JP2009531610A - Torque detection device for conical pulley winding transmission - Google Patents

Abstract

A torque detection device for a conical pulley winding transmission device, the torque detection device comprising an inclined surface (32) fixedly coupled to a shaft (10) of a conical pulley pair, and a circumferential surface on the shaft. A detecting piston (36) which engages and is axially slidable and rotatable relative to the shaft and has another inclined surface (38) which is fixedly coupled thereto, and these inclinations When the torque changes between the detection piston and the shaft, the axial position of the detection piston is changed by rolling along the inclined surfaces of the plurality of spheres (40) arranged between the inclined surfaces. The torque detector further includes a guide surface (58) fixedly coupled to the movable pulley (14), and the sphere contacts the radially inner side of the guide surface. The movable pulley is not rotatable relative to the shaft and the shaft The guide surface is pressed against a fixed pulley that is fixedly slidably coupled to the shaft and immovably coupled to the shaft with a hydraulic pressure related to the axial position of the detection piston. And the radial spacing between the shaft axis and the axis of the shaft is shaped to relate to the axial spacing between the movable pulley and the fixed pulley,
The guide surface (58) has a contact point with each inclined surface (32, 38) of each sphere (40), a contact point with the guide surface (58) of the sphere, and a center point of the sphere oriented in the radial direction. It is comprised so that it may be located in 1 plane.

Description

  The present invention relates to a torque detection device for a conical pulley winding transmission.

  For example, a conical pulley winding transmission device used for an automobile generally has two conical pulley pairs, and these conical pulley pairs are wound by a winding means such as a link plate chain. By changing the distance between the conical pulleys of each conical pulley pair in the reverse direction, the transmission gear ratio can be continuously changed.

  The pair of conical pulleys preferably has a torque sensor, in particular on the drive side, by means of which the torque acting from the drive motor is detected and between the conical pulleys of the associated pulley pair. The pressure of pressure is changed corresponding to the torque.

  Such conical pulley winding transmissions with built-in torque sensors are described, for example, in German Patent Application No. 4234294, German Patent Application Publication No. 1954644, German Patent Application No. No. 4026683, German Patent Application Publication No. 19545492 and German Patent Application Publication No. 199519550.

  FIG. 4 shows a cross-sectional view of the drive side portion of the conical pulley winding transmission. An input shaft 10 formed integrally with a fixed pulley (not shown) is provided with a movable pulley 14 that is slidable in the axial direction but is coupled to the input shaft 10 so as not to rotate relative to the input shaft 10.

  On the back side of the movable pulley 14, a cylinder ring 16 is fixed in a radially outer region of the movable pulley 14 with two walls spaced apart from each other in the radial direction. In this drawing, a first pressure chamber 20 is formed on the right side of the piston 18, and a plurality of radial holes formed in the movable pulley 14 are formed in the first pressure chamber 20. 22. Supplying variable hydraulic pressure for adjusting the transmission ratio through an annular chamber 24 between the movable pulley 14 and the shaft 10, a radial hole 26 and an axial hole 28 formed in the shaft 10. Can do.

  The generally annular piston 18 is immovably coupled to a generally cup-shaped support ring 30, which is also immovably coupled to the input shaft 10. An inclined surface 32 is formed on the end surface of the support ring 30.

  Further, a detection piston 36 formed in a generally annular shape inside the support ring 30 is sealed against the peripheral surface of the input shaft 10 and the inner peripheral surface of the support ring 30 so as to be slidable in the axial direction. Has been placed. The detection piston 36 is formed with a protruding portion directed toward the movable pulley 14, and an inclined surface 38 is formed on the back side of the protruding portion, and the inclined surface 38 is the inclined surface 32. The corresponding surface is formed. A rolling element (in the illustrated embodiment, a sphere 40) is disposed between the inclined surfaces 32 and 38.

  A second pressure chamber 42 is formed between the detection piston 36 and the movable pulley 14, and hydraulic pressure is supplied to the second pressure chamber 42 via a supply conduit 44 that passes through the input shaft 10. In this case, the hydraulic medium can be led out via a lead-out conduit 46 also formed in the input shaft 10.

  The effective cross section of the supply conduit opening 48 leading to the second pressure chamber is defined by the axial position of the movable pulley 14. The effective cross section of the outlet conduit opening 50 leading from the second pressure chamber 42 is defined by the position of the detection piston 36. The detection piston 36 projects through a notch in the support ring 30 with an axial arm 52 spaced in the circumferential direction. A plurality of teeth arranged in the axial direction and the radial direction are provided on the radially outer surface of the arm 52, and these teeth are engaged with the inner teeth of the input wheel 54. Is supported on the input shaft 10 through a bearing 8 so as to be substantially non-slidable in the axial direction.

