JP2005133805A - Continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belt-type continuously variable transmission for a vehicle capable of calculating a gear shift ratio at a very low car speed without increasing the number of sensors, and determining the rotating direction. <P>SOLUTION: This continuously variable transmission comprises a pulse generating means 100 for generating pulses by detecting the change of the shape of an outer face of a movable sheave 39 of a pulley 26, the outer face has a specific shape part wherein an interval between parts corresponding to the falling of pulses when observed from the rotating direction of the pulley 26 is changed corresponding to the axial movement of the movable sheave 39, and an interval between the parts corresponding to the raising of the pulses is constant regardless of the axial movement of the movable sheave 39, and further a means for determining at least one of a rotating speed and a gear shift ratio of the pulley on the basis of the interval T1 of falling pulses generated by the pulse generating means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a continuously variable transmission, and more particularly to a vehicle belt type configured to transmit power between two variable pulleys by a belt and to control a gear ratio by changing a belt winding radius. The present invention relates to a continuously variable transmission.

  In general, a stepped or continuously variable transmission is provided on the output side of the engine for the purpose of operating the engine under optimum conditions according to the traveling state of the vehicle. An example of such a continuously variable transmission is a belt-type continuously variable transmission. This belt-type continuously variable transmission has two rotating members arranged in parallel, and a primary pulley and a secondary pulley separately attached to each rotating member. Both the primary pulley and the secondary pulley are configured by combining a fixed sheave and a movable sheave, and a V-shaped groove is formed between the fixed sheave and the movable sheave. Further, a belt is wound around the groove of the primary pulley and the groove of the secondary pulley, and a hydraulic chamber for generating a holding pressure in the axial direction is separately provided on the movable sheave. By separately controlling the hydraulic pressure in each hydraulic chamber, the groove width of the primary pulley is controlled to change the belt wrapping radius and the gear ratio is changed, while the groove width of the secondary pulley is changed. The belt tension is controlled.

  By the way, in the belt-type continuously variable transmission as described above, from conditions such as data stored in the controller (for example, an optimal fuel consumption curve with engine speed and throttle opening as parameters), vehicle speed, and accelerator opening. Based on the determined acceleration request of the vehicle, the gear ratio and the clamping pressure are controlled so that the engine operating state becomes the optimum state. Specifically, the groove width of the primary pulley is adjusted by controlling the hydraulic pressure in the hydraulic chamber of the hydraulic actuator. As a result, the belt winding radius in the primary pulley changes, and the ratio between the input rotation speed and the output rotation speed of the belt-type continuously variable transmission, that is, the gear ratio is controlled steplessly (continuously). In order to reliably control such a gear ratio, it is necessary to accurately grasp the actual gear ratio, and an example of a belt type continuously variable transmission for that purpose is patented. It is described in Document 1.

  In the belt-type continuously variable transmission described in Patent Document 1, the rotational speed of the input shaft and the rotational speed of the output shaft are detected by a rotational speed sensor, and the speed ratio is calculated based on the detected values of both. I have to.

  In the belt-type continuously variable transmission described in Patent Document 2, the amount of movement of the movable pulley in the input shaft or the output shaft in the axial direction is detected by a position (stroke) sensor, and an actual shift is performed based on the detected value. The ratio is calculated from the correlation data, and the correlation data is self-corrected with the rotation ratio calculated from the rotation speed ratio between the driving pulley and the driven pulley.

  Furthermore, in the belt-type continuously variable transmission described in Patent Document 3, a triangular, sawtooth or similar pattern is provided on the outer peripheral surface of the axially movable disk, and a signal is transmitted to the induction sensor by this pattern. Thus, both the rotational speed information of the axially movable disk and the information on the axial position can be read.

Japanese Utility Model Publication No. 5-49451 JP 7-158706 A Japanese National Patent Publication No. 8-511330

  By the way, in the belt-type continuously variable transmission described in Patent Document 1, the input shaft rotational speed and the output shaft rotational speed are detected by the rotational speed sensor, respectively. Since the rotational speed on the shaft side is extremely low, it is impossible to accurately detect the rotational speed, and it is difficult to accurately calculate the gear ratio.

  Further, in the belt-type continuously variable transmission described in Patent Document 2, calculation of the gear ratio at an extremely low vehicle speed is improved, but a separate position sensor is required, so that the cost increases accordingly. There was a problem.

  Furthermore, in the belt type continuously variable transmission described in Patent Document 3, a signal is generated in the induction sensor by a pattern, and both the rotational speed information of the axially movable disk and the information on the axial position are obtained. Since it can be read, it can be evaluated in that it is not necessary to calculate the gear ratio at an extremely low vehicle speed and to increase the number of sensors. However, since only the pulses having the same waveform can be obtained, there is a problem that the rotation direction cannot be determined.

  The present invention has been made against the background of the above circumstances, and it is possible to calculate a gear ratio at an extremely low vehicle speed without increasing the number of sensors and to determine the rotational direction of the vehicle. It aims to provide a belt type continuously variable transmission.

