JPWO2013057833A1 - Pulley mechanism of belt type continuously variable transmission for vehicle - Google Patents

Abstract

Provided is a pulley mechanism for a belt-type continuously variable transmission for a vehicle that can increase the coupling rigidity between a rotating shaft and a fixed sheave without increasing the shaft length of the belt-type continuously variable transmission. Since the first fixing portion 96 and the second fixing portion 98 are provided on both sides of the stepped portion 92, the fixing sheave 68 is fixed by the first fixing portion 96 and the second fixing portion 98. The coupling rigidity between 68 and the output shaft 40 increases. Further, since the belt reaction force at the time of power transmission can be received by the first fixing portion 96 and the second fixing portion 98, the amount of inclination of the fixed sheave 68 at the time of power transmission is also suppressed, and the belt-type continuously variable transmission 18 Decrease in torque capacity and transmission efficiency, and deterioration of NV characteristics can be suppressed.

Description

  The present invention relates to a pulley mechanism for a belt type continuously variable transmission for a vehicle, and more particularly to a structure of a sheave constituting the pulley mechanism.

  A pair of pulleys configured to include a fixed sheave fixed to a rotating shaft that penetrates the inner peripheral portion, a movable sheave that is not rotatable relative to the rotating shaft and is movable in the axial direction, and the pair of pulleys 2. Description of the Related Art A vehicular belt type continuously variable transmission having a wound transmission belt is well known. For example, a belt type continuously variable transmission described in Patent Document 1 is an example.

  In the belt-type continuously variable transmission of Patent Document 1, the fixed sheave and the input shaft (rotating shaft) are configured separately, and there is a technology for improving productivity by making the fixed sheave and the movable sheave common. It is disclosed.

JP 2009-204093 A

  Incidentally, as shown in FIGS. 1 to 4 of the cited document 1, the belt-type continuously variable transmission of Patent Document 1 abuts between the inner periphery of the fixed sheave and the outer periphery of the rotating shaft. Step portions for receiving a load in the thrust direction are provided, and the large diameter side is spline-fitted to prevent relative rotation between the fixed sheave and the input shaft. However, regarding the mounting structure between the fixed sheave and the rotating shaft, there is no description of a more detailed structure. For example, in the fixed sheave mounting structure of Patent Document 1, when only the small-diameter portion formed by the stepped portion is press-fitted, the axial length (press-fit span) of the portion to be press-fitted is shortened. When the fixed sheave is subjected to the belt reaction force of the transmission belt during torque transmission, the amount of inclination of the fixed sheave increases. As a result, the transmission belt is similarly inclined, resulting in a decrease in torque capacity and transmission efficiency of the belt-type continuously variable transmission, and a further deterioration in NV characteristics.

  Further, when the amount of inclination of the fixed sheave increases, a load in the direction of bending the rotating shaft acts as the fixed sheave is pressed against the rotating shaft. However, when the stepped portion is formed as in the cited reference 1, Since stress concentration tends to occur at the site, a measure to suppress the stress concentration is required. On the other hand, if the press-fit span is lengthened, the coupling rigidity increases, so these problems are solved, but the problem arises that the shaft length of the belt type continuously variable transmission becomes long. This problem similarly occurs even when the large diameter side of the stepped portion is press-fitted.

  The present invention has been made in the background of the above circumstances, and its object is to provide a fixed sheave fixed to the rotating shaft, a relative rotation impossible to the rotating shaft, and a relative movement in the axial direction. In a pulley mechanism of a belt-type continuously variable transmission for a vehicle that includes a movable sheave and is configured separately from the rotating shaft and the fixed sheave, the shaft length of the belt-type continuously variable transmission is not increased. An object of the present invention is to provide a pulley mechanism for a belt-type continuously variable transmission for a vehicle that can increase a coupling rigidity between a rotating shaft and a fixed sheave to suppress a decrease in torque capacity and transmission efficiency and a deterioration in NV characteristics.

  In order to achieve the above object, the gist of the invention according to claim 1 is that: (a) a fixed sheave that is fitted to a rotating shaft that penetrates the inner peripheral portion; A pulley mechanism for a belt-type continuously variable transmission for a vehicle, comprising: a movable sheave that is axially movable; and wherein the rotating shaft and the fixed sheave are configured separately from each other, and (b) the rotation A step portion for receiving an axial load is formed between the outer peripheral portion of the shaft and the inner peripheral portion of the fixed sheave, and the rotary shaft and the both sides of the step portion in the axial direction are formed. A first fixing portion and a second fixing portion for fixing the fixed sheave are provided.

  According to this configuration, since the first fixing portion and the second fixing portion that fix the rotating shaft and the fixed sheave are provided on both sides in the axial direction of the stepped portion, the fixing sheave is connected to the first fixing portion and the first fixing portion. It will be fixed by 2 fixing | fixed part, and the joint rigidity of a fixed sheave and a rotating shaft will increase. Further, since the belt reaction force at the time of power transmission can be received by the first fixing portion and the second fixing portion, the amount of inclination of the fixed sheave at the time of power transmission is also suppressed, and the torque capacity and transmission of the belt type continuously variable transmission are suppressed. Reduction in efficiency and deterioration of NV characteristics can be suppressed. In addition, since the step portion formed on the rotating shaft side is sandwiched in the axial direction by the first fixing portion and the second fixing portion, the belt fixing force is received by the first fixing portion and the second fixing portion. The load in the bending direction is less likely to enter the vicinity of the step portion of the rotating shaft, and the problem of stress concentration occurring at the step portion is also solved.

