JP6638448B2 - Auxiliary drive belt tension adjustment device - Google Patents

Description

  The present invention relates to an accessory driving belt tension adjusting device.

  2. Description of the Related Art In recent years, there has been an increasing demand for reducing the environmental load of automobiles, and there is a demand for stricter fuel economy regulations (reducing CO2 emissions). In response to such demands for environmental conservation and resource saving, the need for fuel-efficient items is increasing, and mounting of an idling stop mechanism and hybridization are progressing. In the internal combustion engine of automobiles, a belt drive system in which accessories such as a water pump, compressor, and radiator fan necessary to operate the main engine, air conditioner, etc. are mechanically connected and driven by an accessory belt. (Hereinafter referred to as “auxiliary drive system”) is common. In the accessory drive system, the driving force is transmitted via an accessory belt wound around a crank pulley as a main engine pulley and each accessory pulley. Also in this accessory drive system, the need for loss reduction is increasing.

  In the accessory drive system that transmits the driving force by the belt, it is necessary to apply tension to the belt so that slip does not occur between each pulley and the belt, so a tensioner for keeping the belt tension at a constant value is required. It is generally used. This tensioner has a function of maintaining a constant belt tension in a section where the tensioner is provided. The tension applied to the belt increases on the side pulled by the drive pulley (hereinafter, also referred to as “tension side”), and decreases on the side pushed out by the drive pulley (hereinafter, also referred to as “loose side”). For example, when an alternator is provided as an auxiliary machine, the crank pulley of the engine, which is the main engine pulley, becomes the drive pulley, and the alternator pulley, which is the auxiliary machine pulley, becomes the driven pulley.

  The tension required to drive the belt increases in proportion to the torque transmitted by the belt. That is, the appropriate value of the tension required to drive the belt changes depending on the load state of the driven pulley. Specifically, for example, the tension required to drive the belt changes according to the amount of power generated by the alternator. When the power generation of the alternator is large and the transmission torque is large, the rotation resistance of the auxiliary pulley connected to the rotor of the alternator increases, as compared with the case where the power generation of the alternator is small and the transmission torque is small. To obtain the torque, a larger tension is required than when obtaining a small transmission torque. For this reason, for example, even if the amount of power generated by the alternator is maximized and the rotational resistance of the auxiliary pulley of the alternator is maximized, the tensioner is designed to prevent slippage between the respective pulleys and the belt. It is set so that a tension corresponding to the maximum power generation amount of the alternator is obtained.

  Here, when the tensioner is provided on the tension side, even if the load on the driven pulley is maximized, the tension on the loose side where the tension on the belt is small causes slippage between each pulley and the belt. It is necessary to set a tension applied to the tension side of the belt (hereinafter, referred to as “tension side tension”) so that the tension does not occur. That is, when the load on the driven pulley is maximized, it is necessary to set, as the initial tension, the tension on the tension side such that the tension on the loose side is obtained such that no slippage occurs between each pulley and the belt. As described above, when the tensioner is provided on the tension side, it is necessary to set the tension on the tension side required at the maximum load of the driven pulley as the initial tension. Therefore, it is unnecessary when the load on the driven pulley is small and the transmission torque is small. A large tension is applied to the belt, and the transmission efficiency of the driving force by the belt decreases.

  On the other hand, when the tensioner is provided on the slack side, the initial tension of the tension applied to the slack side of the belt (hereinafter, referred to as “slack side tension”) may be set to the slack side tension required at the time of the maximum load of the driven pulley. . That is, when a tensioner is provided in the accessory drive system, the initial tension applied to the belt can be made smaller when the tensioner is provided on the loose side of the belt than when the tensioner is provided on the tight side of the belt. For this reason, the tensioner is preferably provided on the loose side of the belt.

  For example, Patent Literature 1 discloses a belt tension adjusting device that adjusts a tension applied to a belt by swinging an accessory according to an operation state of the accessories.

JP 2009-180177 A

  However, since the structure described in Patent Document 1 has a structure in which the accessory (motor generator) itself swings, there is a possibility that the wiring of the motor generator may be broken due to fatigue deterioration by repeating the swing. This can be a factor in reducing the reliability of the drive system.

  The present invention has been made in view of the above, and an object of the present invention is to provide an accessory driving belt tension adjusting device that can achieve both high reliability and loss reduction of an accessory driving system.

  In order to solve the above-described problems and achieve the object, an auxiliary device driving belt tension adjusting device applies tension to a slack side section of a belt that transmits driving force between a first pulley and a second pulley by hydraulic pressure. A belt tension adjusting mechanism for driving a roller, and a hydraulic supply mechanism for supplying hydraulic pressure to the belt tension adjusting mechanism via a hydraulic pipe, wherein the hydraulic supply mechanism is fixed to a shaft of the second pulley. A first housing, a second housing provided on a circumferentially outer side of the first housing, and supported so as to be rotatable in a circumferential direction with respect to the first housing; A hydraulic chamber whose volume decreases due to a circumferential phase difference generated by the changing rotational movement between the first housing and the second housing; and a hydraulic oil supplied from the hydraulic chamber, And oil passage for supplying the pressure pipe includes.

  According to the above configuration, a slack-side tension proportional to the transmission torque can be applied to the belt, and it is possible to reduce the loss of the accessory drive system.

  Further, in the above configuration, the hydraulic pressure supply mechanism is arranged such that the cam surfaces are axially opposed to each other with the rolling element interposed therebetween, and the first annular cam plate and the second annular cam plate are provided with an urging force in the axial direction by an elastic member. A cam plate, wherein the first cam plate is disposed so as to have a fixed circumferential position with respect to the first housing, and the second cam plate has a fixed circumferential position and an axial position with respect to the second housing. The hydraulic chamber is a space surrounded by the first housing, the second housing, and the first cam plate, and the oil flow path is formed from the hydraulic chamber to the first housing and the first housing. An opening may be formed at the rotation axis of the second pulley through a shaft of the second pulley, and the hydraulic pipe may be connected to the opening.