  On the radially inner side of the cylinder ring 16 that is fixedly coupled to the movable pulley 14, a ring member 56 is fixedly coupled to the cylinder ring 16, and the inner surface of the ring member 56 forms a guide surface 58. The guide surface 58 is in contact with the sphere 40, and the guide surface 58 limits the outward movement of the sphere 40 in the radial direction.

  Since the configuration and function of the apparatus described so far are known per se, only a brief description will be given below.

  When torque is applied to the detection piston 36 from the input wheel 54 that can be rotated, this torque is transmitted to the support ring 30 and the shaft 10 through the inclined surface 38, the sphere 40, and the inclined surface 32. The inclined surface is configured such that the detection piston 36 moves to the right in FIG. 1 as the torque increases, whereby the outlet conduit opening 50 is gradually closed. As the effective size of the outlet conduit opening 50 decreases, the pressure in the second pressure chamber 42 increases, so that the movable pulley 14 is subjected to a crimping pressure related to the input torque. When the movable pulley 14 is slid significantly to the left (maximum underdrive of the transmission), the second pressure chamber 42 is in a no-pressure state because the supply conduit opening 48 is closed. When the movable pulley 14 moves toward the right side in FIG. 4, the effective radius of the guide surface 58 decreases, so that the contact portion between the sphere and the inclined surface moves to the right side as the sliding movement of the movable pulley 14 increases. Towards the radially inner side, whereby the pressure in the second pressure chamber 42 is additionally changed in relation to the transmission ratio. This is because the slope of the inclined surface is related to the radial distance from the axis of the input shaft 10 at the point of contact between the sphere and the inclined surface. In this case, the gradient of the wedge surface is generally larger on the radially inner side than on the radially outer side.

In particular, the known torque detection device formed by the detection piston 36, the inclined surfaces 32 and 38, the guide surface 58 and the sphere 40 has the following characteristics. That is:
The centrifugal force acting on the sphere 40 increases as the rotational speed of the input shaft 10 increases, and this centrifugal force is generally not completely accepted by the reaction force of the inclined surface and the guide surface; The pressure in the chamber 42 is related to the rotational speed. This can also cause slippage or overload or hysteresis of the conical pulley winding transmission.
-In the case of the slope of a circumferentially inclined surface related only to the distance from the axis of the input shaft 10 (the relationship in the radial direction), the perpendicular to the rolling surface on which the sphere rolls against the inclined surface is Has ingredients. Accordingly, the center point of the sphere and the contact point between the sphere and the inclined surface are located on different radii. This difference is approximately proportional to the axial sliding of the detection piston. As a result, the ratio between the crimping pressure (pressure in the second pressure chamber) and the torque is not only related to the transmission ratio, but also the volumetric flow and back of the hydraulic medium flowing through the second pressure chamber 42. It is also related to pressure and torque.

  The object of the present invention is to provide a torque detection device in which the above-mentioned disadvantageous associations of the detected torque with the rotational speed, volume flow, back pressure and other values are prevented.

  A first solution to the problem of the present invention is a torque detection device for a conical pulley winding transmission device, the torque detection device comprising an inclined surface fixedly coupled to the shaft of a conical pulley pair. A detection piston that is circumferentially engaged with the shaft and is slidable and rotatable in the axial direction relative to the shaft, and another inclined surface that is immovably coupled to the shaft. When the torque changes between the detection piston and the shaft, the axial position of the detection piston is changed by rolling along the inclined surfaces of a plurality of balls arranged between the inclined surfaces. The torque detection device further includes a guide surface that is fixedly coupled to the movable pulley, the sphere is in contact with a radially inner side of the guide surface, and the movable pulley is Coupled with the shaft so that it cannot rotate relative to the shaft and is slidable in the axial direction. And the hydraulic pressure related to the axial position of the detection piston is pressed toward a fixed pulley that is fixedly coupled to the shaft, and the guide surface is between the sphere and the axis of the shaft. Are formed such that the radial distance between them is related to the axial distance between the movable pulley and the fixed pulley, and the guide surface is in contact with the inclined surface of each sphere, the guide surface of the sphere, The contact point and the center point of the sphere are configured so as to be located in one plane oriented in the radial direction.

  Thereby, it is achieved that the centrifugal force is completely taken up by the reaction force, and an inconvenient rotational speed relationship of the pressure is not caused.

