JP4648762B2 - Transmission belt pulley, belt transmission, and engine accessory drive system - Google Patents

Description

  The present invention relates to a transmission belt pulley, a belt transmission device, and an engine accessory drive system.

  In a transmission device using a flat belt, the flat belt may meander while the vehicle travels, or may travel offset by moving toward one side of the pulley. This is because the flat belt is more sensitive to changes in the components of the transmission device, such as the displacement of the pulley shaft from its normal position, the deflection of the pulley shaft due to changes in shaft load, and the vibration of the pulley, compared to other transmission belts. It is. When such meandering / offset running occurs, the flat belt comes into contact with the flange of the flat pulley, causing fuzz on the side surface of the flat belt and fraying of the core.

  In order to solve this problem, it is known to attach a crown to the outer peripheral surface of the flat pulley (form a medium-high curved surface). There is also a proposal that the crown on the outer peripheral surface of the pulley is formed in a spherical shape centered on the rotation center of the pulley (see Patent Document 1). This is because when there is a tension difference between the left and right sides of the flat belt and the pulley shaft is tilted, and the flat belt is offset on the pulley, a rotational moment acts on the pulley due to the tension of the flat belt. By utilizing this, the inclination of the pulley shaft and the deviation of the flat belt are eliminated.

  Moreover, what formed many groove | channels in the outer peripheral surface of the flat pulley at intervals in the circumferential direction is known (refer patent document 2). In other words, the groove extends symmetrically from the center of the width of the pulley so as to form a “<” shape on both sides, and a frictional force that moves the flat belt to the center between the flat belt and the pulley. By generating the belt, meandering or deviation of the belt is prevented.

Furthermore, it is also known that guide rollers are arranged on both sides of the flat belt to restrict the travel position of the flat belt (see Patent Document 3).
Japanese Utility Model Publication No.59-45351 JP-A-6-307521 Japanese Utility Model Publication No. 63-6520

  However, when the crown is formed on the pulley, if the radius of curvature of the crown is reduced with an emphasis on the running stability of the flat belt (preventing meandering and shifting), the stress concentrates in the center of the belt width, and the belt width The whole cannot be used effectively for transmission, leading to early fatigue of the core and a reduction in transmission capability.

  Further, when the pulley crown is formed in a spherical shape centered on the rotation center of the pulley, even if the effect of preventing the transmission belt from shifting is enhanced, stress is concentrated at the center of the belt width by the pulley crown. Still remains.

  If the flat pulley is grooved as described above, the manufacturing cost of the flat pulley increases, and it is difficult to reliably prevent meandering and shifting of the flat belt only by the groove processing.

  Furthermore, if a method of restricting the running position by arranging guide rollers or the like on both sides of the flat belt, both sides of the flat belt will always come into contact with such a restricting member. Line fraying is likely to occur. Therefore, it is necessary to specially process the flat belt for preventing them, which is disadvantageous in reducing the production cost of the flat belt.

  For these reasons, flat belt transmissions are not fully utilized despite the fact that they have less loss due to belt bending and very high transmission efficiency compared to other belts such as V-belts. It is.

  Therefore, the present invention can surely prevent the meandering and shifting of the flat belt and other transmission belts, so that the belt transmission device can be effectively used for various industrial machines and other devices. To do.

  The present invention displaces the pulley by utilizing the fact that the position of the axial load applied to the pulley shaft is changed by the tension of the transmission belt when the transmission belt is offset, and the transmission belt is offset and meandered. To prevent.

  Furthermore, the present invention utilizes a mechanism that prevents the transmission belt from running or meandering, and moves the transmission belt following the pulley by moving the pulley in the pulley axial direction, thereby driving the belt. The position can be changed.

  That is, the pulley for a transmission belt of the present invention includes a pulley body around which the transmission belt is wound, and a support means for supporting the pulley body so as to be rotatable about a pulley axis and swingable about a predetermined pivot axis, The pivot is tilted at a predetermined tilt angle forward of the pulley body in the rotational direction with respect to the axial load direction when viewed along the pulley axis direction, and the support means is configured to cause the pulley body to pivot on the pivot axis. At the same time, it can be reciprocated in the pulley shaft direction.

  According to this transmission belt pulley, when the pulley body is stationary with respect to the pulley axial direction, the transmission belt is offset on the pulley body, and the axial load is shifted from the pivot position to one side in the pulley body width direction. When this happens, the axial load causes a rotational moment about the pivot axis to act on the pulley body, and the pulley body rotates and displaces around the pivot axis.

  At this time, as will be described in detail later, the pivot shaft is tilted at a predetermined tilt angle forward of the pulley body in the rotation direction with respect to the axial load direction when viewed along the pulley shaft direction. Is 90 degrees, the pulley body is inclined so that the side opposite to the side where the transmission belt is offset is higher, and when the tilt angle is more than 0 degree and less than 90 degrees, the pulley body In addition to inclining, the side where the transmission belt is offset becomes a diagonal state with the front side in the belt running direction.

  Due to the inclination and / or crossing of the pulley main body, a force for returning the offset from the pulley main body to the transmission belt acts. Therefore, the transmission belt travels at a position where the return force and the offset force are balanced.

  Thus, when the pulley body is stationary with respect to the pulley axial direction, the transmission belt pulley causes the transmission belt to travel at a position where the return force and the offset force are balanced. When the pulley body and the pivot are moved in the pulley axis direction, the transmission belt is relatively displaced in the width direction on the pulley body, and the axial load is shifted from the pivot position to one side in the pulley body width direction. It comes to act on a shaft member. Due to the axial load, as described above, the pulley main body is rotationally displaced about the pivot, and a force is applied to return the offset from the pulley main body to the transmission belt. Therefore, if the movement of the pulley body in the axial direction is continued, a return force continues to act on the transmission belt, and the transmission belt moves in the pulley axis direction following the movement of the pulley body. To do. As a result, the running position of the belt is changed. As described above, the transmission belt pulley moves the transmission belt by a return force acting from the pulley body, and for example, does not forcibly move the traveling position of the transmission belt by hitting the flange. The pulley body does not require a flange. In other words, there is no decrease in belt life due to flange contact.

  Accordingly, the transmission belt pulley can change the traveling position of the transmission belt by moving the pulley body while preventing the transmission belt from moving in a stationary state, for example, a clutch mechanism, a transmission mechanism, and the like. Etc., and can be used for various belt transmission devices.

  It is preferable that the tilt angle of the pivot is set in an angle range exceeding 0 degree and not exceeding 90 degrees.

  When the tilt angle is 90 degrees, that is, when the pivot is orthogonal to the axial load direction, the pulley body is rotationally displaced so that the side on which the transmission belt is offset moves in the axial load direction. . In other words, when the height is seen in the axial load direction, the transmission belt is inclined such that the side from which the transmission belt is offset is low and the opposite side is high. In other words, the outer peripheral surface of the pulley body is inclined in the same manner as the crown. As a result, a return force in a direction opposite to the offset direction is applied to the transmission belt.

  When the tilt angle is less than 90 degrees, the rotational displacement of the pulley body when the transmission belt is deviated includes not only the component in the axial load direction but also the longitudinal direction (described above) The component in the direction in which the transmission belt is running in contact with the pulley body is added. That is, the pulley body is not only inclined in the axial load direction but also in contact with the transmission belt in an oblique manner.