  As a desirable mode, the hydraulic chamber is provided between the first housing and the second housing, between the first housing and the first cam plate, and between the second housing and the first cam plate. Is preferably sealed by a seal member.

  With the above configuration, it is possible to provide a sealed structure in which hydraulic oil leaked from the hydraulic chamber to the belt tension adjusting mechanism does not escape.

  Further, in the above configuration, the hydraulic pressure supply mechanism is disposed so that the cam surfaces are opposed to each other in the axial direction with the rolling element interposed therebetween, and is axially moved by the elastic member via the annular member and the hydraulic oil in the hydraulic chamber. An annular first cam plate and a second cam plate to which an urging force is applied are included, and the first cam plate is arranged so that a circumferential position is fixed to the first housing, and the second cam plate is A circumferential position and an axial position are fixed and arranged with respect to the second housing, and the hydraulic chamber is surrounded by the first housing, the second housing, the annular member, and the first cam plate. A space, wherein the oil passage extends from the hydraulic chamber through the shafts of the first housing and the second pulley, and is opened at the rotation axis of the second pulley. It may be connected.

  As a desirable mode, the hydraulic chamber is provided between the first housing and the annular member, between the second housing and the annular member, and between the first housing and the first cam plate. Preferably, the space between the second housing and the first cam plate is sealed by a seal member.

  With the above configuration, it is possible to provide a sealed structure in which hydraulic oil leaked from the hydraulic chamber to the belt tension adjusting mechanism does not escape.

  In a preferred embodiment, a hydraulic booster is provided at an intermediate portion of the hydraulic pipe.

  With the above configuration, it is possible to obtain an accessory driving belt tension adjusting device having a wide range of application to the accessory driving system.

  According to the present invention, it is possible to provide an accessory driving belt tension adjusting device capable of achieving both high reliability and loss reduction of an accessory driving system.

FIG. 1 is a diagram illustrating an example of an accessory drive system. FIG. 2 is a conceptual diagram showing the relationship between the transmission torque of the drive pulley and the tension on the tight side and the loose side. FIG. 3 is a diagram illustrating a relationship between a transmission torque and a tension in an accessory drive system in which a belt is wound around two pulleys. FIG. 4 is a structural conceptual diagram of an accessory drive system to which the accessory drive belt tension adjusting device according to the first embodiment is applied. FIG. 5 is a schematic cross-sectional view of a hydraulic supply mechanism of the accessory drive belt tension adjusting device according to the first embodiment. FIG. 6 is a view of the first cam plate, the rolling element, and the second cam plate as viewed in the direction of arrow A shown in FIG. FIG. 7 is a view of the first cam plate, the rolling elements, and the second cam plate as viewed in the direction indicated by the arrow B shown in FIG. FIG. 8 is a diagram illustrating a state change of the hydraulic supply mechanism of the accessory driving belt tension adjusting device according to the first embodiment when the first pulley is generating a driving force. FIG. 9 is a diagram illustrating an operation example of the accessory drive belt tension adjusting device according to the first embodiment when the first pulley is generating a driving force. FIG. 10 is a schematic cross-sectional view of a hydraulic supply mechanism of the accessory drive belt tension adjusting device according to the second embodiment. FIG. 11 is a diagram illustrating a state change of the hydraulic supply mechanism of the accessory drive belt tension adjusting device according to the second embodiment when the first pulley is generating a driving force. FIG. 12 is a structural conceptual diagram of an accessory drive system to which the accessory drive belt tension adjusting device according to the third embodiment is applied.

  An embodiment (embodiment) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The components described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the components described below can be appropriately combined.

(Embodiment 1)
FIG. 1 is a diagram illustrating an example of an accessory drive system. The accessory drive system shown in FIG. 1 is, for example, an internal combustion engine of an automobile, which mechanically uses an accessory belt to drive accessories such as a water pump, a compressor, and a radiator fan necessary for operating an engine as a main engine, an air conditioner, and the like. This is a belt drive type accessory drive belt system that is connected and driven, and includes a crank pulley 101 provided on a crankshaft of an engine as a main engine, and accessory pulleys 201 to 201 provided on shafts of respective accessories. A belt 301 is wound around the belt 205, and a driving force is transmitted to each accessory via the belt 301.

  In the present embodiment, in the example shown in FIG. 1, when transmitting the driving force generated by the engine to each accessory, the crank pulley 101 of the engine is referred to as a drive pulley, and the accessory pulleys 201 to 201 of each accessory are used. 205 is called a driven pulley. Further, in an accessory drive system provided with a generator having a starter function (ISG: Integrated Starter Generator) as an accessory, when an ISG drive force is transmitted to perform engine start or drive assist, the ISG shaft is used. Is a driving pulley, and the crank pulley 101 is a driven pulley.

