JP5489816B2 - Belt-type power transmission device for internal combustion engine - Google Patents

Description

  The present invention relates to a belt-type power transmission device used in an internal combustion engine when, for example, an auxiliary machine is driven by a crankshaft.

  An auxiliary machine such as an alternator and pumps is attached to the internal combustion engine, and these auxiliary machines are often driven by a crankshaft via a pulley and a belt (see, for example, Patent Document 1). The driving by the belt has an advantage that a plurality of shafts can be rotated in the same direction and an advantage that the cost can be suppressed, and has been used for a long time in an internal combustion engine.

  In addition, it is generally efficient that the auxiliary machine is driven at a higher rotational speed than the crankshaft rotational speed. Therefore, when the auxiliary machine is driven by a belt, the auxiliary pulley is more than the crankshaft pulley. By making the diameter small, the rotational speed of the auxiliary machine is set to be higher than the rotational speed of the crankshaft. Moreover, in a belt type power transmission device, a tensioner mechanism is often provided in order to absorb belt elongation and ensure a certain tension.

JP 2009-180177 A

  The belt-type power transmission device transmits power by using friction between the belt and the pulley. However, since the belt circulates while deforming, if the outer diameter is small like the pulley of the auxiliary machine However, there is a problem that the deformation of the belt becomes excessively large and heat loss occurs or deterioration is accelerated. This problem becomes more pronounced as the belt becomes thicker, such as a V-belt, and as the rotational speed increases.

  More specifically, since the outer diameter of the auxiliary pulley is small, the idle pulley is used to increase the contact length between the auxiliary pulley and the belt to ensure transmission (to prevent slipping). It is also widely practiced that the belt is wound around the auxiliary pulley by winding it from the outside of the loop. However, if the belt is wound around the U-turn in this way, the belt will be bent and deformed. Since the degree increases, the above-described problems of heat generation and early deterioration become more prominent.

  The present invention has been made in view of such a current situation, and intends to provide a power transmission device having excellent belt durability and the like.

  The invention of the present application relates to a power transmission device in an internal combustion engine having a plurality of rotating shafts and a belt for interlocking rotation of the rotating shafts, and the invention of claim 1 relates to at least one rotating shaft of the plurality of rotating shafts. An annular rotating body is provided, and a ring-shaped idler pulley around which the belt is wound is disposed on the outer periphery of the annular body so that the annular body is rotated by the rotation of the ring-shaped idler pulley. Touching.

The tensioner for imparting tension to hold electrolyte previous SL belts the ring idler pulley to the state inscribed in the wheel body is provided. The tensioner can employ various mechanisms. As an example, for example, as a configuration having a roller inscribed in a ring-shaped idle pulley and a link body to which the roller is rotatably attached, the link is rotatable, and the ring-shaped idle pulley is always configured by a roller. A configuration in which the link is biased by a spring so as to be pushed can be employed. Alternatively, the ring-shaped idler pulley can be configured to be biased by a spring in a certain direction.

  According to the present invention, for example, even when a small-diameter pulley is conventionally used, such as a drive shaft of an auxiliary machine, for example, the outer diameter of a ring is set to the same level as a conventional pulley. By making the ring-shaped idle pulley inscribed, the ring body can be rotated via the ring-shaped idle pulley. That is, the ring body is driven by the belt through the ring-shaped idle pulley. Since the ring-shaped idle pulley is inscribed in the ring body, the ring-shaped idle pulley is naturally larger in diameter than the ring body, and therefore, the ring body is operated at a high speed while suppressing deformation of the belt. Can be driven by rotation.

  As described above, in the present invention, even when a small-diameter pulley is conventionally used, by using the ring-shaped idle pulley, the shaft can be rotated to a desired rotational speed while greatly suppressing the deformation of the belt. Therefore, power loss and heat generation due to deformation of the belt can be remarkably suppressed and durability can be remarkably improved without impairing the power transmission function.

Furthermore, in the present invention, the slack of the belt can be absorbed by the tensioner, but since the tension is applied to the belt using the movement of the ring-shaped idle pulley, the deformation of the belt increases as the tension is applied. There is no problem, and therefore, an appropriate tensioner can always be applied to the belt without impairing the advantages of greatly suppressing power loss and heat generation and improving durability.

  Now, the alternator has conventionally been used to apply tension to the belt by moving itself, but in the case of auxiliary equipment such as a water pump and balance shaft, it is held at a predetermined position on the engine body. Therefore, when driving these auxiliary machines with a belt, a tension pulley that comes into contact with the belt from the outside of the loop must be provided, and there is a problem that deformation of the belt becomes large.