  Preferably, the first fixing part and the second fixing part are fixed by press-fitting. By doing so, the coupling rigidity between the rotating shaft and the fixed sheave is increased, and the belt reaction force is received by the press-fit portion of the first fixed portion and the press-fit portion of the second fixed portion, so that the inclination of the fixed sheave during power transmission The amount is also suppressed, and the decrease in torque capacity and transmission efficiency and the deterioration of NV characteristics can be suppressed. In addition, since the rotary shaft and the fixed sheave are fixed by press-fitting at the two locations of the first fixed part and the second fixed part, in order to secure the area of the press-fitted part as the press-fitted area is sufficiently secured. In addition, it is possible to prevent the belt-type continuously variable transmission from being lengthened.

  Preferably, spline teeth that mesh with each other are formed in at least one of the first fixed portion and the second fixed portion, and the spline teeth are press-fitted into each other. In this way, the relative rotation between the rotating shaft and the fixed sheave is reliably prevented, so that the reduction in transmission efficiency is further suppressed.

  Preferably, the first fixing part and the second fixing part are fixed by welding. By doing so, the coupling rigidity between the rotating shaft and the fixed sheave is increased, and the belt reaction force is received by the welded portion of the first fixed portion and the welded portion of the second fixed portion. The amount of inclination is also suppressed, and a decrease in torque capacity and transmission efficiency and a deterioration in NV characteristics can be suppressed.

  Preferably, a gap is formed in at least one corner of the step portion formed in the rotating shaft and the fixed sheave. In this way, the fixed sheave can be fitted to the rotating shaft without resistance.

1 is a skeleton diagram of a vehicle power transmission device to which the present invention is preferably applied. It is sectional drawing which shows a part of vehicle power transmission device of FIG. 1, Comprising: It is sectional drawing which shows especially the structure of a secondary pulley periphery. FIG. 3 is a partially enlarged view of FIG. 2, particularly a cross-sectional view for explaining a mechanism in which a fixed sheave is fixed to an output shaft. It is sectional drawing for demonstrating the mechanism in which a fixed sheave is fixed to the output shaft which is another Example of this invention. It is sectional drawing for demonstrating the mechanism by which a fixed sheave is fixed to the output shaft which is further another Example of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a skeleton diagram of a vehicle power transmission device 10 to which the present invention is preferably applied. In FIG. 1, a vehicle power transmission device 10 is for an FF (front engine / front drive) vehicle, and is connected to an engine 12 well known as a drive source for the vehicle. This vehicle power transmission device 10 uses a torque converter 14 that is well known as a fluid transmission device that transmits the torque of the engine 12 using a fluid as a medium, and the rotational direction of the torque transmitted from the torque converter 14 in order to advance the vehicle. The forward / reverse switching device 16 that switches between the rotation direction of the vehicle and the reverse rotation direction for reverse traveling of the vehicle, and the torque transmitted through the forward / reverse switching device 16 is converted into torque according to the load. A belt-type continuously variable transmission for a vehicle (hereinafter referred to as a continuously variable transmission) 18, a reduction gear device 20 connected to the output side of the continuously variable transmission 18, and transmission via the reduction gear device 20 A well-known so-called bevel gear type differential gear device 24 is provided which transmits the generated torque to the pair of left and right wheels 22 while allowing the rotational difference therebetween. The pump impeller 26 of the torque converter 14 is provided with a mechanical oil pump 28 that generates, for example, hydraulic pressure used for shift control of the continuously variable transmission 18 and forward / reverse switching control of the forward / reverse switching device 16. Yes.

  The forward / reverse switching device 16 is connected to the sun gear 32 connected to the turbine shaft 30 of the torque converter 14 and the input shaft 56 of the continuously variable transmission 18 and is selected with respect to the turbine shaft 30 via the forward clutch C. And a ring 34 that is selectively connected via a reverse brake B to a transaxle case 36 (hereinafter referred to as case 36) as a non-rotating member. It is mainly composed of a pinion type planetary gear device. Both the forward clutch C and the reverse brake B are hydraulic friction engagement devices that are frictionally engaged when oil pressure is supplied from the oil pump 28. In such a forward / reverse switching device 16, the forward clutch C is engaged and the reverse brake B is released, whereby the planetary gear device is brought into an integral rotation state and a forward power transmission path is established. It is like that. When the forward power transmission path is established, the torque transmitted from the torque converter 14 is output to the continuously variable transmission 18 in the same rotational direction. Further, in the forward / reverse switching device 16, the reverse brake B is engaged and the forward clutch C is released, whereby the planetary gear device is brought into the input / output reverse rotation state and the reverse power transmission path is established. It is supposed to be. When the reverse power transmission path is established, the torque transmitted from the torque converter 14 is output to the continuously variable transmission 18 with its rotational direction reversed. Further, the forward / reverse switching device 16 is set to a neutral state (blocked state) in which power transmission is blocked by releasing both the forward clutch C and the reverse brake B.