  FIG. 2 is a conceptual diagram showing the relationship between the transmission torque of the drive pulley and the tension on the tight side and the loose side. FIG. 3 is a diagram illustrating a relationship between a transmission torque and a tension in an accessory drive system in which a belt is wound around two pulleys. 2 and 3 show the relationship between the tension T1 and the tension T2 when the driving pulley 100 generates a driving force in the direction indicated by the arrow. FIG. 3 (a-1) shows an example in which the tensioner 400 is not provided on any of the tension side and the loose side, and FIG. 3 (a-2) shows that the tensioner 400 is provided on both the tension side and the loose side. 4 shows the relationship between the transmission torque and the tension in the case where no transmission is performed. FIG. 3 (b-1) shows an example in which the tensioner 400 is provided on the tension side, and FIG. 3 (b-2) shows the relationship between the transmission torque and the tension when the tensioner 400 is provided on the tension side. I have. FIG. 3C-1 shows an example in which the tensioner 400 is provided on the loose side, and FIG. 3C-2 shows the relationship between the transmission torque and the tension when the tensioner 400 is provided on the loose side. I have. Also, the dashed lines shown in FIGS. 3A-2 to 3C-2 show the ideal characteristics of the tension T1 and are shown in FIGS. 3A-2C. The dashed line indicates ideal characteristics of the loose side tension T2.

  As shown in FIG. 2, when the driving pulley 100 rotates in the direction of the arrow to generate a driving force, the transmission torque N transmitted by the belt is equal to the radius r of the driving pulley 100, the tension T1 on the loose side, It is expressed by the following equation using the tension T2.

  N = r × (T1-T2)

  As shown in the above equation, the transmission torque N is proportional to the tension difference T1-T2 between the tension T1 and the tension T2. That is, the driving force generated by the driving pulley 100 can be transmitted to the driven pulley by providing a tension difference T1-T2 necessary for transmitting torque without causing a slip in the accessory driving system.

  As shown in FIG. 3 (a-1), even when the tensioner 400 is not provided on either the tension side or the loose side, the initial tension T0 applied to the belt is appropriately adjusted as shown in FIG. 3 (a-2). , The maximum transmission torque Nmax in the accessory drive system can be obtained. Here, when the slack side tension T2 becomes equal to or less than the minimum value T2min of the slack side tension T2 for obtaining the maximum transmission torque Nmax, the belt 300 slips in the transmission torque region of the maximum transmission torque Nmax or less. . Therefore, when the maximum transmission torque Nmax to be achieved in the accessory drive system is generated, it is necessary to set the initial tension T0 so that the loose side tension T2 does not fall below the minimum value T2min. In the example shown in FIG. 3, when the maximum transmission torque Nmax is generated, the maximum value of the tension T1 when the looseness tension T2 becomes the minimum value T2min is set to T1max.

  As shown in FIG. 3 (b-1), when the tensioner 400 is provided on the tension side and it is attempted to achieve the maximum transmission torque Nmax by keeping the tension T1 constant, it is shown in FIG. 3 (b-2). Thus, the tensioner 400 needs to be set so that the initial tension T0 is equal to or greater than T1max. In this case, in the transmission torque region equal to or less than the maximum transmission torque Nmax, an excessively unnecessary tension is applied to the belt 300, and a large load is applied to the driving pulley 100 and the driven pulley 200, and the transmission efficiency of the driving force is reduced. descend.

  On the other hand, as shown in FIG. 3 (c-1), when the tensioner 400 is provided on the loose side and the maximum transmission torque Nmax is to be achieved by keeping the loose side tension T2 constant, FIG. As shown in -2), the tensioner 400 may be set so that the initial tension T0 is T2min or more. However, even when the tensioner 400 is provided on the loose side (see FIG. 3 (c-1)), it is necessary to always apply a tension of T2min or more to the loose side regardless of the magnitude of the transmission torque (FIG. 3 (c)). -2)). In an internal combustion engine of an automobile or the like, the loss in a low torque region such as when idling or running at high speed is reduced, and the loose side tension T2 approaches an ideal characteristic, that is, the loose side tension T2 proportional to the magnitude of the transmission torque. Is expected to further improve fuel efficiency.

  FIG. 4 is a structural conceptual diagram of an accessory drive system to which the accessory drive belt tension adjusting device according to the first embodiment is applied. In the accessory drive system shown in FIG. 4, a belt 3 that transmits a driving force between a first pulley 1 and a second pulley 2 is wound around the first pulley 1 and the second pulley 2. FIG. 4 shows an example of a structural concept in an initial state of the accessory drive system to which the accessory drive belt tension adjusting device according to the present embodiment is applied, that is, in a stopped state of the accessory drive system.

  In the accessory drive system shown in FIG. 4, the first pulley 1 is, for example, a crank pulley provided on a crankshaft of an engine which is an internal combustion engine of an automobile, and the second pulley 2 is provided on, for example, a shaft of an alternator. Alternator pulley. That is, in the accessory drive system shown in FIG. 4, the crank pulley that is the first pulley 1 is a driving pulley, and the alternator pulley that is the second pulley 2 is a driven pulley.

  As described above, in the accessory drive system, it is preferable to apply a slack-side tension proportional to the magnitude of the transmission torque. The auxiliary device driving belt tension adjusting device 10 according to the present embodiment is configured to be able to apply the slack side tension T2 to the belt 3 in proportion to the transmission torque. Hereinafter, the configuration of the accessory drive belt tension adjusting device 10 according to the present embodiment will be described with reference to FIGS. 4 and 5. In the following description, it is assumed that the belt 3 advances in the direction indicated by the arrow shown in FIG.

  As shown in FIG. 4, the auxiliary device driving belt tension adjusting device 10 according to the present embodiment applies tension to the slack side section of the belt 3 that transmits driving force between the first pulley 1 and the second pulley 2 by hydraulic pressure. And a hydraulic supply mechanism 4 for supplying hydraulic pressure to the belt tension adjusting mechanism 5 via a hydraulic pipe 51.

  The belt tension adjusting mechanism 5 has a so-called hydraulic cylinder type structure, and includes a cylinder 52, a piston 53 provided inside the cylinder 52, and a piston rod connecting the piston 53 and the rotation axis CX of the roller 12. And an elastic member 55 that applies a biasing force to the piston 53 in the direction in which the piston rod 54 extends.