  Then, since the pivot is tilted forward in the rotational direction of the pulley body with respect to the axial load direction, when the transmission belt is offset, the pulley body is driven on the side where the transmission belt is offset. It becomes the diagonal state which became the front side of the direction. By rotating the pulley body in an oblique state, a force is applied to the transmission belt in a direction for returning the offset from the pulley body.

  Eventually, when the tilt angle is greater than 0 degree and less than 90 degrees, when the transmission belt is displaced, the pulley body causes a difference in height in the axial load direction in the pulley for the transmission belt. Both the return force caused by the inclination of the pulley and the return force caused by the pulley body being inclined with respect to the transmission belt act.

  Of the return force due to the inclination and the return force due to the crossing, the latter is more effective in preventing the deviation.

  Therefore, it is preferable that the tilt angle is more than 0 degree and less than 90 degrees. More preferably, in order to effectively use the return force due to the oblique crossing, the tilt angle is set to more than 0 degree and not more than 45 degrees. On the other hand, when the tilt angle is close to 0 degrees, it becomes difficult to generate a rotational moment about the above-mentioned pivot axis. Therefore, it is more preferable that the tilt angle is 5 degrees or more and 45 degrees or less, or 10 degrees or more and 30 degrees or less.

  Thus, by making the tilt angle more than 0 degree and less than 90 degrees, the meandering control of the transmission belt can be effectively performed is equivalent to the fact that the traveling position of the transmission belt can also be effectively switched. is there.

  The support means is preferably configured to position the pulley body at two or more belt travel positions aligned in the pulley axial direction.

  According to this configuration, when the pulley body is positioned at two or more belt travel positions, the transmission belt travels at two or more travel positions. Therefore, it is advantageous when used for various belt transmission devices including a clutch mechanism, a transmission mechanism, and the like.

  The support means is provided integrally with the pulley main body, and is a cylindrical shaft member that rotatably supports the pulley main body around the pulley shaft, and is inserted into the cylindrical shaft member, and the pulley A support rod extending coaxially with the shaft, a pin disposed near the center of the width of the pulley body and constituting the pivot shaft, and interposed between the shaft member and the support rod so that the shaft member is disposed around the pin An intermediate member that swingably supports and reciprocates along the support rod together with the pin, and a power source that generates power for reciprocating the intermediate member may be included.

  According to this configuration, when the intermediate member is moved along the support rod by the power generated by the power source, the pin and the shaft member are moved in the pulley shaft direction together with the intermediate member. Along with this, the transmission belt is relatively displaced in the width direction on the pulley body, the pulley body is rotationally displaced around the pin, and a force is applied to return the displacement from the pulley body to the transmission belt. Then, the transmission belt follows the movement of the pulley body and moves in the pulley axial direction.

  As the power source, various power sources such as a vacuum cylinder, a motor, a linear motor, a solenoid, and a hydraulic cylinder can be adopted.

A belt transmission device according to the present invention includes the transmission belt pulley, a driving pulley, a driven pulley, and a transmission belt wound between the driving pulley and the driven pulley, and the transmission belt. The pulley is pressed so as to apply tension to the transmission belt.

  Therefore, in a state where the pulley main body is stationary with respect to the pulley axial direction, the transmission belt can be prevented from meandering and shifting while applying a stable tension to the transmission belt, and the transmission capability of the transmission belt can be reduced. It will be advantageous for full use.

  On the other hand, since the traveling position of the transmission belt can be switched by moving the pulley body in the pulley axial direction, the belt transmission device can be a device including a speed change mechanism and a clutch mechanism.

  Here, any one of the driving pulley and the driven pulley includes a first pulley and a second pulley that are arranged in parallel in the rotation axis direction and have substantially the same outer peripheral surface. It is good also as.

  That is, if one of the first and second pulleys is a drive pulley and the other is an idler pulley, the belt transmission device is a device having a clutch mechanism. Further, if one of the first and second pulleys is a high speed ratio pulley and the other is a low speed ratio pulley, the belt transmission device is a device having a speed change mechanism.

  Thus, the belt transmission device discontinues power transmission by shifting the transmission belt between the first and second pulleys, so that an electromagnetic clutch is not required and power transmission is interrupted. This is advantageous in smoothly changing the speed and reducing the load fluctuation of the transmission belt.

  The transmission belt may be of any kind, such as a flat belt or a toothed belt (timing belt). In the case of a flat belt, either the inner surface (transmission surface) or the outer surface (back surface) may be brought into contact with the pulley body, but in the case of a toothed belt, the outer surface (back surface) is preferably brought into contact with the pulley body.

  When the transmission belt is a flat belt, it is preferable that the flat belt is wound around the driving pulley at a contact angle larger than 180 degrees. By doing so, the contact angle between the transmission belt (flat belt) and the driving pulley decreases, so that the initial tension (necessary loosening tension) decreases, and among the distributed loads from the flat belt to the driving pulley, each other The components facing each other in the diameter direction are canceled. As a result, the axial load on the driving pulley can be reduced.

  The engine accessory drive system according to the present invention includes a crank pulley that is integrally fixed to the engine crankshaft, and a first pulley and a second pulley that are attached to a rotating shaft of the accessory and arranged in parallel in the direction of the rotating shaft. An auxiliary drive pulley including a pulley, a transmission belt wound between the crank pulley and the auxiliary drive pulley, a pulley body around which the transmission belt is wound, and the pulley body rotatable around a pulley shaft And a pulley for a transmission belt having support means for swingably supporting around a predetermined pivot axis. The pivot shaft of the transmission belt pulley is tilted at a predetermined tilt angle to the front side in the rotational direction of the pulley body with respect to the axial load direction when viewed along the pulley shaft direction, and the support means includes the pulley The main body is configured to reciprocate in the pulley shaft direction together with the pivot shaft.

  The auxiliary machine drive system is interposed between a vacuum cylinder that moves the pulley body in the pulley axial direction together with the pivot by the suction negative pressure of the engine, and the engine and the vacuum cylinder. And a tank for storing a negative suction pressure.

  As described above, the transmission belt pulley includes the pivot shaft tilted at a predetermined tilt angle on the front side in the rotational direction of the pulley body with respect to the axial load direction when viewed along the pulley axial direction. Since the pulley body to be wound is supported so as to be able to reciprocate in the pulley axis direction together with the pivot shaft, the traveling position of the transmission belt can be changed by moving the pulley body while preventing the transmission belt from moving in the stationary state. Is possible. That is, in the engine accessory drive system, the belt can be moved between the first and second pulleys of the accessory drive pulley.

  In the engine accessory drive system, the suction negative pressure of the engine can be effectively used by providing a vacuum cylinder as a power source for moving the pulley body, while the vacuum cylinder and the engine are in between. By providing a tank for storing the suction negative pressure of the engine, a negative pressure necessary for the movement of the pulley body can be obtained regardless of the operating state of the engine (the magnitude of the suction negative pressure with respect to the throttle opening).

  As described above, according to the present invention, the pulley body is supported by the support means so as to be rotatable about the pulley shaft and swingable about the pivot shaft, and the pivot load is observed along the pulley shaft direction. Since the pulley body is inclined at a predetermined inclination angle to the front side in the rotation direction of the pulley body, the pulley body can be at least inclined when the transmission belt is offset on the pulley body, and the pulley body is In the state of being stationary with respect to the pulley axial direction, the lateral movement and meandering of the transmission belt can be quickly and reliably eliminated.

