, and the connecting shaft is rotated relative to the one rotating shaft by press-fitting the hook into the inner peripheral surface of the other end of the one rotating shaft. A rotation transmission device with a torque measuring device that is impossiblely supported.

Images