  The elastic member 55 has a function of giving a minimum necessary initial tension T0 at the initial stage when transmission torque starts to be applied to the belt 3 via the roller 12 attached to the distal end portion of the piston rod 52. Or a solid member such as an elastic rubber.

  The space between the cylinder 52 and the piston 53 and the space between the cylinder 52 and the hydraulic pipe 51 are sealed with a sealing member such as an O-ring or a lip seal, and hydraulic oil supplied from the hydraulic pressure supply mechanism 4 leaks and the hydraulic pressure is reduced. Has a sealed structure that does not escape. The details of this sealing structure are omitted here.

  FIG. 5 is a schematic sectional view of the auxiliary device driving belt tension adjusting device according to the first embodiment. FIG. 6 is a view of the first cam plate, the rolling element, and the second cam plate as viewed in the direction of arrow A shown in FIG.

  As shown in FIG. 5, the hydraulic supply mechanism 4 of the accessory drive belt tension adjusting device 10 according to the present embodiment includes the components of the second pulley 2. Specifically, the hydraulic pressure supply mechanism 4 includes a first housing 41, a second housing 42, a hydraulic chamber 43, and an oil flow path 44.

  The first housing 41 is a cylindrical member fixed to the shaft 7 of the second pulley 2.

  The second housing 42 is a cylindrical member that is provided on the outer side in the circumferential direction of the first housing 41 via a bearing 81 and is rotatably supported with respect to the first housing 41. Note that the bearing 81 is configured by, for example, a ball bearing, but the present invention is not limited by the configuration or type of the bearing 81.

  The volume of the hydraulic chamber 43 is compressed by a circumferential phase difference between the first housing 41 and the second housing 42 that changes according to the torque applied to the second housing 42.

  The oil flow path 44 supplies the hydraulic oil supplied from the hydraulic chamber 43 to the hydraulic pipe 51.

  Further, the hydraulic pressure supply mechanism 4 includes a first cam plate 66 and a second cam plate 67.

  As shown in FIGS. 5 and 6, the first cam plate 66 and the second cam plate 67 are arranged so that the cam surfaces face each other in the axial direction with a plurality of roller-shaped or ball-shaped rolling elements 64 interposed therebetween. An annular member to which an elastic member 65 applies an urging force in the axial direction. The rolling elements 64 may have a structure in which, for example, a plurality of rolling elements 64 are supported by an annular rolling element support member. Further, in the example shown in FIG. 6, an example in which the four rolling elements 64 are arranged at positions shifted by 90 degrees in the circumferential direction is shown, but the number and the position of the rolling elements 64 are not limited thereto and three or more. Rolling elements 64 may be arranged at equal intervals in the circumferential direction. Further, the elastic member 65 is formed of, for example, an annular disc spring, but may be a plate spring or a coil spring, or may be a solid member such as elastic rubber. The present invention is not limited by the configuration, material, and shape of the elastic member 65.

  As shown in FIG. 5, the first cam plate 66 is arranged such that the movement in the axial direction is restricted by the elastic member 65 locked by the wheel stopper member 91 and the circumferential position of the first cam plate 66 is fixed to the first housing 41. Have been. In the example shown in FIG. 5, the structure for fixing the circumferential position of the first cam plate 66 to the first housing 41 is omitted, but the first cam plate 66 is fixed to the first housing 41. However, the present invention is not limited by the structure for fixing the circumferential position.

  As shown in FIG. 5, the second cam plate 67 is disposed with the circumferential position and the axial position fixed relative to the second housing 42. In the example shown in FIG. 5, the structure for fixing the circumferential position and the axial position of the second cam plate 67 with respect to the second housing 42 is omitted. The present invention is not limited by the structure for fixing the circumferential position and the axial position of the two cam plates 67.

  The hydraulic chamber 43 is surrounded by a first housing 41, a second housing 42, and a first cam plate 66. A space between the first housing 41 and the second housing 42 is sealed by a seal member 92, and the first housing 41 is closed. The space between the first housing 41 and the first cam plate 66 is sealed by a seal member 93, and the space between the second housing 42 and the first cam plate 66 is a space sealed by a seal member 94. The seal members 92, 93, 94 are composed of, for example, O-rings and lip seals. However, the configuration of these seal members 92, 93, 94 or the sealing structure of the hydraulic chamber 43 is not limited thereto. The present invention is not limited by these configurations and structures.

  The oil passage 44 penetrates from the hydraulic chamber 43 through the first housing 41 and the shaft 7 of the second pulley 2, and is opened at the axial end of the shaft 7 around the rotation axis AX of the second pulley 2. I have. The hydraulic pipe 51 is connected to the opening 45 of the oil flow path 44 via a bearing 82. Note that the bearing 82 is configured by, for example, a ball bearing, but the present invention is not limited by the configuration or type of the bearing 82.

  In the above-described configuration, the hydraulic oil is filled in the sealed structure surrounded by the hydraulic chamber 43, the oil flow path 44, the hydraulic pipe 51, the cylinder 52 and the piston 53, and the tension of the auxiliary device driving belt according to the present embodiment is obtained. The adjusting device 10 is configured.

  Next, an operation of the accessory driving belt tension adjusting device 10 according to the present embodiment configured as described above will be described with reference to FIGS. FIG. 7 is a view of the first cam plate, the rolling elements, and the second cam plate as viewed in the direction indicated by the arrow B shown in FIG. FIG. 7A illustrates an initial state in which the first pulley 1 does not generate a driving force, and FIG. 7B illustrates the first housing 41 when the first pulley 1 generates a driving force. The phase difference in the circumferential direction with the second housing 42 is shown. FIG. 8 is a diagram illustrating a state change of the hydraulic supply mechanism of the accessory driving belt tension adjusting device according to the first embodiment when the first pulley is generating a driving force. FIG. 9 is a diagram illustrating an operation example of the accessory drive belt tension adjusting device according to the first embodiment when the first pulley is generating a driving force.