  Since the pulley body can be reciprocated in the pulley axis direction together with the pivot shaft, the transmission belt can be moved following the movement of the pulley body by a return force acting on the transmission belt, and the structure is simple. You can change the travel position of the transmission belt.

  Further, according to the belt transmission device in which the pulley for the transmission belt is pressed so as to apply tension to the transmission belt, the transmission belt can meander and shift while being given a stable tension. Since it is possible to prevent the transmission belt from being fully utilized and the transmission position of the transmission belt can be changed, various belt transmissions including, for example, a clutch mechanism and a transmission mechanism can be achieved. Can be used in the device.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  In the belt transmission device shown in FIG. 1, 1 is a driving pulley (flat pulley), 2 is a driven pulley (flat pulley), and a transmission belt (flat belt) 3 is wound around both pulleys 1 and 2, A transmission belt pulley (tension pulley) 4 is pressed against the back surface of the transmission belt 3 to apply tension to the transmission belt 3. As will be described later, this belt transmission device is a transmission device including a clutch mechanism.

  As shown in FIGS. 2 and 3, the driving pulley 1 is a pulley having a width approximately twice the width of the transmission belt 3, and is fitted into a driving shaft 1a that is an output shaft of a driving motor (not shown). Thus, it is integrally rotated with the driving shaft 1a.

  A pivot end of a urging arm 16 that urges the transmission belt pulley 4 to a side pressing the transmission belt 3 is attached to the front end side of the driving shaft 1a with respect to the driving pulley 1 via a bearing. Thus, the urging arm 16 is provided on the driving shaft 1a so as to be relatively rotatable.

  The driven pulley 2 is attached to a driven shaft 2a arranged in parallel to the driving shaft 1a. The driven pulley 2 includes two pulleys, a driving pulley 22 and an idler pulley 23 arranged in the axial direction of the driven shaft 2a.

  The drive pulley 22 is fitted to the distal end of the driven shaft 2a and is integrally rotated with the driven shaft 2a, whereas the idler pulley 23 is closer to the proximal end than the drive pulley 22 on the driven shaft 2a. The driven shaft 2a is extrapolated through a bearing, and the idler pulley 23 is rotatable relative to the driven shaft 2a. The drive pulley 22 and the idler pulley 23 are disposed so that a slight gap is formed between the two pulley surfaces, and the two pulley surfaces are substantially flush with each other. As shown in FIG. 2, when the transmission belt 3 is wound around the drive pulley 22, the transmission belt 3 is in a power transmission state in which the power of the driving shaft 1a is transmitted to the driven shaft 2a. As shown in FIG. 3, when the transmission belt 3 is wound around the idler pulley 23, the power of the driving shaft 1a is not transmitted to the driven shaft 2a.

  As shown in FIGS. 4 and 5, the transmission belt pulley 4 includes a pulley body 5 around which the transmission belt 3 is wound, and the pulley body 5 is rotatable about the pulley axis C1 and swingable about the pivot axis C2. And supporting means 10 for supporting.

  The support means 10 includes a cylindrical shaft member 11 that supports the pulley body 5 by a bearing 12, a support rod 13, a pin 17 that forms a pivot C2, and the pulley body together with the pin 17 in the pulley axis C1 direction. And a moving mechanism 6 that reciprocates. The moving mechanism 6 includes an intermediate member 14 and a vacuum cylinder 7.

  The support rod 13 includes an attachment part 13a attached to the urging arm 16 and a support part 13b provided following one end of the attachment part 13a. The mounting portion 13a is fixed to the tip of the urging arm 16 with a nut. The support portion 13b is inserted into the intermediate member 14.

  The support portion 13b has an end opposite to the attachment portion 13a (hereinafter, an end opposite to the attachment portion 13a is referred to as a distal end of the support portion 13b, and an end on the attachment portion 13a side is a base end of the support portion 13b. An insertion hole 91 that is open on the surface of each other and two elongated holes 92 that are opposed to each other in the radial direction and extend in the axial direction. A thread groove is formed in the vicinity of the opening of the insertion hole 91, and the opening is closed by screwing a stud bolt 93 described later.

  The intermediate member 14 is a tubular member having a circular cross section as a whole, which includes two halved members and has a center hole at the center of the cross section. The intermediate member 14 is inserted into the cylindrical shaft member 11 and is supported by the support rod 13 via sliding rings 21 and 21 fitted on the proximal end side and the distal end side, respectively. 13b is extrapolated. And this intermediate member 14 is supported by the said support part 13b so that a reciprocation is possible in the axial direction.

  The intermediate member 14 has an enlarged diameter portion at the tip thereof, and the enlarged diameter portion is fixed to the movable plate 72 of the vacuum cylinder 7. Thus, as will be described in detail later, the intermediate member 14 reciprocates in the axial direction of the support portion 13b using the vacuum cylinder 7 as a power source.

  Further, the portion corresponding to the diameter direction in the intermediate member 14 is cut into a D-shape, and flat sliding surfaces 14c and 14c which are parallel to each other as shown in FIGS. Is formed. Thus, through holes extending in the radial direction from the sliding surfaces 14c toward the center hole of the intermediate member 14 are formed, and the sliding cylinder 18 is fitted in the through holes.

  Two sliding members 19 each having a D-shaped cross section are attached to the inner peripheral surface of the shaft member 11 so as to face each other in the diametrical direction. The sliding member 19 is formed on the inner surface of the shaft member 11 such that flat sliding surfaces 11a and 11a that are slidably in contact with the sliding surfaces 14c and 14c of the intermediate member 14 face each other. ing. Further, arcuate surfaces on both sides connecting both side edges of the sliding surfaces 11 a and 11 a are formed by the inner peripheral surface of the shaft member 11. Further, the shaft member 11 and the sliding member 19 are formed with support holes into which the pins 17 are fitted near the center of the width of the pulley body 5.

  The sliding member 19, the sliding cylinder 18 and the sliding ring 21 may be made of resin.

  The pins 17 of the support means 10 are disposed through the long holes 92 of the support rod 13 so as to penetrate the support portion 13b in the radial direction, and both ends thereof are through holes of the intermediate member 14, respectively. Is inserted into the support holes provided in the shaft member 11 and the sliding member 19 through the sliding cylinder 18 fitted in the shaft. The pin 17 is disposed at a predetermined tilt angle α on the front side in the rotation direction of the pulley body 5 with respect to the axial load direction L with respect to the rotation direction of the pulley body 5 (see FIG. 4). With respect to the width direction of the pulley body 5, it is arranged near the center (see FIG. 5).

  Thus, the shaft member 11 and the pulley body 5 swing around the pivot C2 formed by the pin 17 between the arc surfaces on both sides of the intermediate member 14 and the arc surfaces on both sides of the cylindrical hole of the shaft member 11. Clearances 15, 15 that allow movement are formed.

  As the intermediate member 14 reciprocates along the support portion 13b, the pin 17 moves in the long hole 92 in the axial direction, whereby the shaft member 11 and the pulley engaged with the pin 17 are moved. The main body 5 reciprocates along the support portion 13b.