  The continuously variable transmission 18 includes a primary pulley (input-side groove width variable pulley) 58 that is provided on the outer peripheral side of the input shaft 56 and is rotatable around the axis C1, and the outer peripheral side of the output shaft 40 parallel to the input shaft 56. Is provided between the primary pulley 58 and the secondary pulley 62, and power is transmitted by frictional force between the pulleys. A well-known endless annular transmission belt 66 is provided. In the belt-type continuously variable transmission 18 configured as described above, the pulley groove of the primary pulley 58 and the pulley groove of the secondary pulley 62 are respectively changed so that the winding radius of the primary pulley 58 and the secondary pulley 62 of the transmission belt 66 is changed. By changing each of these, the gear ratio (the rotational speed of the input shaft 56 / the rotational speed of the output shaft 40) changes steplessly. When the winding radius of the primary pulley 58 of the transmission belt 66 is reduced and the winding radius of the secondary pulley 62 is increased, the speed ratio γ of the belt type continuously variable transmission 18 is increased. Further, when the winding radius of the primary pulley 58 of the transmission belt 66 is increased and the winding radius of the secondary pulley 62 is decreased, the gear ratio of the belt type continuously variable transmission 18 is decreased.

  The reduction gear device 20 is provided in parallel with the output shaft 40 and rotatably supported by a first drive gear 42 that is non-rotatably fitted to the outer peripheral surface of the output shaft 40 of the continuously variable transmission 18. A transmission shaft 44, a first driven gear 46 fitted to the outer peripheral surface of the transmission shaft 44 so as not to be relatively rotatable and meshed with the first drive gear 42, and projecting from the outer peripheral surface of the transmission shaft 44 to the outer peripheral side. The second drive gear 48 is fitted in parallel with the transmission shaft 44 and rotatably supported on the outer peripheral surface of the differential case 50 of the differential gear unit 24 so as not to rotate relative to the second drive gear 48. The second driven gear (diff ring gear) 52 is provided. The first drive gear 42 and the second drive gear 48 are formed with a smaller diameter than the first driven gear 46 and the second driven gear 52. In such a reduction gear device 20, when the vehicle is accelerated, torque transmitted from the output shaft 40 of the continuously variable transmission 18 to the first drive gear 42 is transmitted to the first driven gear 46, the transmission shaft 44, and the second drive gear 48. , And the second driven gear 52, respectively, to the differential case 50 of the differential gear unit 24. Further, when the vehicle is decelerated, the reverse driving force transmitted from the pair of left and right wheels 22 is transmitted to the output shaft 40 of the continuously variable transmission 18 via the differential gear device 24 and the reduction gear device 20.

  FIG. 2 is a cross-sectional view showing a part of the vehicle power transmission device 10 shown in FIG. 1, and in particular, a cross-sectional view showing the structure around the secondary pulley 62. As shown in FIG. 2, the secondary pulley 62 is provided on the outer peripheral side of the output shaft 40. The output shaft 40 corresponds to the rotating shaft of the present invention, and the secondary pulley 62 corresponds to the pulley mechanism of the present invention.

  The output shaft 40 is rotatably supported around the axis C2 by the case 36 via bearings 64 and 65 provided at both ends of the outer periphery in the axial direction. The secondary pulley 62 cannot rotate relative to the output shaft 40 so as to form a fixed sheave 68 fitted to the outer periphery of the output shaft 40 and a V-shaped pulley groove 70 between the fixed sheave 68. In addition, the movable sheave 72 is spline-fitted so as to be movable in the axial direction, and the movable sheave 72 is moved in the axial direction in accordance with the supplied hydraulic pressure to move the fixed sheave 68 and the movable sheave 72 closer to or away from each other. And a hydraulic actuator 74 that changes the groove width of the pulley groove 70.

  The fixed sheave 68 is an annular member fitted to the output shaft 40 penetrating the inner peripheral portion, and the fixed sheave 68 has a conical shape for forming a pulley groove 70 on the side of the movable sheave 72 in the axial direction. The sheave surface 71 is formed. In the present embodiment, the output shaft 40 and the fixed sheave 68 are not integrally formed, and are configured separately. When configured in this way, since there is no large-diameter portion when the output shaft 40 is formed by forging, the yield during molding is improved, and the heat treatment cost during hot forging is reduced. A mechanism for fixing the fixed sheave 68 to the output shaft 40 will be described later.

  The movable sheave 72 is spline-fitted so as to be movable in the axial direction with respect to the output shaft 40 and not to rotate relative to the axis C2. The movable sheave 72 includes an inner cylindrical portion 72a whose inner peripheral portion is spline-fitted to the output shaft 40, and a disk-shaped disc protruding from the end on the fixed sheave 68 side toward the outer peripheral side in the axial direction of the inner cylindrical portion 72a. A portion 72b and a cylindrical outer tube portion 72c extending in the axial direction from the outer peripheral portion of the disk portion 72b to the opposite side of the fixed sheave 68 are provided. A conical sheave surface 73 for forming the pulley groove 70 is formed in the disk portion 72b. The sheave surface 73 and the sheave surface 71 form a V-shaped pulley groove 70.