  In the accessory drive belt tension adjusting device 10 according to the present embodiment, the hydraulic chamber 43 of the hydraulic supply mechanism 4 is configured to be connected to the first housing 41 and the second housing 42 that change according to the torque given to the second housing 42. The volume decreases due to the circumferential phase difference caused by the rotational movement between them.

  As described above, the first cam plate 66 and the second cam plate 67 are given an urging force in the axial direction by the elastic member 65. The first cam plate 66 and the second cam plate 67 periodically have different thicknesses in the circumferential direction. For this reason, when the first pulley 1 is not generating a driving force, the axial force of the first cam plate 66 and the rolling element are reduced by the reaction force given by the elastic member 65 as shown in FIG. The sum of the diameter of the second cam plate 64 and the thickness of the second cam plate 67 in the axial direction is the thinnest D1. At this time, the rolling element 64 is located at a position where the circumferential position C1 on the first cam plate 66 and the circumferential position C2 on the second cam plate 67 match in the example shown in FIG.

  When the first pulley 1 is generating a driving force, the torque applied to the second housing 42 generates a torque in which the first cam plate 66 and the second cam plate 67 are displaced in the circumferential direction. As shown in ()), the rolling element 64 moves between the first cam plate 66 and the second cam plate 67. At this time, the sum of the axial thickness of the first cam plate 66, the diameter of the rolling elements 64, and the axial thickness of the second cam plate 67 increases, and a thrust is generated in the axial direction. The first housing 41 in which the first cam plate 66 is fixed in the circumferential direction and the second housing 42 in which the second cam plate 67 is fixed in the circumferential direction so that the thrust and the reaction force of the elastic member 65 are balanced. Between the circumferential position C1 on the first cam plate 66 and the circumferential position C2 on the second cam plate 67, a phase difference Δθ is generated. At this time, the total D2 of the axial thickness of the first cam plate 66, the diameter of the rolling element 64, and the axial thickness of the second cam plate 67 is, as shown in FIG. Due to the deformation, the first pulley 1 becomes thicker by ΔD than when no driving force is generated (D2 = D1 + ΔD). As a result, as shown in FIG. 8, the axial end of the first cam plate 66 moves in the axial direction by ΔD from the position D shown in FIGS. 5 and 8, and the volume of the hydraulic chamber 43 is accordingly reduced. Decrease. As a result, the hydraulic oil in the hydraulic chamber 43 flows into the oil flow path 44, and the hydraulic pressure is supplied to the belt tension adjusting mechanism 5 via the hydraulic pipe 51. At this time, as shown in FIG. 9, the piston 53 moves in the direction in which the piston rod 54 extends, and the roller 12 provided at the distal end of the piston rod 54 pushes the loose side of the belt 3 to apply tension.

  In the present embodiment, a torque applied to the second housing 42, a phase difference in the circumferential direction between the first housing 41 and the second housing 42 that changes according to the torque, and a hydraulic chamber that changes due to the phase difference 43, the amount of hydraulic fluid flowing into the belt tension adjusting mechanism 5 by the reduced volume of the hydraulic chamber 43, the hydraulic pressure supplied to the belt tension adjusting mechanism 5, and the movement by the hydraulic pressure. The moving amounts of the piston 53, the piston rod 54, and the roller 12 are proportional to each other. That is, in the auxiliary device driving belt tension adjusting device 10 according to the present embodiment, the loosening side tension T2 proportional to the transmission torque can be applied to the belt 3 with the above-described configuration.

  In addition, since the accessory drive belt tension adjusting device 10 according to the present embodiment does not have a structure for swinging the accessories such as the alternator, there is no factor that the wires of the accessories are disconnected due to fatigue deterioration. Thus, it is possible to realize the auxiliary device driving belt tension adjusting device 10 having high reliability.

  As described above, the auxiliary device driving belt tension adjusting device 10 according to the first embodiment applies tension to the slack side section of the belt 3 that transmits driving force between the first pulley 1 and the second pulley 2 by hydraulic pressure. A belt tension adjusting mechanism 5 for driving the roller 12 to be applied, and a hydraulic supply mechanism 4 for supplying a hydraulic pressure to the belt tension adjusting mechanism 5 via a hydraulic pipe 51 are provided.

  The hydraulic pressure supply mechanism 4 is provided on the first housing 41 fixed to the shaft 7 of the second pulley 2, and is provided on the outer side in the circumferential direction of the first housing 41, and is supported to be rotatable in the circumferential direction with respect to the first housing 41. The volume is reduced by the circumferential phase difference generated by the rotational movement between the first housing 41 and the second housing 42 which changes according to the torque given to the second housing 42 and the second housing 42. And a hydraulic passage 44 for supplying hydraulic oil supplied from the hydraulic chamber 43 to the hydraulic piping 51.

  In this configuration, the hydraulic supply mechanism 4 is provided with an annular first cam plate 66 and an annular first cam plate 66 which are arranged with their cam surfaces axially opposed to each other with the rolling element 64 interposed therebetween and which are biased in the axial direction by the elastic member 65. The first cam plate 66 is fixed to the first housing 41 in the circumferential direction, and the second cam plate 67 is positioned in the circumferential position and the axial position with respect to the second housing 42. Are fixed, the hydraulic chamber 43 is a space surrounded by the first housing 41, the second housing 42, and the first cam plate 66, and the oil flow path 44 is separated from the hydraulic chamber 43 by the first housing 41 and the second housing 41. An opening is formed in the rotation axis AX of the second pulley 2 through the shaft 7 of the pulley 2, and a hydraulic pipe 51 is connected to the opening 45, so that the loosening-side tension T2 proportional to the transmission torque is applied to the belt 3. Can be It is possible to reduce the loss of the driving system.