  A compression spring 94 is disposed in the insertion hole 91 of the support portion 13b, and a stud bolt 93 is screwed into the insertion hole 91 in this state. The compression spring 94 disposed between the implantation bolt 93 and the pin 17 biases the pin 17 toward the proximal end side of the support portion 13b.

  The vacuum cylinder 7 is extrapolated to the support rod 13 and has two side plates 71 and 72 opposed to each other in the axial direction thereof, and an expansion / contraction part 73 that connects the peripheral surfaces of the side plates 71 and 72 to each other, It is configured with.

  One of the two side plates 71, 72 is a fixed plate 71 fixed to the distal end portion of the support portion 13b, and the other is movable to the support portion 13b on the base end side of the fixed plate 71. It is the movable plate 72 supported by. An O-ring is interposed between the inner peripheral surfaces of the two side plates 71 and 72 and the outer peripheral surface of the support rod 13, thereby ensuring airtightness in the vacuum cylinder 7. .

  The fixed plate 71 is provided with a connection port 75 connected to a vacuum pump (not shown) via a tube 74, whereas the movable plate 72 is fixed with a diameter-expanded portion of the intermediate member 14. Has been. Then, as shown in FIG. 2, when the vacuum pump 7 is driven to a negative pressure by driving the vacuum pump from the normal pressure inside the vacuum cylinder 7, the movable plate 72 is compressed. When the spring 94 moves against the urging force of the spring 94 toward the fixed plate 71, the intermediate member 14 moves along with the tip of the support rod 13, and the pin 17, the shaft member 11, and the pulley body 5 are integrated. Then, it moves to the front end side of the support rod 13 (see FIG. 3). As shown in FIG. 3, the pin 17, the shaft member 11, the biasing force of the compression spring 94 is applied to the normal pressure inside the vacuum cylinder 7 from the negative pressure inside the vacuum cylinder 7. And the pulley main body 5 is united and moves to the base end side of the support rod 13, and accordingly, the intermediate member 14 and the movable plate 72 move to the base end side of the support rod 13 (see FIG. 2). Thus, the pulley body 5 and the pin 17 have a power transmission position (FIG. 2) corresponding to the position of the drive pulley 22 of the driven pulley 2 and a power cutoff position (FIG. 3) corresponding to the idler pulley 23. The position is changed to two positions.

  FIG. 7 shows a state of use shown in FIG. 1, 2 or 3, that is, in a state where the pulley main body 5 is positioned and stationary at the power transmission position, or in a state where the pulley main body 5 is positioned and stationary at the power cutoff position. Thus, when the transmission belt 3 hung near the center of the width of the pulley body 5 approaches the one side of the pulley body 5 from the center of the pulley body 5 as shown by the chain line, the shaft load is shifted from the position of the pin 17 to one side of the pulley body 5. Thus, it acts on the shaft member 11. As a result, a rotational moment about the pin 17 acts on the shaft member 11, and the shaft member 11 rotates and displaces around the pin 17 together with the pulley body 5.

  That is, as shown in FIG. 6, the intermediate member 14, the pin 17, and the shaft member 11, when the axial load direction is parallel to the pin 17 (when L0), the transmission belt 3 moves from the center of the pulley body 5 Even if it moves to one side, the rotational moment around the pin 17 does not occur. On the other hand, when the direction of the axial load becomes L inclined by an angle α with respect to the direction of the pin 17, when the transmission belt 3 approaches the one side from the center of the pulley body 5, A rotational moment around 17 is generated, and the shaft member 11 is rotationally displaced. The angle α corresponds to the tilt angle α of the pin 17 with respect to the direction of the axial load L.

  Then, in the case of FIG. 4, the pulley body 5 is rotated around the pin 17 on which the pulley body 5 is tilted by the axial load L, so that the pulley body 5 is connected to the transmission belt 3 as shown in FIG. 7 (plan view). As shown in FIG. 8 (indicated by arrow VIII in FIG. 4), the transmission belt 3 is in an oblique state with respect to the transmission belt 3 so that the side from which the side is offset becomes the front side in the belt traveling direction. Is inclined in the direction of the axial load L so that the side from which the deflection is offset is low and the opposite side is high. 4, 7 and 8, the state in which the pulley body 5 is rotationally displaced is indicated by a chain line.

  Accordingly, the transmission belt 3 is subjected to a return force (a force for returning the offset) due to the pulley body 5 being in an oblique state and a return force due to the inclination of the pulley body 5. This offset of 3 is prevented. That is, in a state where the pulley body 5 is stationary with respect to the pulley axis C1 direction, the transmission belt 3 is transmitted by the return force caused by the pulley body 5 being obliquely inclined and the characteristics of the belt transmission device. The vehicle travels at a position where the offset force acting on the belt 3 is balanced. Even if the transmission belt 3 is largely displaced, the transmission belt 3 is returned to a position where the return force and the offset force are balanced.

  Further, the sliding surfaces 14c and 11a of the intermediate member 14 and the shaft member 11 are brought into contact with each other by the axial load, and an appropriate sliding resistance acts between the both sliding surfaces 14c and 11a. Therefore, when the transmission belt 3 is traveling near the center of the pulley body 5, the pulley body 5 can be prevented from slightly swinging due to traveling vibration of the transmission belt 3, and the transmission belt 3 is offset. When this occurs, the pulley main body 5 reacts with extreme sensitivity and is rotationally displaced, thereby preventing the pulley main body 5 from causing hunting that swings left and right in small increments.

  If the transmission belt pulley 4 is used as a tension pulley as in the above embodiment, a stable tension can be applied to the transmission belt 3, which is advantageous in fully exhibiting the transmission capability of the transmission belt 3. .

  Then, as shown in FIG. 2, the pulley body 5 is positioned at the power transmission position and the transmission belt 3 is wound around the drive pulley 22, so that the inside of the vacuum cylinder 7 is set to a negative pressure and the pulley body 5 Is moved toward the distal end side of the support rod 13 (left side in FIG. 2), the transmission belt 3 is relatively displaced toward the proximal end side of the support rod 13 on the pulley body 5, and the axial load L of the pivot C2 is increased. The shaft body 11 is shifted from the position to one side in the width direction of the pulley body 5. Due to the axial load L, as described above, the pulley body 5 is rotationally displaced about the pivot C2 to return the offset from the pulley body 5 to the transmission belt 3, that is, the distal end side of the support rod 13 (left side in FIG. 2). ) The power to go to work. Therefore, if the pulley body 5 is continuously moved toward the distal end side of the support rod 13, a force toward the distal end side of the support rod 13 continues to act on the transmission belt 3, and the transmission belt 3 is connected to the pulley body. 5 is moved to the front end side of the support rod 13. Then, as shown in FIG. 3, when the pulley main body 5 is located at the power cutoff position, the transmission belt 3 is wound around the idler pulley 23, and the power transmission to the driven shaft 2a is performed. Will be blocked.