  The hydraulic actuator 74 is provided adjacent to the movable sheave 72 on the opposite side of the fixed sheave 68 in the axial direction of the movable sheave 72. The hydraulic actuator 74 includes a bottomed cylindrical cylinder member 78 for forming an oil-tight hydraulic chamber 76 together with the movable sheave 72 and the output shaft 40. The cylinder member 78 is prevented from moving in the axial direction because its inner peripheral portion is sandwiched between the stepped surface formed on the output shaft and the spacer 80. The spacer 80 is pressed against the cylinder member 78 by a nut 82 fastened to the output shaft 40 via the first drive gear 42 whose inner peripheral portion is spline-fitted to the output shaft 40. Further, the outer peripheral end of the cylinder member 78 is in sliding contact with the inner peripheral surface of the outer cylindrical portion 72c. An oil seal is fitted to the outer peripheral end of the cylinder member 78 so that the sliding contact surface with the outer cylindrical portion 72c is oil-tight.

  The cylinder member 78, the movable sheave 72, and the output shaft 40 form a hydraulic chamber 76 that is an oil-tight annular space. The hydraulic chamber 76 includes a case oil passage 84 formed in the case 36, an axial oil passage 86 formed in parallel with the shaft center C <b> 2 inside the output shaft 40 and communicating with the case oil passage 84, and a shaft method. The hydraulic oil is supplied from the oil passage 86 through the radial oil passage 88 that penetrates the output shaft 40 in the radial direction and communicates with the hydraulic chamber 76. The hydraulic oil is appropriately regulated by a hydraulic control circuit (not shown) using the hydraulic pressure discharged from the oil pump 28 as a source pressure. In addition, the movable sheave 72 is attached to the fixed sheave 68 side between the stepped end surface formed on the outer peripheral portion of the inner cylindrical portion 72 a of the movable sheave 72 and the inner peripheral wall surface of the cylinder member 78. An energizing coil spring 90 is inserted.

  In the secondary pulley 62 configured as described above, a thrust toward the fixed sheave 68 side, that is, a thrust in a direction to narrow the transmission belt 66 is applied to the movable sheave 72 according to the hydraulic pressure supplied to the hydraulic chamber 76. It has become. In FIG. 2, the secondary pulley 62 indicated by a solid line below the axis C <b> 1 shows a state in which the pulley groove 70 formed between the fixed sheave 68 and the movable sheave 72 has a minimum groove width Wmin. In this state, the winding radius of the transmission belt 66 around the secondary pulley 62 becomes maximum, and the speed ratio γ of the belt-type continuously variable transmission 18 becomes the maximum speed ratio γmax. Further, the secondary pulley 62 indicated by a solid line on the upper side of the axis C1 shows a state in which the pulley groove 70 formed between the fixed sheave 68 and the movable sheave 72 is set to the minimum groove width Wmax. In this state, the winding radius of the transmission belt 66 around the secondary pulley 62 is minimized, and the speed ratio γ of the belt-type continuously variable transmission 18 is the minimum speed ratio γmin.

  FIG. 3 is a partially enlarged view of FIG. 2, and in particular, a cross-sectional view for explaining a mechanism in which the fixed sheave 68 is fixed to the output shaft 40. As shown in FIG. 3, the output shaft 40 penetrates the inner peripheral portion of the fixed sheave 68, and the fixed sheave 68 is fitted on the outer peripheral portion of the output shaft 40 so as not to be relatively rotatable and axially movable. .

  A large-diameter shaft portion 40a and a small-diameter shaft portion 40b are formed on the outer peripheral portion of the output shaft 40 by forming a step portion 92a. In addition, a large-diameter inner peripheral portion 68a and a small-diameter inner peripheral portion 68b are formed on the inner peripheral portion of the fixed sheave 68 by forming a step portion 92b that can be fitted to the stepped portion 92a. Further, a wall surface 40c perpendicular to the axis formed by the stepped portion 92a of the output shaft 40 and a wall surface 68c perpendicular to the axis formed by the stepped portion 92b of the fixed sheave 68 are brought into contact with each other. Direction (thrust direction). The wall surface 40c and the wall surface 68c also function as a stopper for preventing the stationary sheave 68 from moving toward the bearing 64.

  Further, outer peripheral teeth 94 (spline teeth) are formed on the outer peripheral surface of the large-diameter shaft portion 40 a of the output shaft 40, and the inner peripheral teeth that mesh with the large-diameter inner peripheral portion 68 a of the fixed sheave 68. 95 (spline teeth) are formed, and these spline teeth 95 and 96 are press-fitted together. Specifically, in the large-diameter shaft portion 40a and the large-diameter inner peripheral portion 68a, the tooth surface of the tooth tip and the end of the tooth on the large-diameter side of the outer peripheral tooth 94, the root of the inner peripheral tooth 95, and the tooth at the base of the tooth The surface is fixed by so-called spline large diameter tooth surface press-fitting (hereinafter referred to as spline press-fitting). By this spline press-fitting, the coupling rigidity between the output shaft 40 and the fixed sheave 68 is increased, and the relative rotation between the output shaft 40 and the fixed sheave 68 is reliably prevented. In the present embodiment, the fixed portion by the spline press-fitting between the large-diameter shaft portion 40a and the large-diameter inner peripheral portion 68a is defined as a first fixed portion 96.