  Further, in the accessory drive belt tension adjusting device 10 according to the first embodiment, the hydraulic chamber 43 seals a space between the first housing 41 and the second housing 42 with a seal member 92, and the first housing 41 and the first cam 41. The space between the second housing 42 and the first cam plate 66 is sealed with a seal member 94. This makes it possible to provide a sealed structure in which hydraulic oil in the hydraulic chamber 43 leaks and hydraulic pressure applied to the belt tension adjusting mechanism 5 does not escape.

  In addition, in the accessory drive belt tension adjusting device 10 according to the present embodiment, there is no factor that the wires of the accessories are disconnected due to fatigue deterioration, and the highly reliable accessory drive belt tension adjuster 10 can be realized. .

  Thus, by applying the accessory drive belt tension adjusting device 10 according to the present embodiment to the accessory drive system, it is possible to achieve both high reliability and loss reduction of the accessory drive system.

(Embodiment 2)
FIG. 10 is a schematic cross-sectional view of the auxiliary device driving belt tension adjusting device according to the second embodiment. Note that the same components as those in the above-described first embodiment are denoted by the same reference numerals, and redundant description will be omitted.

  In the accessory drive belt tension adjusting device 10a according to the present embodiment, in the hydraulic supply mechanism 4a, the annular member 68 and the hydraulic chamber 43a are provided with respect to the first cam plate 66 and the second cam plate 67, as shown in FIG. The elastic member 65a applies a biasing force in the axial direction via the internal working oil. The elastic member 65a is formed of, for example, an annular disc spring in the same manner as the elastic member 65 of the first embodiment, but may be a plate spring or a coil spring, or may be a solid member such as elastic rubber. There may be. The present invention is not limited by the configuration, material, and shape of the elastic member 65a.

  In the present embodiment, as shown in FIG. 10, the movement of the first cam plate 66 in the axial direction is restricted by the elastic member 65a arranged via the annular member 68 and the hydraulic oil in the hydraulic chamber 43a. At the same time, the circumferential position is fixed to the first housing 41. In the example shown in FIG. 10, the structure for fixing the circumferential position of the first cam plate 66 with respect to the first housing 41 is omitted as in the first embodiment. On the other hand, the present invention is not limited by the structure in which the circumferential position of the first cam plate 66 is fixed.

  The hydraulic chamber 43 a is surrounded by the first housing 41, the second housing 42, the annular member 68, and the first cam plate 66, and the space between the first housing 41 and the first cam plate 66 is formed by a seal member 93. The space between the second housing 42 and the first cam plate 66 is sealed by a seal member 94, the space between the first housing 41 and the annular member 68 is sealed by a seal member 95, and the second housing 42 and the circle are sealed. The space between the ring member 68 is a space sealed by the seal member 96. The seal members 93, 94, 95, and 96 are composed of, for example, O-rings and lip seals, but the structure of these seal members 93, 94, 95, and 96 or the sealing structure of the hydraulic chamber 43a is not limited thereto. However, the present invention is not limited by these configurations and structures.

  In the first embodiment, when the first pulley 1 is generating a driving force, the volume of the hydraulic chamber 43 is reduced by the elastic member 65 being deformed in the axial direction. The configuration in which the hydraulic pressure is supplied to the belt tension adjusting mechanism 5 through the hydraulic pipe 51 by flowing into the flow path 44 has been described. In this case, the spring constant of the elastic member 65 is changed by the torque applied to the second housing 42. It is necessary to set an optimal value for the size of. In other words, it is necessary to optimize the spring constant of the elastic member 65 with respect to the urging force applied to the first cam plate 66 and the second cam plate 67 in the axial direction. That is, it is necessary to set the spring constant according to the tension applied to the belt 3 by the roller 12.

  On the other hand, in the accessory drive belt tension adjusting device 10a according to the present embodiment, as described above, the hydraulic oil in the annular member 68 and the hydraulic chamber 43a is applied to the first cam plate 66 and the second cam plate 67. , A biasing force is applied in the axial direction by the elastic member 65a. As a result, the first pulley 1 generates a driving force, and a torque is generated in which the first cam plate 66 and the second cam plate 67 are shifted in the circumferential direction, and the axial thickness of the first cam plate 66 and the rolling elements 64 are generated. Even if the sum of the diameter of the second cam plate 67 and the thickness in the axial direction of the second cam plate 67 is displaced, the elastic member 65a is hardly deformed in the axial direction. That is, the spring constant of the elastic member 65a may be set to a sufficiently large value with respect to the urging force applied to the first cam plate 66 and the second cam plate 67 in the axial direction.

  Next, an operation of the accessory drive belt tension adjusting device 10a according to the present embodiment configured as described above will be described with reference to FIGS. FIG. 11 is a diagram illustrating a state change of the hydraulic supply mechanism of the accessory drive belt tension adjusting device according to the second embodiment when the first pulley is generating a driving force.

  In the accessory drive belt tension adjusting device 10a according to the present embodiment, the hydraulic chamber 43a of the hydraulic pressure supply mechanism 4a has a first hydraulic chamber 43a that changes according to the torque applied to the second housing 42, as in the configuration of the first embodiment. The volume decreases due to a phase difference in the circumferential direction caused by the rotational movement between the housing 41 and the second housing 42.