  Another solution to the problem of the present invention is a torque detection device for a conical pulley winding transmission device, the torque detection device being fixedly coupled to the shaft of a conical pulley pair; A circumferentially engaging surface of the shaft, having a detection piston that is slidable and rotatable in the axial direction relative to the shaft, and another inclined surface that is immovably coupled, and these inclined surfaces However, when the torque acting between the detection piston and the shaft changes, the axial position of the detection piston is changed by rolling along the inclined surfaces of a plurality of spheres arranged between the inclined surfaces. The torque detection device further includes a guide surface that is fixedly coupled to the movable pulley, and a radially outer region of the sphere is in contact with a radially inner side of the guide surface. Pulley is non-rotatable relative to the shaft and slides in the axial direction And is pressed against a fixed pulley that is immovably coupled to the shaft with a hydraulic pressure that is hydraulically related to the axial position of the detection piston. And the axial line between the shaft and the axis of the shaft are shaped so as to be related to the axial distance between the movable pulley and the fixed pulley, and the guide surface is in contact with the inclined surface of each sphere. The contact point and the contact point with the guide surface of the sphere are obtained by being configured to be located in one plane having a predetermined angle with respect to the radial direction.

  Thereby, the centrifugal force gives rise to a rotation speed relationship of the pressure-bonding pressure that can be defined in advance based on the angle, and this rotation speed relationship can be taken into account in the control of the transmission.

  Advantageously, the slope of the inclined surface decreases as it moves away from the lowest position of the inclined surface, and the pressure-bonding pressure and torque ratio is substantially independent of the relative position of the inclined surface and the guide surface.

  This can compensate for the negative effects of radial displacement of the contact point with respect to the center point of the sphere. This means that the radial deviation, axial deviation and circumferential deviation at each pre-defined position of the guide surface remain such that the ratio of torque and pressure or pressure in the second pressure chamber remains substantially constant. It is obtained by being arranged in.

  In the following, embodiments of the invention which can be used for almost any type of conical pulley wound transmission with an integrated torque sensor will be described in detail with reference to the drawings.

  The geometry according to the invention described below can be used in the transmission shown in FIG.

  FIG. 1 a shows a sphere 40 between the inclined surfaces 32, 38, which are alternately formed on the support ring 30 or the detection piston 36 in the circumferential direction.

FIG. 1 a shows a torque-free state in which the detection piston 36 is as close as possible to the support ring 30. In the state shown in FIG. 1 b, the inclined surface 38 formed on the detection piston 36 is displaced in the circumferential direction y relative to the inclined surface 32 of the support ring 30 based on the torque input by the input wheel 54. As a result, the sphere 40 rolls to some extent along both inclined surfaces and enlarges the distance between the support ring 30 and the detection piston 36. As can be seen, the line connecting the contact points B ₁ and B ₂ and the center point M of the sphere forms a predetermined angle with respect to the x direction (the axial direction of the input shaft 10). In order for one plane including the contact points B ₁ , B ₂ , the center point M of the sphere, and the contact point of the sphere with the guide surface 58 to keep facing the radial direction, the molding guide surface 58 is shown in FIG. 2 has the shape shown in FIG. 2 when viewed in a sectional view along the line II-II. In this case, only a half is shown in the circumferential direction starting from the lowest position of the inclined surface 32 of the support ring 30 as viewed in the radial direction. As can be perceiving, the guide surface has a flat portion 60 in the middle region, the sphere 40 is in the flat portion 60 are in contact at a position indicated by a point P ₁ in FIG. 2a.

FIG. 2b shows the contact between the sphere 40 and the guide surface 58 in the state shown in FIG. 1b, in which case the contact points P ₂ , P ₃ have moved sideways and the point B ₁ , M, B ₂ , P ₄ (intermediate between P ₂ and P ₃ ), the one plane remains facing in the radial direction.

Pumping state, i.e. in the state shown in FIG. 2c corresponding to significant sliding between the inclined surfaces 32, 38 in the circumferential direction, the contact point P ₅ is further moved in comparison with the effective contact point P ₄ in FIG. 2b Yes.

  The guide surface 58 may be aligned with the inclined surfaces 32 and 38 such that one plane including the contact point between the inclined surface of the sphere and the guide surface and the center of the sphere is located in the radial direction. Thereby, it is ensured that the centrifugal force acting on the sphere 40 with the increase in the rotational speed is completely taken up by the reaction force, and that an undesirable rotational speed relationship of the pressure bonding pressure does not occur. Further, the guide surface 58 may be configured such that a contact point between the inclined surface of the sphere and the guide surface defines one plane having a given angle in the radial direction. Thereby, the rotational speed relationship of the pressure pressure which can be prescribed | regulated previously which can be considered in the hydraulic pressure control of a conical pulley winding transmission is obtained.