  In order to achieve the above object, a continuously variable transmission according to an aspect of the present invention includes pulse generation means for generating a pulse by detecting a shape change of a surface that moves in the axial direction together with a pulley movable portion, and generates a pulse. On the surface detected by the means, the distance between the portions corresponding to either the rising or falling of the pulse is changed corresponding to the axial movement of the pulley movable portion when viewed in the rotation direction of the pulley, In addition, a predetermined shape portion is provided in which the interval between the portions corresponding to either the rising or falling edge of the pulse is constant regardless of the axial movement of the pulley movable portion, and the pulse generated by the pulse generating means Means is provided for obtaining at least one of the rotational speed or the gear ratio of the pulley based on the interval between the rising edge and the falling edge.

  Here, the predetermined shape portion is defined by a first shape portion having a constant interval in the axial direction, an edge portion parallel to the first shape portion, and an edge portion changing in accordance with the axial movement. In addition, at least one second shape portion may be included and arranged at a predetermined cycle.

  In addition, the predetermined shape portion is defined by a first shape portion having a constant interval in the axial direction, an edge portion parallel to the first shape portion, and an edge portion changing in accordance with the axial movement. A plurality of second shape portions may be included and arranged at a predetermined cycle.

  Further, the predetermined shape portion has a first shape portion having a constant interval in the axial direction, an edge portion parallel to the first shape portion, and an edge portion that changes corresponding to the axial movement. Including at least one two shape portions and at least one first shape portion having a constant interval in the axial direction and at least one third shape portion having a constant interval at both edge portions that change in accordance with the axial movement; You may arrange | position by the period.

  The predetermined shape portion is defined by a first shape portion having a constant interval in the axial direction, an edge portion parallel to the first shape portion, and an edge portion changing in accordance with the axial movement. A plurality of two shape portions, a first shape portion having a constant interval in the axial direction, a plurality of third shape portions having a constant interval at both edge portions that change corresponding to the axial movement, and at a predetermined cycle It may be arranged.

  According to one aspect of the present invention having the above-described configuration, the surface detected by the pulse generating means has an interval between portions corresponding to either rising or falling of the pulse as viewed in the rotation direction of the pulley. Is a predetermined shape part that changes corresponding to the axial movement of the pulley movable part, and the interval between the parts corresponding to either the rising or falling of the pulse is constant regardless of the axial movement of the pulley movable part Therefore, the pulse generating means generates a pulse by detecting the shape change of the surface moving in the axial direction together with the pulley movable portion. The pulse interval corresponding to the predetermined shape portion is either a pulse interval corresponding to the gear ratio at that time or a constant pulse interval regardless of the gear ratio at that time, depending on the rotation direction of the pulley. Appear. Therefore, based on the appearance of the pulse interval of the predetermined shape portion, at least one of the rotational speed or the gear ratio of the pulley can be obtained and the rotational direction can be determined even at an extremely low vehicle speed without increasing the number of sensors.

  In addition, the predetermined shape portion is a first shape portion having a constant interval in the axial direction, and an interval portion is defined by an edge portion parallel to the first shape portion and an edge portion that changes corresponding to the axial movement. According to the form including at least one of the two shape portions and arranged at a predetermined cycle, it is easy to create the predetermined shape portion, and the detection pulse processing is also simplified.

  Furthermore, the predetermined shape portion is defined by a first shape portion having a constant interval in the axial direction, an edge portion parallel to the first shape portion, and an edge portion that changes in accordance with the axial movement. According to the embodiment including a plurality of two shape portions and arranged at a predetermined cycle, it is only necessary to detect the falling edge, so that an inexpensive sensor with relatively low sensitivity can be used.

  In addition, the predetermined shape portion is a first shape portion having a constant interval in the axial direction, an edge portion parallel to the first shape portion, and an edge portion that changes in response to the axial movement is a first interval. At least one or a plurality of two shape portions, a first shape portion having a constant interval in the axial direction, and at least one or a plurality of third shape portions having a constant interval at both edge portions that change corresponding to the axial movement In addition, according to the configuration including the predetermined period, it is possible to easily obtain the reverse rotation and the gear ratio at that time.

  Here, an embodiment of the present invention will be specifically described with reference to the drawings.

  FIG. 1 is a skeleton diagram when the continuously variable transmission of the present invention is applied to a transaxle of a front-wheel drive vehicle (front-wheel drive vehicle for an engine). In FIG. 1, reference numeral 1 denotes an engine as a driving force source of a vehicle, and the type thereof is not particularly limited. In the following description, a case where a gasoline engine is used as the engine 1 will be described for convenience. On the output side of the engine 1, a transaxle 3 is provided. The transaxle 3 includes a transaxle housing 4 attached to the rear end side of the engine 1 and a side opposite to the engine 1 with respect to the transaxle housing 4. A transaxle case 5 attached to the open end of the transaxle, and a transaxle rear cover 6 attached to the open end of the transaxle case 5 opposite to the transaxle housing 4 in this order. A torque converter 7 is provided inside the transaxle housing 4, and a forward / reverse switching mechanism 8, a belt type continuously variable transmission (CVT) 9, and a final one are provided inside the transaxle case 5 and the transaxle rear cover 6. A reduction gear 10 is provided.