  Further, the outer peripheral portion of the small-diameter shaft portion 40b of the output shaft 40 and the inner peripheral portion of the small-diameter inner peripheral portion 68b of the fixed sheave 68 are press-fitted with each other's cylindrical surface (hereinafter referred to as cylindrical press-fitting to distinguish from spline press-fitting). ) To be fixed. In the present embodiment, a fixed portion formed by cylindrical press-fitting between the small-diameter shaft portion 40b and the small-diameter inner peripheral portion 68b is defined as a second fixed portion 98. Therefore, as shown in FIG. 3, on both sides in the axial direction of the stepped portion 92a and the stepped portion 92b (hereinafter referred to as the stepped portion 92 unless otherwise distinguished), the stepped portion 92 is sandwiched in the axial direction. A first fixing portion 96 and a second fixing portion 98 are provided.

  An annular gap 102 is formed in the corner portion 100 on the large diameter side of the stepped portion 92. For example, as shown in FIG. 3, an annular gap 102 is formed by forming a notch in an annular shape at the end of the output shaft 40 on the large diameter shaft portion 40 a side. The gap 102 may be formed by providing a cutout at the end of the fixed sheave 68 on the large-diameter inner peripheral portion 68a side, or at both ends.

  An annular gap 106 is formed in the corner 104 on the small diameter side of the step 92. For example, as shown in FIG. 3, a notch is formed in an annular shape at the end of the output shaft 40 on the small diameter shaft portion 40 b side, and a notch is also formed in an annular shape at the end of the fixed sheave 68 on the small diameter inner peripheral portion 68 b side. Thus, the gap 106 is formed. As long as the gap 106 is formed, a notch is formed at either the end of the output shaft 40 on the small diameter shaft portion 40b side or the end of the fixed sheave 68 on the small diameter inner peripheral portion 68b side. It doesn't matter.

  The operation and effect produced by fixing the fixed sheave 68 to the output shaft 40 as described above will be described. When the vehicle is in a driving state, the belt reaction force due to the transmission belt 66 being compressed by the fixed sheave 68 and the movable sheave 72 is also transmitted to the fixed sheave 68, and the belt reaction force acts in the direction in which the fixed sheave 68 is tilted. . On the other hand, on both sides in the axial direction of the stepped portion 92, there are provided the first fixed portion 96 that is spline-pressed so as to sandwich the stepped portion 92 and the second fixed portion 98 that is cylindrically pressed. The fixed sheave 68 is fixed to the output shaft 40 at two locations, and the coupling rigidity between the output shaft 40 and the fixed sheave 68 is enhanced. Accordingly, the amount of inclination of the fixed sheave 68 due to the belt reaction force is suppressed, and the decrease in torque capacity and transmission efficiency of the belt-type continuously variable transmission 18 and the deterioration of NV performance due to the inclination of the fixed sheave 68 are also suppressed. In addition, since both the first fixing portion 96 and the second fixing portion 98 are press-fitted (spline press-fitting and cylindrical press-fitting), the length of the portion to be press-fitted is not increased without increasing the shaft length of the output shaft 40 and the fixed sheave 68. A sufficient area is also secured.

  Further, the belt reaction force transmitted to the fixed sheave 68 is also transmitted to the output shaft 40 and acts perpendicularly (bending load) with respect to the axis of the output shaft 40, and the step 92 a ( There is a problem that stress concentration occurs at the corner portion 104). However, in the present embodiment, since the step portion 92a is sandwiched between the first fixing portion 96 and the second fixing portion 98, the first fixing portion 96 and the second fixing portion are fixed. The portion 98 is responsible for this belt reaction force, and it is difficult for a bending load to enter the step portion 92a sandwiched between the first fixing portion 96 and the second fixing portion 98. Accordingly, stress concentration occurring at the stepped portion 92a of the output shaft 40 is also suppressed.

  Further, since the gaps 102 and 106 are formed in the corner portion 100 and the corner portion 104, respectively, when the fixed sheave 68 is press-fitted into the output shaft 40, it can be fitted without resistance. Further, the stress concentration is also suppressed by forming the gap 106.

  As described above, according to the present embodiment, the first fixing portion 96 and the second fixing portion 98 that fix the output shaft 40 and the fixed sheave 68 are provided on both sides of the step portion 92 in the axial direction. The fixed sheave 68 is fixed by the first fixing portion 96 and the second fixing portion 98, and the coupling rigidity between the fixed sheave 68 and the output shaft 40 increases. Further, since the belt reaction force at the time of power transmission can be received by the first fixing portion 96 and the second fixing portion 98, the amount of inclination of the fixed sheave 68 at the time of power transmission is also suppressed, and the belt-type continuously variable transmission 18 Decrease in torque capacity and transmission efficiency, and deterioration of NV characteristics can be suppressed. Further, since the stepped portion 92 formed on the output shaft 40 side is sandwiched in the axial direction by the first fixing portion 96 and the second fixing portion 98, the belt reaction force is applied to the first fixing portion 96 and the second fixing portion 96. By receiving the portion 98, it is difficult for a load in the bending direction to enter the vicinity of the stepped portion 92a of the output shaft 40, and the problem of stress concentration occurring in the stepped portion 92a is also solved.