  When the first pulley 1 does not generate a driving force, the axial force of the first cam plate 66 and the diameter of the rolling element 64 are caused by the reaction force given by the elastic member 65a, as shown in FIG. And the thickness of the second cam plate 67 in the axial direction is the thinnest D1. At this time, the rolling element 64 is located at a position where the circumferential position C1 on the first cam plate 66 and the circumferential position C2 on the second cam plate 67 match in the example shown in FIG.

  When the first pulley 1 is generating a driving force, the torque applied to the second housing 42 generates a torque in which the first cam plate 66 and the second cam plate 67 are displaced in the circumferential direction. As shown in ()), the rolling element 64 moves between the first cam plate 66 and the second cam plate 67. At this time, the sum of the axial thickness of the first cam plate 66, the diameter of the rolling elements 64, and the axial thickness of the second cam plate 67 increases, and a thrust is generated in the axial direction. The first housing 41 in which the first cam plate 66 is fixed in the circumferential direction and the second housing 42 in which the second cam plate 67 is fixed in the circumferential direction so that the thrust and the reaction force of the elastic member 65a are balanced. Between the circumferential position C1 on the first cam plate 66 and the circumferential position C2 on the second cam plate 67, a phase difference Δθ is generated. At this time, the sum D2 of the axial thickness of the first cam plate 66, the diameter of the rolling element 64, and the axial thickness of the second cam plate 67 is larger than when the first pulley 1 does not generate a driving force. Also increases by ΔD (D2 = D1 + ΔD). As a result, as shown in FIG. 11, the axial end of the first cam plate 66 moves in the axial direction by ΔD from the position D shown in FIGS. 10 and 11, and the volume of the hydraulic chamber 43a is accordingly reduced. Decrease. As a result, the hydraulic oil inside the hydraulic chamber 43 a flows into the oil flow path 44, and the hydraulic pressure is supplied to the belt tension adjusting mechanism 5 via the hydraulic pipe 51. At this time, as shown in FIG. 9, the piston 53 moves in the direction in which the piston rod 54 extends, and the roller 12 provided at the distal end of the piston rod 54 pushes the loose side of the belt 3 to apply tension.

  In the present embodiment, as described above, the spring constant of the elastic member 65a is set to a sufficiently large value with respect to the urging force applied to the first cam plate 66 and the second cam plate 67 in the axial direction. Accordingly, when the sum of the axial thickness of the first cam plate 66, the diameter of the rolling elements 64, and the axial thickness of the second cam plate 67 is displaced, the amount of deformation of the elastic member 65a in the axial direction is reduced. be able to. For this reason, similarly to the first embodiment, the torque given to the second housing 42 and the circumferential position generated by the rotational movement between the first housing 41 and the second housing 42 which changes according to this torque. The phase difference, the decrease in the volume of the hydraulic chamber 43a that changes due to the phase difference, the amount of hydraulic oil flowing into the belt tension adjustment mechanism 5 by the decrease in the volume of the hydraulic chamber 43a, and thereby the belt tension adjustment mechanism 5 , And the proportional relationship between the movement amount of the piston 53, the piston rod 54, and the roller 12 moved by the oil pressure is maintained. That is, in the auxiliary device driving belt tension adjusting device 10a according to the present embodiment, the loosening side tension T2 proportional to the transmission torque is applied to the belt 3 as in the first embodiment, by adopting the above-described configuration. It becomes possible.

  Also, since the accessory drive belt tension adjusting device 10a according to the present embodiment does not have a structure for swinging the accessories such as the alternator, there is no factor that the wires of the accessories are disconnected due to fatigue deterioration. Therefore, a highly reliable auxiliary device driving belt tension adjusting device 10a can be realized.

  As described above, the auxiliary device driving belt tension adjusting device 10a according to the second embodiment provides the first cam plate 66 and the second cam plate 67 via the annular member 68 and the hydraulic oil in the hydraulic chamber 43a. Thus, the elastic member 65a applies a biasing force in the axial direction. For this reason, it is not necessary to optimize the spring constant of the elastic member 65a with respect to the urging force applied to the first cam plate 66 and the second cam plate 67 in the axial direction. The belt tension adjusting device 10a can be realized.

  Further, by setting the spring constant of the elastic member 65a to a sufficiently large value with respect to the urging force applied to the first cam plate 66 and the second cam plate 67 in the axial direction, the thickness of the first cam plate 66 in the axial direction can be reduced. When the sum of the diameter of the rolling element 64 and the axial thickness of the second cam plate 67 is displaced, the amount of axial deformation of the elastic member 65a can be reduced. Therefore, similarly to the first embodiment, the slack-side tension T2 proportional to the transmission torque can be applied to the belt 3, and the loss of the accessory drive system can be reduced.

  In the accessory drive belt tension adjusting device 10a according to the second embodiment, the hydraulic chamber 43a seals the space between the first housing 41 and the first cam plate 66 with a seal member 93, and the second housing 42 and the first The space between the first housing 41 and the annular member 68 is sealed with a seal member 95, and the space between the second housing 42 and the annular member 68 is sealed with a seal member 96. And sealed. This makes it possible to provide a sealed structure in which the hydraulic oil in the hydraulic chamber 43a leaks and the hydraulic pressure applied to the belt tension adjusting mechanism 5 does not escape.

  In addition, in the accessory driving belt tension adjusting device 10a according to the present embodiment, similarly to the first embodiment, there is no factor that the wires of the accessories are disconnected due to fatigue deterioration, and the accessory driving belt tension adjusting device with high reliability is provided. The device 10a can be realized.

  As described above, by applying the accessory drive belt tension adjusting device 10a according to the present embodiment to the accessory drive system, it is possible to achieve both high reliability and loss reduction of the accessory drive system.