  An input shaft 11 coaxial with the crankshaft 2 is provided inside the transaxle housing 4, and a turbine runner 13 is attached to an end of the input shaft 11 on the engine 1 side. On the other hand, a front cover 15 is connected to the rear end of the crankshaft 2 via a drive plate 14, and a pump impeller 16 is connected to the front cover 15. The turbine runner 13 and the pump impeller 16 are disposed to face each other, and a stator 17 is provided inside the turbine runner 13 and the pump impeller 16. An oil pump 20 is provided between the torque converter 7 and the forward / reverse switching mechanism 8.

  The forward / reverse switching mechanism 8 is provided in a power transmission path between the input shaft 11 and the belt type continuously variable transmission 9. The forward / reverse switching mechanism 8 has a planetary gear mechanism 24 of a double pinion type. The planetary gear mechanism 24 includes a sun gear 25 provided on the input shaft 11, a ring gear 26 disposed concentrically with the sun gear 25 on the outer peripheral side of the sun gear 25, a pinion gear 27 meshed with the sun gear 25, A pinion gear 28 meshed with the pinion gear 27 and the ring gear 26, a carrier 29 that holds the pinion gears 27, 28 so as to be able to rotate, and holds the pinion gears 27, 28 in an integrally revolving state around the sun gear 25. have. And this carrier 29 and the primary shaft 30 mentioned later of the belt-type continuously variable transmission 9 are connected. A forward clutch CL for connecting / disconnecting the power transmission path between the carrier 29 and the input shaft 11 and a reverse brake BR for controlling rotation / fixation of the ring gear 26 are provided.

  The belt type continuously variable transmission 9 includes a primary shaft (drive side shaft) 30 disposed concentrically with the input shaft 11 and a secondary shaft (driven side shaft) 31 disposed in parallel to the primary shaft 30. ing. The primary shaft 30 is rotatably held by bearings 32 and 33, and the secondary shaft 31 is rotatably held by bearings 34 and 35, respectively.

  A primary pulley 36 is provided on the primary shaft 30 side, and a secondary pulley 37 is provided on the secondary shaft 31 side. The primary pulley 36 has a fixed sheave 38 formed integrally with the primary shaft 30 and a movable sheave 39 configured to be movable in the axial direction of the primary shaft 30. A V-shaped groove 40 is formed between the opposed surfaces of the fixed sheave 38 and the movable sheave 39.

  In addition, a hydraulic actuator 41 that moves the movable sheave 39 and the fixed sheave 38 closer to and away from each other by operating the movable sheave 39 in the axial direction of the primary shaft 30 is provided. On the other hand, the secondary pulley 37 similarly has a fixed sheave 42 formed integrally with the secondary shaft 31 and a movable sheave 43 configured to be movable in the axial direction of the secondary shaft 31. A V-shaped groove 44 is formed between the surfaces facing the movable sheave 43. Further, a hydraulic actuator 45 that moves the movable sheave 43 and the fixed sheave 42 closer to and away from each other by operating the movable sheave 43 in the axial direction of the secondary shaft 31 is provided.

  A belt 46 is wound around the groove 40 of the primary pulley 36 and the groove 44 of the secondary pulley 37. The belt 46 includes a large number of metal pieces and a plurality of steel rings. A counter driven gear 47 is fixed to the secondary shaft 31 and is held by bearings 48 and 49. Further, the bearing 35 described above is provided on the transaxle rear cover 6 side, and a parking gear 31 </ b> A is provided between the bearing 35 and the secondary pulley 37.

  Further, an intermediate shaft 50 parallel to the secondary shaft 31 is supported by bearings 51 and 52 in the power transmission path between the counter driven gear 47 of the belt type continuously variable transmission 9 and the final reduction gear 10. Yes. The intermediate shaft 50 is provided with a counter driven gear 53 that meshes with the counter drive gear 47 and a final drive gear 54.

  On the other hand, the final reduction gear 10 has a hollow differential case 55 rotatably supported by bearings 56 and 57, and a ring gear 58 that meshes with the final drive gear 54 is provided on the outer periphery of the differential case 55. A pinion shaft 59 to which two pinion gears 60 are attached is disposed inside the differential case 55. Two side gears 61 are meshed with the pinion gear 60 and communicated with the wheels 63 via the left and right drive shafts 62, respectively.

  In this embodiment, a pulse is generated in the vicinity of the outer peripheral portion of the movable sheave 39 as the pulley movable portion of the primary pulley 36 by detecting a change in the shape of the outer peripheral surface or in the vicinity thereof as described in detail below. A rotation sensor 100 is disposed as a pulse generating means. The rotation sensor 100 may be composed of an electromagnetic pickup or a photoelectric pickup.