  Further, according to the present embodiment, the first fixing portion 96 and the second fixing portion 98 are fixed by press-fitting (spline press-fitting and cylindrical press-fitting). In this way, the coupling rigidity between the output shaft 40 and the fixed sheave 68 is increased, and the belt reaction force is received by the spline press-fitting of the first fixing portion 96 and the cylindrical press-fitting of the second fixing portion 98. The inclination amount of the fixed sheave 68 is also suppressed, and a decrease in torque capacity and transmission efficiency and a deterioration in NV characteristics can be suppressed. In addition, since the output shaft 40 and the fixed sheave 68 are fixed by press-fitting at two locations of the first fixing portion 96 and the second fixing portion 98, as the area to be press-fitted is ensured, the portion to be press-fitted is secured. Therefore, it is possible to prevent the belt-type continuously variable transmission 18 from being lengthened.

  In addition, according to the present embodiment, since the first fixing portion 98 is spline press-fitted, slippage between the output shaft 40 and the fixed sheave 68 is reliably prevented, so that a decrease in transmission efficiency is further suppressed.

  Further, according to the present embodiment, the gaps 102 and 106 are formed in the corner portions 100 and 104 of the step portion 92 formed in the output shaft 40 and the fixed sheave 68, respectively. In this way, the fixed sheave 68 can be fitted to the output shaft 40 without resistance.

  Next, another embodiment of the present invention will be described. In the following description, parts common to those in the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.

  FIG. 4 is a cross-sectional view for explaining a structure in which a fixed sheave 152 is fixed to an output shaft 150 in a secondary pulley 149 according to another embodiment of the present invention. When the secondary pulley 149 of the present embodiment is compared with the above-described embodiment, the first fixed portion 154 that is a fixed portion between the large-diameter shaft portion 150a of the output shaft 150 and the large-diameter inner peripheral portion 152a of the fixed sheave 152 is cylindrically press-fitted. It is fixed by. Since other structures are the same as those in the above-described embodiment, description thereof is omitted. The output shaft 150 of the present embodiment corresponds to the rotating shaft of the present invention, and the secondary pulley 149 corresponds to the pulley mechanism of the present invention.

  A large-diameter shaft portion 150a and a small-diameter shaft portion 150b are formed on the outer peripheral portion of the output shaft 150 by forming a step portion 158a. Further, a stepped portion 158b fitted to the stepped portion 158a is also formed on the inner peripheral portion of the fixed sheave 152, thereby forming a large-diameter inner peripheral portion 152a and a small-diameter inner peripheral portion 152b. The large diameter shaft portion 150a and the large diameter inner peripheral portion 152a are fixed by cylindrical press fitting, and the small diameter shaft portion 150b and the small diameter inner peripheral portion 152b are fixed by cylindrical press fitting. In this embodiment, the cylindrical press-fit portion (fixed portion) between the large-diameter shaft portion 150a and the large-diameter inner peripheral portion 152a corresponds to the first fixed portion 154, and the cylindrical press-fit between the small-diameter shaft portion 150b and the small-diameter inner peripheral portion 152b. The part (fixed part) corresponds to the second fixed part 156. Therefore, also in this embodiment, the first fixing portion 154 and the second fixing portion 156 are provided on both sides in the axial direction of the step portions (158a, 158b) so as to sandwich the step portion 158.

  Thus, even when the first fixing portion 154 is fixed by cylindrical press-fitting, it is possible to obtain substantially the same effect as in the above-described embodiment. That is, since both the first fixing portion 154 and the second fixing portion 156 are fixed by cylindrical press fitting, the coupling rigidity between the output shaft 150 and the fixed sheave 152 is increased, and the inclination amount of the fixed sheave 152 due to the belt reaction force is suppressed. The Therefore, a decrease in torque capacity and transmission efficiency due to the inclination of the fixed sheave 152 and a deterioration in NV performance are also suppressed. In addition, since the cylinder is press-fitted in both the first fixing part 154 and the second fixing part 156, the area of the press-fitted part is secured without increasing the axial length of the output shaft 150 and the fixed sheave 152. . Further, the first fixing portion 154 and the second fixing portion 156 are responsible for this belt reaction force, and the belt reaction force is applied to the step portion 158 of the output shaft 150 sandwiched between the first fixing portion 154 and the second fixing portion 156. Bending load due to becomes difficult to enter. Accordingly, stress concentration occurring at the step portion 158a of the output shaft 150 is also suppressed.

  In the above-described embodiment, the spline fitting prevents the relative rotation between the output shaft 40 and the fixed sheave 68. However, in this embodiment, since the spline fitting portion is not provided, the output shaft There is a possibility that a slip occurs between the fixed sheave 150 and the fixed sheave 152 and the transmission efficiency and the like are lowered. However, since the first fixing portion 154 is press-fitted over the entire circumferential surface, the press-fitting area is larger than the spline press-fitting that is press-fitted only with the large-diameter portion of the tooth surface as in the above-described embodiment. Coupling rigidity can be obtained and slip hardly occurs.