On the other hand, in the present invention, since the belt is tensioned by moving the ring-shaped idle pulley itself, an auxiliary machine in which the rotating shaft is held at a predetermined position like a water pump or a balance shaft. The tension can be automatically applied to the transmission device for driving the belt without increasing the deformation of the belt. This is one of the advantages of the present invention .

1 is a front view of an internal combustion engine according to a first embodiment. FIG. 2 is a side view taken along the line II-II in FIG. 1. (A) is a sectional view taken along line IIIA-IIIA in FIG. 1, and (B) is a sectional view taken along line IIIB-IIIB in FIG. It is a typical front view of a 2nd embodiment. It is a figure which shows 3rd Embodiment, (A) is a principal part front view, (B) is BB sectional drawing of (A). It is a partially broken principal part front view of 4th Embodiment. It is a figure which shows 5th-6th embodiment. It is a schematic diagram of 7th-8th embodiment.

  Next, an embodiment of the present invention will be described with reference to the drawings. Description will be made sequentially from the first embodiment.

(1) First Embodiment and Second Embodiment An internal combustion engine has an engine body (cylinder block) 1 having a cylinder bore and the like. From one surface 1a of the engine body 1, a crankshaft 2 and a water pump drive shaft are provided. 3 protrudes. A crank pulley 4 is fixed to the crankshaft 2, while a water pump pulley 5 is fixed to the water pump drive shaft 3, and a belt 7 is wound around them.

  An alternator 8 is fixed to the engine body 1, and the alternator 8 is also driven by the belt 7 by the crankshaft 2. That is, the alternator 8 is fixed to the back surface (the surface opposite to the belt 7) of the rib plate 1b provided on the engine body 1 with a bolt, and the rotating shaft 9 of the alternator 8 is projected from the rib plate 1b to the front side. The ring body 10 is fixed to the rotary shaft 9, and the belt 7 is wound around a ring-shaped idle pulley 11 inscribed in the ring body 10.

  A tension roller 12 constituting an auto tensioner is rotatably abutted (inscribed) on a portion of the inner peripheral surface of the ring-shaped idle pulley 11 positioned above the rotation shaft 9 of the alternator 8. The tension roller 12 is rotatably attached to an upper end of a link 13 disposed so as to extend in the vertical direction along the surface of the rib plate 1b in the engine body 1 by a shaft 13a and a bearing.

  The link 13 is connected (pivoted) to the rib 1b of the engine body 1 with a pin 14 extending in parallel with the rotary shaft 9 so as to rotate about a midway between its upper and lower ends. Further, one end of a spring (tensile spring) 15 for rotating the link 13 is connected to the lower end of the link 13 so that the tension roller 12 is urged in a direction to contact the ring-shaped idler pulley 11. . The other end of the spring 15 is locked to the engine body 1.

  As shown in FIG. 3, the belt 7 is a multiple V-belt in which a plurality of (four) strips 17 having a trapezoidal cross section are arranged side by side. For this reason, the crank pulley 4, the water pump pulley 5, and the ring shape. On the outer peripheral surface with the idler pulley 11, a plurality of (four) outer peripheral ridges 18 are formed corresponding to the grooves 17 of the belt 7. Further, the inner peripheral surface of the ring-shaped idle pulley 11 is formed in an uneven shape by forming a plurality of inner peripheral groove strips 19 in an annular shape, while the outer peripheral surface of the ring body 10 and the tension roller 12 is also a ring. A plurality of engaging ridges 20 that fit into the inner circumferential groove 19 of the idle pulley 11 are formed to have an uneven shape.

  The ridges and the grooves are relative concepts, the inner circumferential ridges are formed on the ring-shaped idle pulley 11, and the engagement grooves are formed on the ring body 10 and the tension roller 12. It can also be expressed as Eventually, the inner peripheral surface of the ring-shaped idler pulley 11 and the outer peripheral surface of the ring body 10 and the tension roller 12 have a fitting portion that fits in an axially displaceable manner without inhibiting mutual rotation. It can be generalized.