  The transaxle 3 is connected to a controller (not shown) that controls the entire vehicle. The controller is a microcomputer mainly composed of an arithmetic processing unit (CPU or MPU), a storage unit (RAM and ROM), and an input / output interface. It is configured. For this controller, various parameters indicating the operating state of the engine 1, for example, engine speed, accelerator opening, throttle opening sensor signal, various parameters indicating the state of the transaxle 3, such as torque Information such as the torque ratio of the converter 7, the rotational speed Nin of the input shaft 30 and the rotational speed Nout of the output shaft 31, and the vehicle speed V are input as signals of various sensors and calculation results, and are obtained in advance through experiments or the like. Based on the map or the like, the required gear ratio γ (= Nin / Nout) and the belt clamping pressure are controlled.

  Further, the controller also stores data for performing shift control of the engine 1, the lockup clutch 19, and the belt type continuously variable transmission 9 based on various signals. For example, by controlling the gear ratio of the belt-type continuously variable transmission 9 based on the traveling state such as the accelerator opening and the vehicle speed, data for selecting the optimum operating state of the engine 1 or the accelerator opening A lock-up clutch control map with the speed and vehicle speed as parameters is stored in the controller, and the lock-up clutch 19 is controlled to each of engagement / release / slip states based on the lock-up clutch control map. Based on various signals input to the controller and data stored in the controller, a control signal is output from the controller to the fuel injection control device, the ignition timing control device, and the hydraulic control device.

  The belt type continuously variable transmission 9 is a vehicle acceleration determined from conditions such as data stored in a controller (for example, an optimum fuel consumption curve with engine speed and throttle opening as parameters), vehicle speed, and accelerator opening. Based on the request and the like, the gear ratio and the clamping pressure are controlled so that the operating state of the engine 1 becomes an optimum state. Specifically, the width of the groove 40 of the primary pulley 36 is adjusted by controlling the hydraulic pressure in the hydraulic chamber of the hydraulic actuator 41. As a result, the winding radius of the belt 46 in the primary pulley 36 changes, and the ratio between the input rotation speed and the output rotation speed of the belt-type continuously variable transmission 9, that is, the gear ratio is controlled steplessly (continuously). .

  Furthermore, by controlling the hydraulic pressure of the hydraulic actuator 45, the width of the groove 44 of the secondary pulley 37 changes. That is, the clamping force (in other words, thrust) in the axial direction of the secondary pulley 37 with respect to the belt 46 is controlled. The tension of the belt 46 is controlled by this clamping pressure, and the contact surface pressure between the primary pulley 36 and the secondary pulley 37 and the belt 46 is controlled. The hydraulic pressure of the hydraulic actuator 45 is controlled based on the torque input to the belt type continuously variable transmission 9 and the gear ratio of the belt type continuously variable transmission 9. The torque input to the belt type continuously variable transmission 9 is determined based on the engine speed, the throttle opening, the torque ratio of the torque converter 7, and the like.

(1) First Embodiment First, a first embodiment of the present invention will be described with reference to FIGS. In the first embodiment, as shown in the development view of FIG. 2, the rectangular convex portion 110 and the second shape portion as the first shape portion are formed on the outer peripheral surface of the movable sheave 39 of the primary pulley 36. The trapezoidal convex portions 120 are alternately arranged at a constant pitch P. The leading edge 110L and the trailing edge 110T of the rectangular protrusion 110 are parallel to the axes of the primary pulley 36 and the primary shaft 30 and have a certain width or interval 110S. On the other hand, the trapezoidal convex portion 120 has a leading edge 120L parallel to the leading edge 110L of the rectangular convex portion 110, and the trailing edge 120T is inclined at a predetermined angle with respect to the axis or the leading edge 120L. . Thus, by arranging the rectangular convex portion 110 and the trapezoidal convex portion 120, the portions corresponding to the falling edges of the pulses in the rotation sensor 100 as viewed in the rotation direction of the pulley 36 (this In the embodiment, the interval between the trailing edge 110T and the trailing edge 120T changes corresponding to the axial movement of the movable sheave 39, which is the pulley movable portion, and the portions corresponding to the rising edge of the pulse (this embodiment) Then, a predetermined shape portion is formed in which the interval between the leading edge 110L and the leading edge 120L) is constant regardless of the axial movement of the pulley movable portion. And this predetermined shape part is arrange | positioned by the predetermined period.