  On the contrary, as shown in FIG. 3, when the pulley main body 5 is positioned at the power cut-off position and the transmission belt 3 is wound around the idler pulley 23, the inside of the vacuum cylinder 7 is brought to normal pressure and the compression spring 94 When the pulley body 5 is moved to the base end side (right side in FIG. 3) of the support rod 13 by the urging force, the transmission belt 3 is relatively displaced toward the tip end side of the support rod 13 on the pulley body 5. The axial load L is shifted from the position of the pivot C2 to one side in the pulley body 5 width direction and acts on the shaft member 11. As described above, the pulley body 5 is rotationally displaced around the pivot C2 by the axial load L, and the force that returns the offset from the pulley body 5 to the transmission belt 3, that is, the base end side of the support rod 13 (FIG. 3). The force toward (right side) works. Therefore, if the pulley body 5 is continuously moved toward the base end side of the support rod 13, a force toward the base end side of the support rod 13 continues to act on the transmission belt 3, and the transmission belt 3 Following the movement of the pulley body 5, it moves to the proximal end side of the support rod 13. Then, as shown in FIG. 2, when the pulley body 5 is positioned at the power transmission position, the transmission belt 3 is wound around the drive pulley 22, and the power is transmitted to the driven shaft 2a. Will be.

  As described above, the belt transmission device does not forcibly change the traveling position of the transmission belt 3 by, for example, applying the transmission belt 3 to a flange provided on the pulley body 5, but the return force acting on the transmission belt 3 from the pulley body 5. Therefore, the pulley main body 5 does not need a flange because the traveling position of the transmission belt 3 is changed. In other words, there is no decrease in belt life due to flange contact. The pulley body 5 may be provided with a flange. This is effective for preventing the transmission belt 3 from falling off when the pulley body 5 is moved in the pulley axial direction with the rotation of the pulley body 5 stopped.

  Here, when the traveling speed of the pulley body 5 in the pulley axis direction is faster than the speed at which the transmission belt 3 moves in the pulley axis direction, especially when the traveling speed of the transmission belt 3 is low, the transmission belt 3 Since it falls off, it is assumed that the moving speed of the pulley body 5 is slower than the moving speed of the transmission belt 3. The moving speed of the transmission belt 3 is the belt traveling speed, belt length, span length, load, belt characteristics (癖), transmission layout, tilt angle α, rotational displacement of the pulley body 5, Since it depends on other factors, the moving speed of the pulley body 5 may be set as appropriate based on these factors.

  Further, the belt transmission device realizes intermittent transmission of power even without an electromagnetic clutch, and is advantageous in reducing the load fluctuation of the transmission belt by smoothly performing intermittent transmission or shifting of power transmission.

  A loose crown may be attached to the outer peripheral surface of the pulley body 5. If the crown is gentle, it is possible to avoid applying a large load to the transmission belt 3.

  In the belt transmission device, the driven pulley 2 is composed of a drive pulley 22 and an idler pulley 23 and has a clutch mechanism. However, the invention is not limited to this, and the driven pulley 2 is replaced with a high speed ratio pulley. And a low-speed ratio pulley can be configured as a device having a speed change mechanism.

  Further, in the belt transmission device, the power source for reciprocating the intermediate member 14 is constituted by the vacuum cylinder 7. However, the power source is not limited to this, and various devices such as a motor, a linear motor, a solenoid, and a hydraulic cylinder are used. Is available. In addition, the belt transmission device is configured such that the transmission belt 3 travels at two different travel positions, but the power source of the intermediate member 14 is configured by a stepping motor or the like, so that It is also possible to travel at the above travel position.

(Embodiment 2)
9 and 10 show the layout of the belt and pulley when the belt transmission device according to the present invention is applied to the gas heat pump system A, and FIG. 11 is a refrigerant system diagram of the gas heat pump system A. This gas heat pump system A intermittently transmits driving force between a gas engine GE as a prime mover and a compression mechanism as a driving device connected to the refrigerant circuit 43. The refrigerant circuit 43 includes the compression mechanism that compresses the refrigerant, the condenser 44 that condenses the compressed refrigerant, the expansion mechanism 45 that decompresses the condensed refrigerant, and the evaporator 46 that evaporates the decompressed refrigerant. Are connected in order, and the refrigerant is enclosed, and the refrigeration cycle operation and the heat pump cycle operation are performed. The compression mechanism includes a first compressor 41 and a second compressor 42, and both the compressors 41 and 42 are connected to the refrigerant circuit 43 in parallel with each other. The refrigerant circuit 43 is provided, for example, in an air conditioner for building air conditioning.

  9 and 10, reference numeral 30 denotes a driving pulley that is fixedly attached to a crankshaft 30 a of a gas engine GE that is a driving shaft. Reference numerals 31 and 32 denote first and second driven pulleys provided on the rotation shafts 31a and 32a of the first compressor 41 and the second compressor 42, respectively. Further, reference numeral 33 denotes a tension pulley of the auto tensioner 34 for adjusting the tension of the transmission belt 3, and 4 denotes a transmission belt pulley (idler pulley).

  The driving pulley 30, the first and second driven pulleys 31, 32, the tension pulley 33, and the transmission belt pulley 4 are all flat pulleys, and the transmission is a flat belt between the pulleys 30 to 33, 4. A belt 3 is wound around.

  The transmission belt 3 is in a forward-bending state in which the inner peripheral surface as the transmission surface is in contact with the pulleys 30 to 32 in the driving pulley 30 and the first and second driven pulleys 31 and 32, respectively. The tension pulley 33 and the transmission belt pulley 4 are wound in a reverse bending state in which the outer peripheral surface (rear surface) is in contact with the pulleys 33 and 4, respectively.

  Then, due to the rotation of the crankshaft 30a (driving side pulley 30) accompanying the operation of the gas engine GE, the belt 3 becomes the driving side pulley 30 → the tension pulley 33 → the second driven side pulley 32 → the first driven side pulley 31 → the transmission belt. The first and second compressors 41 and 42 are driven by traveling in the clockwise direction in the figure in the order of the pulley 4 for driving → the pulley 30 on the driving side.

  Here, as in the belt layout shown in FIG. 9, the belt 3 is reversely bent by the tension pulley 33 and the transmission belt pulley 4 to increase the contact angle between the pulleys 30 to 33 and 4 and the belt 3. Thus, the initial tension (required tension on the loose side) can be reduced. Further, by making the belt contact angle of the driving pulley 30 larger than 180 °, components that are opposed to each other in the diametrical direction among the distributed loads from the belt 3 to the pulley 30 are canceled (shaded lines in FIG. 9). Part reference). As a result, the axial load acting on the crankshaft 30a can be reduced, and the durability of the engine GE can be improved.

  As shown in FIG. 10, the driving-side pulley 30 is a pulley having a width approximately three times the width of the transmission belt 3, and is fitted into the crankshaft 30a and is integrally rotated with the crankshaft 30a. ing.

  The first driven pulley 31 is attached to the rotating shaft 31a of the first compressor 41 as described above, and the first driven pulley 31 includes a driving pulley 31b aligned in the axial direction of the rotating shaft 31a. , Consisting of two pulleys, an idler pulley 31c. The drive pulley 31 b is a pulley having a width approximately twice the width of the transmission belt 3, and the idler pulley 31 c is a pulley having substantially the same width as the transmission belt 3. The drive pulley 22 is fitted to the tip of the rotating shaft 31a (the right end in FIG. 10) and is integrally rotated with the rotating shaft 31a, whereas the idler pulley 31c is connected to the rotating shaft 31a. A base end side (left side in FIG. 10) of the driving pulley 31b is extrapolated to the rotating shaft 31a via a bearing, and the idler pulley 31c is rotatable relative to the rotating shaft 31a. .