  As described above, in the present embodiment, the first fixing portion 154 and the second fixing portion 156 are each fixed by cylindrical press-fitting. By doing so, the coupling rigidity between the output shaft 150 and the fixed sheave 152 is increased, and the belt reaction force is received by the first fixing portion 154 and the second fixing portion 156, so that the inclination of the fixed sheave 152 during power transmission is increased. The amount is also suppressed, and a decrease in torque capacity and transmission efficiency due to the inclination of the fixed sheave 152 and a deterioration in NV characteristics can be suppressed. Therefore, in the present embodiment, substantially the same effect as that of the above-described embodiment can be obtained.

  FIG. 5 is a cross-sectional view for explaining a structure in which a fixed sheave 182 is fixed to the output shaft 180 in a secondary pulley 179 which is another embodiment of the present invention. A large-diameter shaft portion 180a and a small-diameter shaft portion 180b are formed on the outer peripheral portion of the output shaft 180 by forming a step portion 188a. In addition, a large-diameter inner peripheral portion 182a and a small-diameter inner peripheral portion 182b are formed by forming a stepped portion 188b fitted to the stepped portion 188a in the inner peripheral portion of the fixed sheave 182. In this embodiment, the fixed portion between the large diameter shaft portion 180a and the large diameter inner peripheral portion 182a corresponds to the first fixed portion 184, and the fixed portion between the small diameter shaft portion 180b and the small diameter inner peripheral portion 182b is the second fixed portion. 186. The output shaft 180 corresponds to the rotating shaft of the present invention, and the secondary pulley 179 corresponds to the pulley mechanism of the present invention.

  In the present embodiment, both the first fixing portion 184 and the second fixing portion 186 are fixed by welding. In the first fixing portion 184, the end portion on the bearing 64 side in the axial direction is laser-welded, so that the fixing sheave 182 is fixed integrally with the output shaft 180. In addition, the second fixed portion 186 is fixed to the output shaft 180 integrally with the output sheave 182 by laser welding of the end portion on the transmission belt 66 side in the axial direction. That is, both ends of the inner periphery of the fixed sheave 182 in the axial direction are fixed to the output shaft 180 by laser welding.

  As described above, even when the first fixing portion 184 and the second fixing portion 186 are fixed by laser welding, it is possible to obtain substantially the same effect as in the above-described embodiment. That is, since both the first fixing portion 184 and the second fixing portion 186 are fixed by laser welding, the coupling rigidity between the output shaft 180 and the fixed sheave 182 is increased, and the amount of inclination of the fixed sheave 182 due to the belt reaction force is also increased. It is suppressed. Accordingly, a decrease in torque capacity and transmission efficiency due to the inclination of the fixed sheave 182 and a deterioration in NV performance are also suppressed. In addition, the first fixing portion 184 and the second fixing portion 186 are responsible for this belt reaction force, and the belt reaction is applied to the stepped portion 188a of the output shaft 180 sandwiched between the first fixing portion 184 and the second fixing portion 186. Bending load due to force becomes difficult to enter. Accordingly, stress concentration occurring at the stepped portion 188a of the output shaft 180 is also suppressed.

  As described above, in the present embodiment, the first fixing portion 184 and the second fixing portion 186 are fixed by laser welding. In this way, the coupling rigidity between the output shaft 180 and the fixed sheave 182 is increased, and the belt reaction force is received by the welded portion of the first fixed portion 184 and the welded portion of the second fixed portion 186. The inclination amount of the fixed sheave 182 is also suppressed, and a decrease in torque capacity and transmission efficiency and a deterioration in NV characteristics can be suppressed. Therefore, in the present embodiment, substantially the same effect as that of the above-described embodiment can be obtained.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

  For example, each of the above-described embodiments has an independent configuration, but the embodiments may be appropriately combined within a consistent range. For example, the fixing method of the first fixing part and the second fixing part may be freely changed such that the first fixing part is press-fitted and the second fixing part is laser-welded.

  In the above-described embodiment, the first fixing portion 184 and the second fixing portion 186 fixed by laser welding are not spline-fitted, but at least one of them is a spline-fitted configuration. It doesn't matter. Moreover, the 1st fixing | fixed part 184 and the 2nd fixing | fixed part 186 may be cylindrical press-fitting or spline press-fitting in addition to laser welding.

  In the above-described embodiment, the large-diameter shaft portion 40a of the output shaft 40 and the large-diameter inner peripheral portion 68a of the fixed sheave 68 are press-fitted, but not necessarily limited to the large-diameter side. The small-diameter shaft portion 40b and the small-diameter inner peripheral portion 68b of the fixed sheave 68 may be press-fitted. Further, both of them may be spline press-fitted.

  Further, in the above-described embodiment, in the large-diameter shaft portion 40a and the large-diameter inner peripheral portion 68a, the tooth surface of the tooth tip and the end of the tooth on the large-diameter side of the outer peripheral tooth 94, and the root and tooth of the inner peripheral tooth 95 The so-called spline large-diameter tooth surface press-fitting with the original tooth surface is performed. However, the tooth bottom and the tooth surface on the small diameter side of the outer peripheral tooth 94 and the tip and end of the inner peripheral tooth 95 are formed. It may be press-fitted. Alternatively, the entire tooth surface of the outer peripheral tooth 94 and the entire tooth surface of the inner peripheral tooth may be press-fitted.