  In the above configuration, when the relationship between the crankshaft 2 and the alternator 8 is viewed, the rotation of the crankshaft 2 is transmitted from the belt 7 to the ring body 10 via the ring-shaped idler pulley 11, thereby the alternator 8. Is driven. The ring-shaped idle pulley 11 rotates in the circumferential direction of the belt 7, and the ring body 10 rotates in the same direction as the ring-shaped idle pulley 11. Accordingly, the ring body 10 of the alternator 8 rotates in the same direction as when the belt 7 is directly wound. The ring body 10 is set to have the same diameter as that of the conventional pulley, and therefore the rotating shaft 9 of the alternator 8 rotates at the same speed as in the conventional case.

  Since the ring-shaped idle pulley 11 is much larger in diameter than the ring body 10, the deformation of the belt 7 is remarkably suppressed as compared with the prior art. Resistance can be suppressed and durability is also greatly improved.

  The tension roller 12 is biased by a spring 15 in the direction of moving to the outside of the engine body 1 on the upper side of the ring body 10. Accordingly, the ring-shaped idler pulley 11 is also urged away from the engine body 1. For this reason, the belt 7 is always held in a tensioned state. When the tension roller 12 is moved to the inside of the engine body 1 against the spring 15, the ring-shaped idle pulley 11 can be brought close to the crank pulley 4 and the water pump pulley 5. For this reason, attachment (winding) and removal of the belt 7 can be easily performed.

  In addition, when the ring-shaped idle pulley 11 and the ring body 10 and the tension roller 12 are fitted so as not to be displaced as in this embodiment, the ring-shaped idle pulley 11 is free to move around the ring body 10. Therefore, there is an advantage that tension can be applied to the belt 7 while maintaining the state in which the ring-shaped idle pulley 11 is firmly pressed against the ring body 10 by the belt 7.

  In the second embodiment shown in FIG. 4, the tension roller 12 is disposed below the axis of the ring body 10, and is biased by the spring 15 in an obliquely downward direction away from the ring body 10. Also in this embodiment, since the ring-shaped idle pulley 11 is urged to the outside (lower side) of the engine body 1 by the tension roller 12, a tension is automatically applied to the belt 7.

  When the tension roller 12 is brought into contact with the inner peripheral surface of the ring-shaped idle pulley 11, the tension roller 12 can be disposed either above or below the axial center of the ring body 10 as can be understood from both the above embodiments. For this reason, the position of the tension roller 12 can be set according to the shape of the engine main body 1 and the attachment state of various members, and as a result, the freedom of design is high. Further, since the tension roller 12 and the link 13 do not get in the way when the belt 7 is attached / detached, the assemblability and the maintenance are excellent.

(2). Third to Fourth Embodiments In the above-described embodiments, the tension roller 12 is used as an auto tensioner mechanism. However, the belt 7 is tensioned by directly energizing the ring-shaped idle pulley 11. Can also be given. The example is shown as 3rd Embodiment and 4th Embodiment in FIG. 5, FIG.

  Of these, in the third embodiment shown in FIG. 5, an outer plate 11a covering the ring body 10 is provided on the outer end surface of the ring-shaped idler pulley 11, and a central shaft 22 provided on the outer plate 11a is provided with a bearing 23 therebetween. A slider 24 is attached, and the slider 24 is slidably attached to the guide rail 25. The guide rail 25 has an arc shape concentric with the rotating shaft 9 of the alternator, and is fixed to the engine body 1 via bracket means (not shown). The slider 14 is pulled downward and biased by a spring 15.

  In the third case, the ring-shaped idle pulley 11 is held in a stable posture by the guide rail 25 and the slider 14, and the slider 14 moves so that the ring-shaped idle pulley 11 is firmly attached to the ring body 10. It can be held in a pressed state and in a state where a tension is applied to the belt 7. The outer plate 11a only needs to have a function of holding the ring-shaped idle pulley 11 so as to be rotatable with respect to the slider 14. Therefore, it may be a rod-like form such as a trident.

  In the fourth embodiment shown in FIG. 6, the ring-shaped idler pulley 11 has an outer plate 11a as in the third embodiment. In this embodiment, a support shaft 26 parallel to the rotation shaft 9 is projected from a portion of the engine body 1 inside the ring body 10, and a slide guide 27 is rotatably attached to the support shaft 26. A rod 28 extending in a direction orthogonal to the rotation shaft 9 is mounted on the guide 27 so as to slide in the longitudinal direction, and the central shaft 23 of the ring-shaped idler pulley 11 can be freely rotated by a bush 29 provided at one end of the rod 28. Further, the rod 28 is urged by the spring 15 toward the outside of the engine body 1.