Therefore, when the primary pulley 36 rotates, a change in the shape of the outer peripheral surface of the movable sheave 39 is detected, and the rotation sensor 100 generates a pulse. For example, as shown in FIG. 3A, when the movable sheave 39 is moved in the axial direction to the minimum gear ratio (γ = min) position where the width of the groove 40 of the primary pulley 36 is minimized, the rotation sensor 100 is A pulse as shown in FIG. 3B is generated. On the other hand, for example, as shown in FIG. 4A, when the movable sheave 39 is moved in the axial direction to the maximum gear ratio (γ = max) position where the width of the groove 40 of the primary pulley 36 is maximum, the rotation sensor 100 generates a pulse as shown in FIG. That is, the falling t ₂ of pulses corresponding to the trailing edge 120T of the first trapezoidal protrusion 120 from the falling t ₁ of the pulse corresponding to the first trailing edge 110T of the rectangular convex part 110 time T1 Although appearing later, the pulse falling t ₁ corresponding to the trailing edge 110T of the next rectangular convex 110 from the pulse falling t ₁ corresponding to the trailing edge 110T of the _first rectangular convex 110 is shown. ₃ appears after time T0. Here, the time T0 depends on the rotational speed of the primary pulley 36, but is constant at a certain rotational speed, whereas the time T1 is apparent when comparing FIG. 3B and FIG. 4B. Furthermore, it changes according to the moving position of the movable sheave 39 in the axial direction. Therefore, by obtaining T1 / T0, the movement position in the axial direction of the movable sheave 39 and, consequently, the gear ratio is obtained from a preset relationship with the inclination angle of the trailing edge 120T of the trapezoidal convex portion 120. It will be done. The rotational speed of the primary pulley 36 can be easily calculated by the number of the above-described times T0 appearing per predetermined unit time because the number of the rectangular protrusions 110 provided is known.

Meanwhile, the primary pulley 36 when rotated in the reverse direction, as shown in FIG. 4 (C), from the pulse fall t _r1 that corresponds to the leading edge 110L of the rectangular protrusion 110 of trapezoidal protrusions 120 pulse falling _{t r2} of which corresponds to the leading edge 120L, and correspond from the falling _{t r2} of pulses corresponding to the leading edge 120L of the projections 120 of trapezoidal leading edge 110L of the next rectangular convex portion 110 The falling _{edge tr3 of the} pulse always appears as a constant value T0 / 2. Therefore, when this constant value T0 / 2 is obtained, it is determined that the primary pulley 36 is rotating in the reverse direction.

In the above-described embodiment, the case where a relatively inexpensive sensor mainly having the detection capability of the falling shape portion is used as the rotation sensor 100 used is described. However, the sensitivity is higher and the detection of the rising shape portion is performed. In the case of using a sensor that also has a capability, the pulse rise t _R corresponding to the leading edge 120L of the trapezoidal convex portion 120 and the pulse fall t _D corresponding to the trailing edge 120T are simply calculated from the following. as shown in FIG. 4 (C), by detecting the time T _V, it is possible to obtain the gear ratio. Further, the reverse rotation of the primary pulley 36 can also be determined by the above-described constant value T0 / 2.

(2) Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the same functional part as previous embodiment, and duplication description is avoided. In the second embodiment, a rectangular convex portion 110 and a second shape portion as the first shape portion are formed on the outer peripheral surface of the movable sheave 39 of the primary pulley 36 as shown in the development view of FIG. A plurality of trapezoidal convex portions 120 (two in this example) are arranged at a constant pitch P. Like the first embodiment, the leading edge 110L and the trailing edge 110T of the rectangular protrusion 110 are parallel to the axes of the primary pulley 36 and the primary shaft 30, and have a certain width or interval 110S. Yes. On the other hand, the trapezoidal convex portion 120 also has a leading edge 120L parallel to the leading edge 110L of the rectangular convex portion 110, and the trailing edge 120T is parallel to the leading edge 120L, as in the first embodiment. It is inclined at a predetermined angle.

  Thus, by arranging the rectangular convex portion 110 and the two trapezoidal convex portions 120 as one set, it corresponds to the falling of the pulse at the rotation sensor 100 when viewed in the rotation direction of the pulley 36. The distance between the two parts (in this embodiment, the trailing edge 110T and the two trailing edges 120T) changes corresponding to the axial movement of the movable sheave 39, which is the pulley movable part, and the rise of the pulse A predetermined shape portion is formed in which the distance between two corresponding portions (in this embodiment, the leading edge 110L and the two leading edges 120L) is constant regardless of the axial movement of the pulley movable portion. And this predetermined shape part is arrange | positioned by the predetermined period (namely, every 3P).

Therefore, when the primary pulley 36 rotates, a change in the shape of the outer peripheral surface of the movable sheave 39 is detected, and the rotation sensor 100 generates a pulse. For example, as shown in FIG. 6A, when the movable sheave 39 is moved in the axial direction to the minimum gear ratio (γ = min) position where the width of the groove 40 of the primary pulley 36 is minimized, the rotation sensor 100 is A pulse as shown in FIG. 6B is generated. On the other hand, for example, as shown in FIG. 7A, when the movable sheave 39 is moved in the axial direction to the maximum gear ratio (γ = max) position where the width of the groove 40 of the primary pulley 36 is maximum, the rotation sensor 100 generates a pulse as shown in FIG. That is, the pulse falling t ₂ corresponding to the trailing edge 120 T of the first trapezoidal convex part 120 from the falling edge t _{1 of the} pulse corresponding to the trailing edge 110 T of the first rectangular convex part 110 is time. appeared after T1, emerge from the falling t ₂ after the second falling t ₃ of pulses corresponding to the trailing edge 120T of the trapezoidal protrusion 120 is time T2, further from the falling t ₃ of the second falling t ₄ of pulses corresponding to the trailing edge 110T of the rectangular convex part 110 to appear after a time T3, falling t of pulses corresponding to the first trailing edge 110T of the rectangular convex portion 110 falling t ₄ of pulses corresponding to ₁ to the second and is next trailing edge 110T of the rectangular convex portion 110 appears after time T0.