  The second driven pulley 32 is attached to the rotating shaft 32a of the second compressor 42 as described above, and the second driven pulley 32 is arranged in the axial direction of the rotating shaft 32a. 3 comprises two pulleys: a drive pulley 32b having a width approximately twice the width of 3 and an idler pulley 32c having a width substantially the same as the width of the transmission belt 3. The drive pulley 32b is fitted into the base end of the rotating shaft 32a, whereas the idler pulley 32c is located on the distal end side of the rotating shaft 32a with respect to the rotating shaft 32a via a bearing. Is extrapolated.

  In the first and second driven pulleys 31 and 32, the drive pulleys 31b and 32b and the idler pulleys 31c and 32c are arranged so that a slight gap is formed between the two pulley surfaces. In addition, the two pulley surfaces are substantially flush with each other.

  In the first embodiment, the transmission belt 3 travels at two different travel positions. In the second embodiment, the transmission belt 3 travels at three different travel positions. . That is, in the state in which the transmission belt 3 is positioned on the most proximal side of each of the shafts 30a, 31a, and 32a, the first driven pulley 31 has the belt 3 wound around the idler pulley 31c, while the second driven side In the pulley 32, the belt 3 is wound around the drive pulley 32 b, whereby the power of the crankshaft 30 a is not transmitted to the first compressor 41 but transmitted to the second compressor 42 (first state). ) In the state where the transmission belt 3 is positioned at the most distal end side of each of the shafts 30a, 31a, 32a, the first driven pulley 31 has the belt 3 wound around the drive pulley 31b, while the second driven pulley In 32, the belt 3 is wound around the idler pulley 32c, whereby the power of the crankshaft 30a is transmitted to the first compressor 41 and not transmitted to the second compressor 42 (second state). .

  When the transmission belt 3 is located at the center of the driving pulley 30, the belt 3 is wound around the driving pulleys 31b and 32b of the first and second driven pulleys 31 and 32, respectively. The power of the shaft 30a is transmitted to the first and second compressors 41 and 42 (third state).

  Since the transmission belt pulley 4 has substantially the same configuration as the transmission belt pulley 4 of the first embodiment, detailed illustration thereof is omitted here, but the transmission belt pulley 4 of the second embodiment is A pulley body 5 around which the transmission belt 3 is wound, and support means for supporting the pulley body so as to be rotatable about the pulley axis C1 and swingable about the pivot axis C2.

  And the support means of the pulley 4 for transmission belts in Embodiment 2 comprises the cylindrical shaft member 11 which supports the pulley main body 5 with the bearing 12, the support rod 13, and the pivot C2, similarly to Embodiment 1. FIG. One of the pins 17 and the moving mechanism 6 that reciprocates the pulley main body in the direction of the pulley axis C1 together with the pin 17 (see FIGS. 4 and 5) are configured (see FIGS. 4 and 5). The intermediate member 14 is supported by the rod 13 so as to be capable of reciprocating in the axial direction thereof, and a stepping motor 7a serving as a power source that replaces the vacuum cylinder.

  That is, although not shown in detail, the stepping motor 7a is connected to the intermediate member 14 so as to reciprocate the intermediate member 14 in the axial direction of the support rod 13. Accordingly, in the second embodiment, the stepping motor 7 a is controlled by a controller (not shown) to move the pulley body 5 via the intermediate member 14, whereby the pulley body 5 is moved to the pulley surface of the driving pulley 30. Are positioned at three positions corresponding to the base end side, the center, and the tip end side (see the solid line and the two-dot chain line in FIG. 10), and thereby the transmission belt 3 is moved in the pulley axial direction. ~ The third state is switched.

  Therefore, according to the present embodiment, the power interruption between the gas engine GE and the compressors 41 and 42 can be performed without providing an electromagnetic clutch, and the transmission belt 3 includes the drive pulleys 31b and 32b and the idler pulley 31c, Since power is interrupted by moving between 32c, power transmission can be smoothly interrupted and the compressors 41 and 42 can be started and stopped smoothly. As a result, torque fluctuations of the compressors 41 and 42 can be reduced, the life of the compressors 41 and 42 can be extended, load fluctuations of the transmission belt 3 can be reduced, and durability of the transmission belt 3 can be reduced. Can be improved. Further, since the electromagnetic clutch can be omitted, the number of parts can be reduced and the power consumption can be reduced, thereby reducing the cost.

  In addition, since a flat belt is used as the transmission belt 3, the bending loss of the belt 3 can be reduced and power transmission efficiency can be improved as compared with the configuration using the V belt. Durability can be improved. In addition, since the durability of the belt 3 is improved, the maintainability as a belt transmission device can also be improved.

  In the present embodiment, since the transmission belt 3 can travel at three travel positions and the first to third states are realized, the driving and stopping of the compressors 41 and 42 of the refrigerant circuit 43 are respectively performed according to the heat load. Can be combined and can be easily adjusted to the desired compressor capacity.

  In addition, about the said embodiment, the transmission belt 3 can be drive | worked by two driving | running | working positions, and, thereby, for example, the power to the 1st compressor 41 is intermittently transmitted, while the power transmission to the 2nd compressor 42 is always performed. It may be configured.

(Embodiment 3)
12 and 13 show the layout of belts and pulleys when the belt transmission according to the present invention is an auxiliary machine drive system B for an automobile engine. In the figure, reference numeral 51 denotes a crank pulley that is rotatably fixed integrally to a crankshaft 51a of the engine E that is a driving shaft. Reference numerals 52 to 56 and 4 are driven pulleys, respectively. For example, 52 is a PS pump pulley that is fixedly attached to a rotating shaft of a power steering pump (not shown) that is an engine accessory, and 53 is Similarly, an alternator pulley fixed to a rotating shaft of an alternator (not shown), and 54 is a compressor pulley fixed to the rotating shaft of an air conditioner compressor (not shown). Further, 55 is a tension pulley of the auto tensioner 57 for adjusting the tension of the (first) transmission belt 3a, 56 is an idler pulley, and 4 is a tension of the (second) transmission belt 3b. This is a transmission belt pulley (tension pulley).

  The crank pulley 51, PS pump pulley 52, an alternator pulley 53, a compressor pulley 54, tension pulley 55, will both idler pulleys 56 and drive belt pulley 4 from the flat pulley, the flat belt between the pulleys 51～56,4 First and second transmission belts 3a and 3b are wound around. These flat belts 3a and 3b may be cord flat belts having a cord as an example.

  Although not shown in detail, the auto tensioner 57 includes a fixing portion 70 fixed to the engine E side and a rotating arm 71 rotatably supported by the fixing portion 70. A tension pulley 55 is rotatably supported on the distal end side. A spring member such as a torsion coil spring is accommodated in the fixed portion, and the rotating arm 71 is urged to rotate in the direction in which the tension pulley 55 presses the first flat belt 3a by the torsional torque. The tension of the first flat belt 3a is maintained substantially constant.

  As shown in FIG. 13, the crank pulley 51 includes a first crank pulley 51b around which the first flat belt 3a is wound and a second crank pulley 51c around which the second flat belt 3b is wound. Unlike the first crank pulley 51b, the pulley 51c is a pulley having a width approximately twice the width of the second flat belt 3b.