  FIG. 3 shows an inclined surface having a shape different from that of FIG. 1. In this case, only the inclined surface 32 of the support ring 30 is shown. As can be seen, the gradient α of the inclined surface 32 changes in the circumferential direction y, and this gradient decreases as the distance from the lowest position increases. With this gradient decreasing in the circumferential direction, the negative effect of the radial displacement of the contact point with respect to the sphere center M is r · tan (α) (corresponding to torque) and pressure or pressure in the second pressure chamber 42. The radial deviation, the axial deviation, and the circumferential deviation at any predetermined position of the inclined surface 32 or the guide surface 58 are maintained so that the ratio of the inclination surface 32 and the guide surface 58 remains substantially constant even when r and / or α changes. Based on the changing, it can be compensated. r is the radial distance of the contact point B from the axis of the input shaft 10, and α = α (r) is the main inclined surface angle related to the radial distance, that is, the inclined surface of the sphere 40 shown in FIG. Is the slope at the lowest position.

FIGS. 1a and 1b are cross-sectional views taken along the II plane shown in FIG. 4 with respect to the relative positions of the inclined surfaces that differ in the circumferential direction. 2a to 2c are cross-sectional views taken along the II-II plane shown in FIG. 4, and in this case, the spheres are at different positions with respect to the guide surface in the circumferential direction. It is the figure which showed the inclined surface of the shape different from FIG. 1 similarly to FIG. It is the figure which showed across the partial area | region of the drive side of the conical pulley winding transmission of a well-known structure type.

Claims (3)

A torque detection device for a conical pulley winding transmission device, the torque detection device comprising an inclined surface (32) fixedly coupled to a shaft (10) of a conical pulley pair, and a circumferential surface on the shaft. A detecting piston (36) which engages and is axially slidable and rotatable relative to the shaft and has another inclined surface (38) which is fixedly coupled thereto, and these inclinations When the torque changes between the detection piston and the shaft, the axial position of the detection piston is changed by rolling along the inclined surfaces of the plurality of spheres (40) arranged between the inclined surfaces. The torque detector further includes a guide surface (58) fixedly coupled to the movable pulley (14), and the sphere contacts the radially inner side of the guide surface. The movable pulley is not rotatable relative to the shaft and the shaft The guide surface is pressed against a fixed pulley that is fixedly slidably coupled to the shaft and immovably coupled to the shaft with a hydraulic pressure related to the axial position of the detection piston. And the radial spacing between the shaft axis and the axis of the shaft is shaped to relate to the axial spacing between the movable pulley and the fixed pulley,
The guide surface (58) has a contact point with each inclined surface (32, 38) of each sphere (40), a contact point with the guide surface (58) of the sphere, and a center point of the sphere oriented in the radial direction. A torque detection device for a conical pulley-wound transmission device, wherein the torque detection device is configured to be located in one plane. A torque detection device for a conical pulley winding transmission device, the torque detection device comprising an inclined surface (32) fixedly coupled to a shaft (10) of a conical pulley pair, and a circumferential surface on the shaft. A detecting piston (36) which engages and is axially slidable and rotatable relative to the shaft and has another inclined surface (38) which is fixedly coupled thereto, and these inclinations When the torque changes between the detection piston and the shaft, the axial position of the detection piston is changed by rolling along the inclined surfaces of the plurality of spheres (40) arranged between the inclined surfaces. The torque detector further includes a guide surface (58) fixedly coupled to the movable pulley (14), and the sphere contacts the radially inner side of the guide surface. The movable pulley is not rotatable relative to the shaft and the shaft The molding guide is slidably coupled and is pressed toward a fixed pulley that is immovably coupled to the shaft with a hydraulic pressure pressure related to the axial position of the detection piston. The surface is shaped such that the radial spacing between the sphere and the axis of the shaft is related to the axial spacing between the movable pulley and the fixed pulley;
The guide surface (58) has a predetermined angle with respect to the radial direction between the contact point of each sphere (40) with the inclined surface (32, 38) and the contact point with the guide surface (58) of the sphere. A torque detection device for a conical pulley-wound transmission device, characterized in that the torque detection device is configured to be located in one plane having the same.   As the slopes of the inclined surfaces (32, 38) move away from the lowest positions of these inclined surfaces, the ratio of pressure to pressure is almost independent of the relative positions of the inclined surfaces and the guide surfaces (58). The torque detection device according to claim 1, wherein the torque detection device decreases so as to be.

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