  Here, the time T0 depends on the rotational speed of the primary pulley 36, but is constant at a certain rotational speed, whereas the time T1 and the time T3 vary depending on the moving position of the movable sheave 39 in the axial direction. That is, the time T2 is constant regardless of the gear ratio, but the time T1 increases as the gear ratio increases and the time T3 decreases conversely. Therefore, by calculating T1 / T0 or T3 / T0, from the preset relationship with the inclination angle of the trailing edge 120T of the trapezoidal convex part 120, the rotational speed and the moving position of the movable sheave 39 in the axial direction, As a result, a gear ratio is required.

On the other hand, when the primary pulley 36 rotates in the reverse direction, as shown in FIGS. 6C and 7C, the pulse from the falling _tr 1 of the pulse corresponding to the leading edge 110L of the rectangular protrusion 110 is one. pulses th falling _{t r2} of pulses corresponding to the leading edge 120L of trapezoidal protrusions 120 appeared after a time T3, corresponding from the falling _{t r2} to the second leading edge of the trapezoidal protrusion 120 120L falling _{t r3} appeared after a time T2 of further but emerges from the falling _{t r3} after pulse falling _{t r4} the time T1 corresponding to the leading edge 110L of the next rectangular convex portion 110, these time T1, T2 and T3 are always constant corresponding to the pitch P described above. Further, the time T0 of the first rectangular pulse falling _{t r4} of the pulse falling _{t r1} that corresponds to the leading edge 110L of the convex portions 110 corresponding to the leading edge 110L of the next rectangular convex portion 110 constant Therefore, T1 / T0, T2 / T0, and T3 / T0 are also constant values, whereby it is determined that the primary pulley 36 is rotating in the reverse direction.

  The above-described times T1, T2, and T3 can take the same value during the forward rotation of the primary pulley 36 at a certain gear ratio, but reverse rotation occurs during shift control in the forward rotation in the continuously variable transmission 9. Since it cannot be, there is no misclassification. In the present embodiment, any sensor that can detect only the falling edge may be used as the rotation sensor 100, so that a relatively inexpensive sensor is used to detect a gear ratio from an extremely low vehicle speed and to detect reverse rotation. Is possible.

(3) Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the same functional part as previous embodiment, and duplication description is avoided. In the third embodiment, as shown in the development view of FIG. 8, the rectangular convex portion 110 as the first shape portion and the second shape portion are provided on the outer peripheral surface of the movable sheave 39 of the primary pulley 36. In addition to a plurality of trapezoidal convex portions 120 (two in this example) arranged as a first set at a constant pitch P, a rectangular convex portion 110 as the first shape portion is provided. A plurality of parallelogram-shaped convex portions 130 as the third shape portion (two in this example) are arranged in a second set at a constant pitch P.

  Like the first and second embodiments, the leading edge 110L and the trailing edge 110T of the rectangular convex portion 110 are parallel to the axes of the primary pulley 36 and the primary shaft 30, and have a constant width or interval 110S. Have. On the other hand, the trapezoidal convex portion 120 also has the leading edge 120L parallel to the leading edge 110L of the rectangular convex portion 110, and the trailing edge 120T is the leading edge, as in the first and second embodiments. It is inclined at a predetermined angle with respect to 120L. Further, the parallelogram-shaped convex portion 130 as the third shape portion has a leading edge 110L and a trailing edge 130L and a trailing edge 130T with a constant interval between both edge portions, and a leading edge 110L and a trailing edge of the rectangular convex portion 110. It is inclined at a predetermined angle with respect to the edge 110T.

  In this way, the first pair of rectangular convex portions 110 and two trapezoidal convex portions 120 and the second pair of rectangular convex portions 110 and two parallelogram-shaped convex portions 130 are alternately arranged. By being provided, a predetermined shape portion is configured. That is, when viewed in the rotation direction of the primary pulley 36, the interval between the two portions (in this embodiment, the trailing edge 110T and the two trailing edges 120T) corresponding to the falling of the pulse at the rotation sensor 100 is the pulley. The distance between the two parts (in this embodiment, leading edge 110L and two leading edges 120L) that change corresponding to the axial movement of the movable sheave 39, which is a movable part, and that corresponds to the rising edge of the pulse is movable by the pulley. A predetermined shape portion is formed which is constant regardless of the axial movement of the portion. And this predetermined shape part is arrange | positioned by the predetermined period (namely, every 3P).