  In addition, the compressor pulley 54 is fitted to the distal end of the rotary shaft 54a of the compressor and is rotated to the base end side of the drive pulley 54b in the rotary shaft 54a. It comprises an idler pulley 54c which is extrapolated via a bearing to the shaft 54a and is rotatable relative to the rotating shaft 54a.

  In the first flat belt 3a, the crank pulley 51 (first crank pulley 51b) and the driving pulleys 52 and 53 of each auxiliary machine have their inner peripheral surfaces which are transmission surfaces in contact with the pulleys 52 and 53, respectively. The tension pulley 55 and the idler pulley 56 are wound in a reverse bending state in which the outer peripheral surface (back surface) is in contact with the pulleys 55 and 56, respectively, and are wound in a so-called serpentine layout. Then, the rotation of the crankshaft 51 a (crank pulley 51) accompanying the operation of the engine E causes the first flat belt 3 a to move from the crank pulley 51 → the tension pulley 55 → the PS pump pulley 52 → the alternator pulley 53 → the idler pulley 56 → the crank pulley 51. Sequentially run in the clockwise direction in the figure.

  Further, the second flat belt 3b is wound in a positive bending state in which the inner peripheral surface of the crank pulley 51 (second crank pulley 51c) and the compressor pulley 54 is in contact with the pulleys 51 and 54, respectively. The transmission belt pulley 4 is pressed against the back surface so as to apply tension to the second flat belt 3b. Then, the rotation of the crankshaft 51a (crank pulley 51) accompanying the operation of the engine E causes the second flat belt 3b to rotate clockwise in the figure in the order of the crank pulley 51 → the compressor pulley 54 → the transmission belt pulley 4 → the crank pulley 51. It runs and drives the compressor.

  In this embodiment, the idler pulley 56 swings so as to return the first flat belt 3a as it is offset, and automatically adjusts the traveling position of the first flat belt 3a. It is said.

  This self-aligning pulley is configured equivalently to the transmission belt pulley shown in FIGS. 4 and 5 except that the pulley body is reciprocated in the pulley axial direction together with the pivot shaft. For example, as shown in FIGS. 14 and 15, a cylindrical pulley body 60 around which the first flat belt 3 a is wound, and a cylindrical shape in which the pulley body 60 is rotatably supported around a pulley shaft C <b> 1 by a bearing 61. A shaft member 62 and a support rod 63 that supports the shaft member 62 via a pin 64 constituting the pivot C2 so as to be swingable around a pivot C2 orthogonal to the pulley shaft C1. Become.

  The support rod 63 is formed with a flange 63a on the base end side in the longitudinal direction, and the flange 63a is fastened to a bracket 69 or the like and fixed to the side wall of the cylinder block of the engine E, while the shaft member 62 is fixed. As shown in FIG. 15 (b), the tip side portion to be inserted into the cylindrical hole is formed in a D-shaped cross section obtained by cutting a circular rod in a cross section vertically in half, and a flat surface on the outer periphery thereof. 63b (hereinafter referred to as a D-cut surface) is disposed so as to be substantially orthogonal to the pivot C2.

  Further, a through hole having a circular cross section extending in the radial direction of the support rod 63 along the pivot axis C2 is formed in the vicinity of the center of the portion formed in a D-shaped cross section on the distal end side of the support rod 63. One end of the hole (the lower end in the figure) opens to the D-cut surface 63b, while the other end of the through hole opens to the outer peripheral arc surface on the distal end side of the support rod 63.

  On the other hand, the cylindrical hole of the shaft member 62 is formed in a D-shaped cross section corresponding to the cross-sectional shape on the front end side of the support rod 63. That is, a flat facing surface 62a that faces the D-cut surface 63b of the support rod 63 in the direction of the pivot C2 is formed on the cylindrical inner surface of the shaft member 62 so as to be orthogonal to the pivot C2. A circular arc surface is formed so as to surround the outer peripheral circular arc surface, and each of the opposed surface 62a and the circular arc surface has a circular cross section so as to open at a portion corresponding to the through hole of the support rod 63 and to extend along the pivot C2. Support holes are formed.

  And the said pin 64 is penetrated by the through-hole of the said support rod 63, and the both ends of this pin 64 are each inserted in the support hole of the said shaft member 62 (namely, the pin 64 is the width | variety of the pulley main body 60). It is arrange | positioned at the approximate center part, and orthogonally crosses D cut surface 63b of the support rod 63, and the opposing surface 62a of the shaft member 62). A cylindrical resin sliding material 65 is disposed between the outer peripheral surface of the pin 64 and the inner surface of the through hole of the support rod 63, while the D-cut surface 63 b of the support rod 63 and the shaft member 62 are in contact with each other. A needle bearing 66 (may be a ball bearing or the like) having a substantially disk shape is interposed between the facing surface 62a.

  With this configuration, the shaft member 62 and the pulley main body 60 are supported so as to be swingable around the pin 64 (the pivot C2) with respect to the support rod 63, and approximately at the center position of the width of the first flat belt 3a. Is shifted from a substantially central position of the width of the pulley body 60, that is, a position in the width direction corresponding to the pivot C2 on the outer peripheral surface of the pulley body 60 (hereinafter, also simply referred to as the position of the pivot C2). The shaft load acting on the shaft member 62 due to the tension of 3a receives a turning moment generated around the pivot C2 and swings around the pin 64.

  The shaft member 62 is connected to the pulley body 60 with the pin 64 as an axis between the arc surface on the outer periphery of the rod continuous with the D-cut surface 63b of the support rod 63 and the arc-shaped cylindrical inner surface of the shaft member 62 surrounding the rod. At the same time, a gap is formed to allow swinging.

  Thus, the idler pulley 56 is generated by the tension of the first flat belt 3a in the accessory drive system B as shown in FIG. 12, as described in the first embodiment, when viewed along the pulley axis C1. With respect to the direction of the axial load L to be applied, the pivot C2 is disposed in a state tilted by a predetermined angle α on the front side in the rotational direction of the pulley body 60 (on the front side in the belt traveling direction). Thus, when the first flat belt 3a running around the pulley body 60 is shifted in the width direction, the pulley body 60 is inclined in the axial load direction due to the shift of the axial load position, and the first flat belt 3a is inclined. Inclined with respect to the traveling direction of the belt 3a, the first flat belt 3a is shifted back.

  On the other hand, the second crank pulley 51c, the compressor pulley 54, and the transmission belt pulley 4 constitute a belt transmission device having a clutch mechanism, similar to the belt transmission device in the first embodiment.

  That is, as shown in FIG. 13, the transmission belt pulley 4 is urged toward the side pressed against the second flat belt 3b by the urging arm 16 attached to the crankshaft 51a. The configuration of the transmission belt pulley 4 is the same as that of the pulley 4 shown in FIGS. 4 and 5, and the pulley main body 5 around which the second flat belt 3b is wound and the pulley main body 5 are rotatable around the pulley axis C1. And a support means 10 that swingably supports around the pivot C2, and the support means 10 has a cylindrical shaft member 11 that supports the pulley body 5 by a bearing 12, a support rod 13, and a pivot. A pin 17 constituting C2, and a moving mechanism 6 for reciprocating the pulley main body in the direction of the pulley axis C1 together with the pin 17. The moving mechanism 6 includes an intermediate member 14, a vacuum cylinder 7, , And is configured.