(Embodiment 3)
FIG. 12 is a structural conceptual diagram of an accessory drive system to which the accessory drive belt tension adjusting device according to the third embodiment is applied. The same components as those in the first and second embodiments described above are denoted by the same reference numerals, and redundant description will be omitted.

  The accessory drive belt tension adjusting device 10b according to the third embodiment includes a hydraulic booster 8 at an intermediate portion between the hydraulic piping 51a and the hydraulic piping 51b between the hydraulic supply mechanism 4 and the belt tension adjusting mechanism 5. It has a configuration. Thus, the hydraulic pressure supplied from the hydraulic pressure supply mechanism 4 can be amplified and supplied to the belt tension adjusting mechanism 5. For this reason, for example, when the amount of change in the volume of the hydraulic chambers 43, 43a in the hydraulic supply mechanisms 4, 4a is small, sufficient hydraulic pressure cannot be supplied to the belt tension adjusting mechanism 5, or the first pulley 1 generates a driving force. Also, the present invention can be applied to a case where a sufficient phase difference in the circumferential direction between the first cam plate 66 and the second cam plate 67 caused by the torque applied to the second housing 42 cannot be obtained. That is, the range of application to the accessory drive system can be expanded.

  As described above, the auxiliary device driving belt tension adjusting device 10b according to the third embodiment is configured such that the hydraulic pressure is supplied to the intermediate portion between the hydraulic piping 51a and the hydraulic piping 51b between the hydraulic supply mechanisms 4, 4a and the belt tension adjusting mechanism 5. With the configuration provided with the booster 8 of, an accessory drive belt tension adjusting device 10b having a wide application range to the accessory drive system can be obtained.

  As described above, by using the accessory drive belt tension adjusting devices 10, 10a, and 10b according to the embodiment, a loose side tension proportional to the transmission torque can be applied to the belt. The devices 10, 10a, and 10b are suitable for achieving both high reliability and loss reduction of the accessory drive system.

DESCRIPTION OF SYMBOLS 1 1st pulley 2 2nd pulley 3 Belt 4, 4a Hydraulic supply mechanism 5 Belt tension adjustment mechanism 7 Shaft (2nd pulley)
8 Booster device 10, 10a, 10b Auxiliary device drive belt tension adjusting device 12 Roller 41 First housing 42 Second housing 43, 43a Hydraulic chamber 44 Oil flow passage 45 Opening 65, 65a Elastic member 66 First cam plate 67 First 2 cam plate 68 Ring member 81, 82 Bearing 91 Wheel stopper 92, 93, 94, 95, 96 Seal member 100 Driving pulley 200 Follower pulley 201-205 Auxiliary pulley 301 Belt 400 Tensioner AX Rotation axis (second pulley) )
CX rotating shaft (roller)
T0 Initial tension T1 Tension tension T2 Loose tension

Claims (6)

A belt tension adjusting mechanism that drives a roller that applies tension to a slack-side section of the belt that transmits a driving force between the first pulley and the second pulley by hydraulic pressure;
A hydraulic supply mechanism for supplying hydraulic pressure to the belt tension adjusting mechanism via hydraulic piping,
With
The hydraulic supply mechanism includes:
A first housing fixed to a shaft of the second pulley;
A second housing provided on a circumferentially outer side of the first housing and supported so as to be rotatable in a circumferential direction with respect to the first housing;
A hydraulic chamber whose volume is reduced by a circumferential phase difference caused by a rotational movement between the first housing and the second housing that changes according to a torque applied to the second housing;
An oil flow path for supplying hydraulic oil supplied from the hydraulic chamber to the hydraulic pipe,
Containing
Auxiliary drive belt tension adjustment device. The hydraulic supply mechanism includes:
An annular first cam plate and a second cam plate, each of which has a cam surface axially opposed to the rolling element and is provided with an urging force in the axial direction by an elastic member,
The first cam plate is disposed so that a circumferential position is fixed to the first housing,
The second cam plate is disposed so that a circumferential position and an axial position are fixed with respect to the second housing,
The hydraulic chamber is a space surrounded by the first housing, the second housing, and the first cam plate,
The oil passage extends from the hydraulic chamber through the shafts of the first housing and the second pulley, and is opened at the rotation axis of the second pulley, and the opening is connected to the hydraulic pipe. ,
The auxiliary device driving belt tension adjusting device according to claim 1. The hydraulic chamber is
A seal member seals between the first housing and the second housing, between the first housing and the first cam plate, and between the second housing and the first cam plate. ing,
The accessory drive belt tension adjusting device according to claim 2. The hydraulic supply mechanism includes:
An annular first cam plate which is arranged so that the cam surfaces are opposed to each other in the axial direction with the rolling element interposed therebetween, and is provided with an urging force in the axial direction by an elastic member via the annular member and the hydraulic oil in the hydraulic chamber. And a second cam plate,
The first cam plate is disposed so that a circumferential position is fixed to the first housing,
The second cam plate is disposed so that a circumferential position and an axial position are fixed with respect to the second housing,
The hydraulic chamber is a space surrounded by the first housing, the second housing, the annular member, and the first cam plate,
The oil passage extends from the hydraulic chamber through the shafts of the first housing and the second pulley, and is opened at the rotation axis of the second pulley, and the opening is connected to the hydraulic pipe. ,
The auxiliary device driving belt tension adjusting device according to claim 1. The hydraulic chamber is
Between the first housing and the annular member, between the second housing and the annular member, between the first housing and the first cam plate, and between the second housing and the first The space between the cam plate and the cam plate is sealed by a seal member.
The auxiliary device driving belt tension adjusting device according to claim 4.   The auxiliary device drive belt tension adjusting device according to claim 1, wherein a hydraulic booster is provided at an intermediate portion of the hydraulic pipe.

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