  Therefore, when the primary pulley 36 rotates, a change in the shape of the outer peripheral surface of the movable sheave 39 is detected, and the rotation sensor 100 generates a pulse. For example, as shown in FIG. 9A, when the movable sheave 39 is moved in the axial direction to the minimum gear ratio (γ = min) position where the width of the groove 40 of the primary pulley 36 is minimized, the rotation sensor 100 is A pulse as shown in FIG. 9B is generated. On the other hand, for example, as shown in FIG. 10A, when the movable sheave 39 is moved in the axial direction to the maximum gear ratio (γ = max) position where the width of the groove 40 of the primary pulley 36 is maximum, the rotation sensor 100 generates a pulse as shown in FIG.

That is, in the first set, the fall of the pulse corresponding the falling t ₁ of the pulse corresponding to the trailing edge 110T of the rectangular convex portion 110 to a first trailing edge of the trapezoidal protrusion 120 120T t ₂ appears after time T 1, and the falling edge t ₃ of the pulse corresponding to the trailing edge 120 T of the second trapezoidal convex part 120 from this falling t ₂ appears after time T ₂ , and this falling t ₃ the second falling t ₄ of pulses corresponding to the trailing edge 110T of the rectangular convex part 110 to appear after a time T3, corresponding to the first set of the trailing edge of the rectangular convex portion 110 110T from falling t ₄ of pulses corresponding the falling t ₁ of the pulse to the second pair of trailing edge 110T of the rectangular convex portion 110 which appears after a time T0.

On the other hand, in the second set, pulses corresponding to the trailing edge 130T of the trailing pulse falling t ₄ from a second parallelogram-shaped convex portions 130 that correspond to edges 110T of rectangular convex portion 110 of the above falling t ₅ appeared after a time T1 of, emerges from the falling t ₅ to the second falling t ₆ of pulses corresponding to the trailing edge 130T of the parallelogram-shaped convex portion 130 after time T2, further, the falling t fall t ₇ pulses corresponding to the trailing edge 110T of the next rectangular convex portion 110 from ₆ appears after a time T3. Incidentally, the pulse corresponding to the second set of the trailing edge 110T of the rectangular convex portion 110 of the trailing pulse of the falling t ₄ following the first set of rectangular convex portion 110 from the corresponding to the edge 110T standing down _{t 7} it will appear after the time T0.

  Here, the time T0 depends on the rotational speed of the primary pulley 36 as described above, but is constant at a certain rotational speed, whereas the time T1 and the time T3 in the first and second groups are movable sheaves 39. It changes according to the movement position in the axial direction. That is, the time T2 is constant regardless of the gear ratio, but the time T1 increases as the gear ratio increases, and the time T3 decreases conversely. Therefore, by calculating T1 / T0 or T3 / T0, it is possible to obtain a forward rotation from the preset relationship between the inclination angles of the trailing edges 120T and 130T of the trapezoidal convex portion 120 and the parallelogram-shaped convex portion 130. Thus, the moving position of the movable sheave 39 in the axial direction, that is, the gear ratio, is obtained.

On the other hand, when the primary pulley 36 rotates in the reverse direction, as shown in FIGS. 9C and 10C, the falling of the pulse corresponding to the leading edge 110L of the first set of rectangular protrusions 110 is performed. t falling _{t r2} of pulses from _r1 corresponding to a first parallelogram shaped convex portion 130 leading edge 130L appeared after a time T3, the leading edge from the trailing _{t r2} second parallelogram-shaped convex portion 130 The fall t _r3 of the pulse corresponding to 130L appears after time T2, and further, the fall t _r4 of the pulse corresponding to the leading edge 110L of the second set of rectangular convex portions 110 from this _fall t _r3 is time T1. Will appear later. Furthermore, the falling t _r4 from a second pulse falling t _r5 of which corresponds to the leading edge 120L of trapezoidal protrusions 120 appeared after a time T3, the convex portion from the falling t _r5 of the second trapezoidal 120 pulses falling _{t r6} of which corresponds to the leading edge 120L of appeared after time T2, further falling t of pulses corresponding from the falling _{t r6} to the first set of leading edge of the rectangular convex portion 110 110L _r7 appears after time T1.

  By the way, these times T1, T2 and T3 are always constant corresponding to the above-mentioned pitch P in the first set. On the other hand, in the second set, the time T2 is constant regardless of the gear ratio, but the time T1 increases as the gear ratio increases, and the time T3 decreases conversely. As a result, it is determined that the primary pulley 36 is rotating in the reverse direction, and at the same time, the moving position of the movable sheave 39 in the axial direction during the reverse rotation from T1 / T0 or T3 / T0 in the second set, and thus the gear ratio. Is easily required.

  In the above-described embodiment, an example in which a rectangular shape, a trapezoidal shape, and a parallelogram-shaped convex portion are formed as the predetermined shape portion has been described, but those edge portions are detected as the rising edge or falling edge of the pulse by the rotation sensor 100. Of course, it may be formed by a groove or a recess as long as it is possible.

  In addition, when forming the predetermined shape portion, an example of a trapezoidal convex portion having a linear trailing edge inclined by a predetermined angle with respect to the leading edge parallel to the axis line is shown, but this trailing edge is limited to a straight line. Instead, it may be a curve as long as the interval between the portions corresponding to the falling edge of the pulse changes in a predetermined relationship corresponding to the axial movement of the movable sheave.