  With this configuration, as described above, the pulley main body 5 is positioned at the power transmission position and the second flat belt 3b is wound around the drive pulley 54b (the state shown in FIG. 13). When the pulley body 5 is moved to the left side of FIG. 13 with negative pressure, the second flat belt 3b moves following the movement of the pulley body 5. Thus, the second flat belt 3b is wound around the idler pulley 54c, and the power transmission to the rotating shaft 54a of the compressor is interrupted (that is, the compressor is stopped).

  Conversely, from the state in which the pulley body 5 is positioned at the power cut-off position and the second flat belt 3b is wound around the idler pulley 54c, the inside of the vacuum cylinder 7 is brought to normal pressure and the pulley body 5 is moved to the right side of FIG. The second flat belt 3b moves following the movement of the pulley body 5 and is wound around the drive pulley 54b. As a result, power is transmitted to the rotating shaft 54a of the compressor (that is, the compressor is driven).

  Here, when the belt transmission device is applied to an engine accessory drive system as in the present embodiment, the negative suction pressure of the engine can be used as a power source for moving the pulley 4. That is, the vacuum cylinder 7 and an intake manifold (not shown) of the engine E are connected to each other by a tube having a control opening / closing valve, and the opening / closing of the control opening / closing valve is controlled so that the intake negative pressure of the engine It may be switched between setting the inside of the vacuum cylinder 7 to a negative pressure and setting the inside of the vacuum cylinder 7 to a normal pressure.

  In that case, the suction negative pressure of the engine E is related to the throttle opening, and the suction negative pressure decreases in proportion to the increase of the throttle opening. In contrast, the compressor driven by the engine E is subjected to acceleration cut control for stopping (OFF) when a large engine output is required, such as in the early stage of acceleration (when the accelerator opening is large at a low vehicle speed).

  Thus, when the pulley 4 is moved by setting the vacuum cylinder 7 to a negative pressure so as to perform acceleration cut control according to the operating state of the engine E, the pulley 4 can be moved in relation to the throttle opening. May not be able to obtain a negative suction pressure.

  Therefore, as shown in FIG. 13, it is preferable to provide a tank 81 and a control opening / closing valve 82, 83 that store negative pressure between the vacuum cylinder 7 and the engine E. Then, the control open / close valve 83 between the tank 81 and the engine E is controlled to open and close according to the operating state of the engine E, whereby the intake negative pressure of the engine E is stored in the tank 81, and the tank 81 and the vacuum It is only necessary to switch the driving / stopping of the compressor by moving the pulley 4 by controlling the opening / closing valve 82 between the cylinder 7 and the cylinder 7 according to the operating state of the engine E. Thus, regardless of the negative pressure state of the engine E, it is possible to perform clutch control of the compressor according to the operating state of the engine E using the negative pressure stored in the tank 81. Here, it is desirable for stable control that the capacity of the tank 81 is several times larger than the amount necessary for one clutch control.

It is a front view of a belt transmission device. It is a side view of the apparatus in the state which made the power transmission belt drive | work at a power transmission position. It is a side view of the apparatus in the state which made the power transmission belt drive | work at a power interruption position. It is a longitudinal cross-sectional view (IV-IV sectional view of FIG. 5) of a pulley. It is VV sectional drawing of FIG. It is a figure explaining that a rotational moment generate | occur | produces in a shaft member by the shaft load in the use condition of the pulley. It is a top view which shows the use condition of the pulley. FIG. 5 is a view taken along arrow VIII in FIG. 4. It is a figure which shows an example of the layout of a belt and a pulley at the time of applying a belt transmission apparatus to a gas heat pump system. It is a side view of the belt transmission device. It is a systematic diagram of a refrigerant circuit. It is a schematic block diagram at the time of applying a belt transmission apparatus to the auxiliary drive apparatus of an engine. It is a side view of the belt transmission device. It is the partial sectional view seen in the direction of the pivot which shows the example of composition of a self-aligning pulley. It is the partial sectional view which looked at the pulley in the direction orthogonal to a pivot.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drive pulley 2 Drive pulley 3 Drive belt 4 Drive belt pulley 5 Pulley body 6 Moving mechanism 7 Vacuum cylinder 10 Support means 11 Shaft member 13 Support rod 14 Intermediate member 17 Pin 22 Drive pulley 23 Idler pulley 51 Crank pulley 51a Crank Shaft 51b First crank pulley 51c Second crank pulley 54 Compressor pulley (auxiliary drive pulley)
54a Rotating shaft 54b Drive pulley (first pulley)
54c idler pulley (second pulley)
81 Tank C1 Pulley shaft C2 Axis E Engine α Tilt angle

Claims (6)

A pulley body around which a transmission belt is wound;
A support means for supporting the pulley body so as to be rotatable around a pulley axis and swingable around a predetermined pivot axis;
The pivot is tilted at a predetermined tilt angle on the front side in the rotational direction of the pulley body with respect to the direction of the axial load as viewed along the pulley axis direction,
The support means is
A cylindrical shaft member provided integrally with the pulley body and rotatably supporting the pulley body around the pulley shaft;
A support rod inserted into the cylindrical shaft member and extending coaxially with the pulley shaft;
A pin disposed near the center of the width of the pulley body to constitute the pivot,
An intermediate member interposed between the shaft member and the support rod, swingably supporting the shaft member around the pin, and reciprocating along the support rod together with the pin;
A power source for generating power for reciprocating the intermediate member,
A transmission belt pulley configured such that the pulley body can be reciprocated in the pulley axis direction together with the pivot so that the pulley body is positioned at two or more belt travel positions aligned in the pulley axis direction. The pulley according to claim 1, wherein
The pulley for a transmission belt, wherein the tilt angle of the pivot is set in an angle range exceeding 0 degrees and not exceeding 90 degrees. A pulley for a transmission belt according to claim 1 or 2 ,
A driving pulley,
A driven pulley,
A transmission belt wound between the driving pulley and the driven pulley,
A belt transmission device in which the transmission belt pulley is pressed to apply tension to the transmission belt. The belt transmission device according to claim 3 ,
One of the driving side pulley and the driven side pulley is a belt transmission device including a first pulley and a second pulley that are arranged in parallel in the rotation axis direction and have substantially the same outer peripheral surface. . The belt transmission device according to claim 3 ,
The transmission belt is a flat belt and is wound around the driving pulley at a contact angle larger than 180 degrees. A crank pulley fixed integrally with the engine crankshaft;
An accessory driving pulley including first and second pulleys attached to the rotating shaft of the accessory and arranged in parallel in the rotating shaft direction;
A transmission belt wound between the crank pulley and the accessory drive pulley;
A pulley body for transmission belt, comprising: a pulley body around which the transmission belt is wound; and a support means for supporting the pulley body so as to be rotatable about a pulley axis and swingable about a predetermined pivot axis. ,
The pivot shaft of the transmission belt pulley tilts at a predetermined tilt angle to the front side in the rotational direction of the pulley body with respect to the axial load direction when viewed along the pulley shaft direction.
The support means is configured to reciprocate the pulley body together with the pivot in the pulley axis direction, and a vacuum cylinder that moves the pulley body together with the pivot in the pulley axis direction by suction negative pressure of the engine. Have
An auxiliary engine drive system for an engine, further comprising a tank that is interposed between the engine and a vacuum cylinder and stores a suction negative pressure of the engine.

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