  In the above-described embodiment, the gaps 102 and 106 are formed in the stepped portion 92. However, the gaps 102 and 106 are not necessarily formed, and may be configured without a gap.

  In the above-described embodiment, the secondary pulley 62 is described as an example. However, the present invention is not limited to the secondary pulley 62 and the present invention may be applied to the primary pulley 58 side.

  Moreover, in the above-mentioned Example, although the 1st fixing | fixed part 184 and the 2nd fixing | fixed part 186 are being fixed by laser welding, other welding means, such as gas welding and plasma welding, may be applied, for example.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

18: Belt type continuously variable transmission for vehicle 40, 150, 180: Output shaft (rotating shaft)
62, 149, 179: Secondary pulley (pulley mechanism)
68, 152, 182: fixed sheave 72: movable sheave 92, 158, 188: stepped portion 96, 154, 184: first fixed portion 98, 156, 186: second fixed portion 100, 104: corner portions 102, 106: Gap

In order to achieve the above object, the gist of the invention according to claim 1 is that: (a) a fixed sheave that is fitted to a rotating shaft that penetrates the inner peripheral portion; A pulley mechanism for a belt-type continuously variable transmission for a vehicle, comprising: a movable sheave that is axially movable; and wherein the rotating shaft and the fixed sheave are configured separately from each other, and (b) the rotation A step portion for receiving an axial load is formed between the outer peripheral portion of the shaft and the inner peripheral portion of the fixed sheave, and the rotary shaft and the both sides of the step portion in the axial direction are formed. A first fixing portion and a second fixing portion for fixing the fixing sheave are provided, and the first fixing portion and the second fixing portion are fixed by press-fitting .

According to this configuration, since the first fixing portion and the second fixing portion that fix the rotating shaft and the fixed sheave are provided on both sides in the axial direction of the stepped portion, the fixing sheave is connected to the first fixing portion and the first fixing portion. It will be fixed by 2 fixing | fixed part, and the joint rigidity of a fixed sheave and a rotating shaft will increase. Further, since the belt reaction force at the time of power transmission can be received by the first fixing portion and the second fixing portion, the amount of inclination of the fixed sheave at the time of power transmission is also suppressed, and the torque capacity and transmission of the belt type continuously variable transmission are suppressed. Reduction in efficiency and deterioration of NV characteristics can be suppressed. In addition, since the step portion formed on the rotating shaft side is sandwiched in the axial direction by the first fixing portion and the second fixing portion, the belt fixing force is received by the first fixing portion and the second fixing portion. The load in the bending direction is less likely to enter the vicinity of the step portion of the rotating shaft, and the problem of stress concentration occurring at the step portion is also solved. In addition, since the first fixing portion and the second fixing portion are fixed by press-fitting, the coupling rigidity between the rotating shaft and the fixed sheave is increased, and the belt reaction force is increased by the press-fitting portion and the second fixing portion of the first fixing portion. Therefore, the amount of inclination of the fixed sheave at the time of power transmission is also suppressed, and the reduction of torque capacity and transmission efficiency and the deterioration of NV characteristics can be suppressed. In addition, since the rotary shaft and the fixed sheave are fixed by press-fitting at the two locations of the first fixed part and the second fixed part, in order to secure the area of the press-fitted part as the press-fitted area is sufficiently secured. In addition, it is possible to prevent the belt-type continuously variable transmission from being lengthened.

Claims (5)

A fixed sheave that is fitted to a rotary shaft that penetrates the inner periphery, and a movable sheave that is not rotatable relative to the rotary shaft and that is relatively movable in the axial direction, and is separate from the rotary shaft and the fixed sheave. A pulley mechanism for a belt-type continuously variable transmission for a vehicle constituted by a body,
Step portions for receiving an axial load are formed between the outer peripheral portion of the rotary shaft and the inner peripheral portion of the fixed sheave, and the rotary shaft is provided on both sides of the step portion in the axial direction. A pulley mechanism for a belt type continuously variable transmission for a vehicle, wherein a first fixing portion and a second fixing portion are provided for fixing the fixing sheave and the fixing sheave.   The pulley mechanism for a belt type continuously variable transmission for a vehicle according to claim 1, wherein the first fixing portion and the second fixing portion are fixed by press-fitting.   The belt type for a vehicle according to claim 2, wherein spline teeth that mesh with each other are formed in at least one of the first fixing portion and the second fixing portion, and the spline teeth are press-fitted into each other. Pulley mechanism for continuously variable transmission.   The pulley mechanism for a belt type continuously variable transmission for a vehicle according to claim 1, wherein the first fixing portion and the second fixing portion are fixed by welding.   The belt type continuously variable transmission for a vehicle according to any one of claims 1 to 4, wherein a gap is formed in at least one corner portion of the step portion formed in the rotating shaft and the fixed sheave. Machine pulley mechanism.

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