  Furthermore, in the above-described embodiment, the predetermined shape portion is formed on the outer periphery of the movable sheave. However, this may be at another position as long as it can rotate with the movable sheave and move in the axial direction together with the movable sheave. . For example, by extending a cylindrical plate along the outer periphery of the movable sheave and forming a convex or concave portion such as the aforementioned rectangular shape, trapezoidal shape, parallelogram shape, or the like on the plate, or by cutting out such a shape, You may form.

  In the above embodiment, the example in which the rotation sensor 100 is provided only on the primary pulley 36 side has been described. However, the transmission ratio may be obtained by providing the rotation sensor 100 only on the secondary pulley 37 side. Further, by providing both the primary pulley 36 side and the secondary pulley 37 side, a gear ratio that takes into account the slip of the belt 46 may be obtained.

It is a skeleton figure which shows the transaxle to which the continuously variable transmission of this invention is applied. It is an expanded view which shows the outer peripheral surface of the pulley movable part concerning 1st embodiment of this invention. (A) is a side view showing the positional relationship between the primary pulley at the minimum gear ratio position and the rotation sensor, and (B) is a diagram showing a pulse train generated at that time. (A) is a side view showing the positional relationship between the primary pulley at the maximum gear ratio position and the rotation sensor, and (B) and (C) are diagrams showing pulse trains generated at that time. It is an expanded view which shows the outer peripheral surface of the pulley movable part concerning 2nd embodiment of this invention. (A) is a side view showing the positional relationship between the primary pulley and the rotation sensor at the minimum gear ratio position, (B) is a pulse train generated by forward rotation at that time, and (C) is a pulse train generated by reverse rotation. FIG. (A) is a side view showing the positional relationship between the primary pulley and the rotation sensor at the maximum gear ratio position, (B) is a pulse train generated by forward rotation at that time, and (C) is a pulse train generated by reverse rotation. FIG. It is an expanded view which shows the outer peripheral surface of the pulley movable part concerning 3rd embodiment of this invention. (A) is a side view showing the positional relationship between the primary pulley and the rotation sensor at the minimum gear ratio position, (B) is a pulse train generated by forward rotation at that time, and (C) is a pulse train generated by reverse rotation. FIG. (A) is a side view showing the positional relationship between the primary pulley and the rotation sensor at the maximum gear ratio position, (B) is a pulse train generated by forward rotation at that time, and (C) is a pulse train generated by reverse rotation. FIG.

Explanation of symbols

30 Primary shaft 31 Secondary shaft 36 Primary pulley 37 Secondary pulley 38 Primary side fixed sheave 39 Primary side movable sheave 42 Secondary side fixed sheave 43 Secondary side movable sheave 100 Rotation sensor

Claims (5)

A pulse generating means for generating a pulse by detecting a shape change of the surface moving in the axial direction together with the pulley movable portion;
On the surface detected by the pulse generating means, the interval between the portions corresponding to either the rising or falling of the pulse changes in accordance with the axial movement of the pulley movable portion when viewed in the rotation direction of the pulley. And a predetermined shape portion is provided in which the interval between the portions corresponding to the other one of the rising edge and the falling edge of the pulse is constant regardless of the axial movement of the pulley movable portion,
A continuously variable transmission, comprising: means for obtaining at least one of a rotational speed and a gear ratio of the pulley based on an interval between one of rising and falling edges of the pulse generated by the pulse generating means.   The predetermined shape portion includes a first shape portion having a constant interval in the axial direction, and a second shape in which an interval is defined by an edge portion parallel to the first shape portion and an edge portion that changes in response to the axial movement. The continuously variable transmission according to claim 1, wherein the continuously variable transmission includes at least one shape portion and is arranged at a predetermined cycle.   The predetermined shape portion includes a first shape portion having a constant interval in the axial direction, and a second shape in which an interval is defined by an edge portion parallel to the first shape portion and an edge portion that changes in response to the axial movement. The continuously variable transmission according to claim 1, wherein the continuously variable transmission includes a plurality of shape portions and is arranged at a predetermined cycle.   The predetermined shape portion includes a first shape portion having a constant interval in the axial direction, a second shape in which an interval is defined by an edge portion parallel to the first shape portion and an edge portion that changes in accordance with the axial movement. At least one portion and a first shape portion having a constant interval in the axial direction, and at least one third shape portion having a constant interval at both edge portions that change corresponding to the axial movement, at a predetermined cycle The continuously variable transmission according to claim 1, wherein the continuously variable transmission is provided. The predetermined shape portion includes a first shape portion having a constant interval in the axial direction, a second shape in which an interval is defined by an edge portion parallel to the first shape portion and an edge portion that changes in accordance with the axial movement. 1st shape part having a plurality of parts and a constant interval in the axial direction, and a plurality of third shape parts having a constant interval at both edge parts that change corresponding to the axial movement, and arranged at a predetermined cycle The continuously variable transmission according to claim 1, wherein the continuously variable transmission is provided.

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