  In this embodiment, the ring-shaped idle pulley 11 is stably held by the rod 28 in a posture in which the axis is parallel to the axis of the ring body 10, and the rod 28 slides in the axial direction. The ring-shaped idler pulley 11 can be pushed toward the outside of the engine body 1 because it is freely movable and rotatable. The tensioner mechanisms of the first and second embodiments can be provided in the embodiment of FIGS.

(3). Fifth to Sixth Embodiments Since the ring body 10 is driven by the ring-shaped idle pulley 11, a strong frictional resistance is maintained between the ring-shaped idle pulley 11 and the ring body 10. It is necessary to keep. Therefore, in the fifth embodiment shown in FIG. 7A, the frictional resistance imparting material 30 is fixed or applied to the inner circumferential groove 19 of the ring-shaped idle pulley 11 and / or the engaging protrusion 20 of the ring body 10. I wear it. As the frictional resistance imparting material 30, for example, a rubber plate can be used.

  On the other hand, in the sixth embodiment shown in FIG. 7B, the lining 31 formed by cutting the belt 7 is fixed to the inner peripheral surface of the ring-shaped idle pulley 11, and the lining 31 is attached to the outer periphery of the ring body 10. A groove 32 to be fitted is formed. This embodiment has an advantage that a conventional pulley can be used as it is as the ring body 10. The lining 7 is fixed to the ring-shaped idler pulley 11 by screwing or bonding.

  When the belt 7 is cut to form the lining 31 as shown in FIG. 7B, the belt 7 is fixed to the inner peripheral surface of the ring-shaped idler pulley 11 in a state where one end and the other end of the lining 31 are abutted. In this case, it is possible to cut the end surface of the lining 31 directly to the side, but the cut surface (butting surface) 31a is inclined as shown in FIG. 7C, or the end surface is cut as shown in FIG. 7D. It is also possible to make the surface 31a mesh. 7C and 7D, there is an advantage that the ring body 10 smoothly moves the butted portion of the lining 31.

(4). Seventh to Eighth Embodiments / Others The present invention can be applied to a power transmission device that only transmits power from a main drive shaft to a driven shaft. An example is shown in FIG. Of these, in the seventh embodiment shown in FIG. 8A, a large-diameter pulley 35 is provided on one shaft 34, and a small-diameter ring body 10 is provided on the other shaft 36. 11 is inscribed. Further, in the eighth embodiment shown in FIG. 8B, the ring bodies 10 are provided on both the shafts 34 and 36, and the ring-shaped free pulley 11 is inscribed in both the ring bodies 10, so The belt 7 is wound around. Needless to say, an auto tensioner can be provided for these as well.

  The present invention can be embodied in various ways other than the above embodiment. For example, it can be applied to a power transmission device having four or more rotating shafts. The belt 7 may be a simple trapezoidal V-shaped belt, or a flat belt or a toothed timing belt may be used.

  The alternator is generally attached to a rotating bracket, and the belt tension is often adjusted by rotating the bracket (in other words, the alternator is often built into the auto tensioner). The present invention can also be applied to this type. That is, it is possible to provide a ring body on the rotating shaft of the alternator fixed to the rotary bracket, and to make the ring-shaped idle pulley inscribed in this ring body.

  The present invention is useful when applied to an internal combustion engine. Therefore, it can be used industrially.

DESCRIPTION OF SYMBOLS 1 Engine body 2 Crankshaft 3 Water pump drive shaft 4 Crank pulley 7 Belt 8 Alternator as an example of auxiliary machine 9 Alternator rotation shaft 10 Ring body received on alternator rotation shaft 11 Ring-shaped idler pulley 12 Constructs an auto tensioner Tension roller 13 Link constituting auto tensioner 15 Spring constituting auto tensioner

Claims (2)

And possess a belt for interlocking the rotation of these and a plurality of rotary shafts,
At least one rotation shaft of the plurality of rotation shafts is provided with a ring body that rotates integrally therewith, and a ring-shaped idler pulley around which the belt is wound around the outer periphery of the ring body is connected to the ring shape. a configuration wherein the wheel member by the rotation of the idler pulley that have to inscribed so as to rotate, imparting tension to the belt while maintaining the ring idler pulley to the state inscribed in the wheel body A tensioner is provided,
A belt-type power transmission device for an internal combustion engine. A tensioner that biases the ring-shaped idle pulley in a direction around the axis of the ring body while holding the ring-shaped idle pulley in a state inscribed in the ring body, and applies tension to the belt is provided.
The belt-type power transmission device for an internal combustion engine according to claim 1.

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