JP2011012790A - Transmission belt, power transmission mechanism including transmission belt and rotation body, and method of mounting transmission belt to rotation body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission belt maintaining sufficient tension even after mounted to rotation bodies.SOLUTION: The transmission belt 1 is mounted to be stretched between pulleys 8, 9 arranged spaced from each other, while being wound around them. The transmission 1 has a reference peripheral length shorter by 2.0-3.5% than the layout peripheral length of the pulleys 8, 9, and the tension in the peripheral length direction when the transmission belt 1 is mounted to the pulleys 8, 9 is 30-150 N/rib.

Description

  The present invention relates to a transmission belt, a power transmission mechanism including a transmission belt and a rotating body, and a method for mounting the transmission belt on the rotating body, which are applied to, for example, an accessory drive system for an automobile engine.

  As a power transmission belt, a belt having a relatively low elastic modulus (so-called low modulus belt) by using a polyamide fiber as a core wire is known (see Patent Document 1). The low modulus belt suppresses a sudden drop in tension compared to a high modulus belt (so-called high modulus belt), and the belt circumference is longer than the layout circumference of a rotating body such as a pulley to be mounted. It is said that there is an advantage that a tension adjusting mechanism such as an auto tensioner is not required by adopting this method because it is easy to adopt a method in which the belt is extended with a jig or the like while the belt is extended.

Special table 2004-532959 gazette

  By the way, the transmission belt needs to maintain sufficient tension even after being mounted on the rotating body in order to perform power transmission satisfactorily. After the drive of the power transmission mechanism including the transmission belt and the rotating body is started unless the tension in the circumferential direction of the transmission belt when mounted on the rotating body (hereinafter referred to as “the tension at the time of mounting the transmission belt”) is not more than a certain level. A problem may arise that the power transmission belt is stretched at an early stage, and power transmission cannot be performed reliably. In Patent Document 1, there is no proposal about the tension when the transmission belt is mounted, and this problem cannot be avoided.

  An object of the present invention is to provide a transmission belt capable of maintaining sufficient tension after being mounted on a rotating body, a power transmission mechanism including the transmission belt and the rotating body, and a method for mounting the transmission belt on the rotating body. It is.

  In order to achieve the above object, according to a first aspect of the present invention, an annular base portion, a core wire extending along a circumferential length direction of the base portion in the base portion, and the circumference of the base portion from the base portion, respectively. A plurality of ribs protruding in a direction intersecting the longitudinal direction and the width direction, extending along the circumferential direction, and arranged in parallel at intervals with respect to the width direction of the base portion; A transmission belt that can be extended and contracted in the longitudinal direction has a reference circumferential length that is 2.0 to 3.5% shorter than the layout circumferential length of two or more rotors that are spaced apart from each other and to which the transmission belt is attached. The transmission belt is characterized in that the tension in the circumferential direction when mounted on the rotating body is 30 to 150 N / rib.

  Here, the “layout circumference of the rotating body” refers to an annular shape along the outer circumference so as to connect the outer circumferences of the rotating bodies of two or more rotating bodies that are spaced apart from each other and to which the transmission belt is attached. The length of the formed line (that is, the path of the transmission belt). “Reference belt length of the transmission belt” means that the belt is wound around two flat pulleys (a rotating body having no groove on the outer peripheral surface) with the rib-formed surface outside. The length of the transmission belt in the circumferential direction when tension is applied to the transmission belt so as to remove the bending in the circumferential direction of the transmission belt.

  According to the said 1st viewpoint, sufficient tension | tensile_strength is maintainable after the mounting to a rotary body by setting the tension at the time of mounting | wearing of a transmission belt to 30-150 N / rib.

  The transmission belt according to the present invention has a permanent strain of 1.0 to 1.5% when a tensile force is applied to the transmission belt until the tension becomes 300 to 400 N / rib and then the tensile force is removed. It is preferable that If the permanent set is less than 1.0%, the maximum tension in the circumferential direction of the transmission belt is small and the elongation in the circumferential direction is small and does not reach the elongation at the time of wearing, as shown in the examples described later. Thus, it is difficult to mount the transmission belt on the rotating body (when mounting, the transmission belt needs to be extended 4.5% or more (preferably 4.5 to 6.0%) from the reference circumference). On the other hand, if the permanent strain exceeds 1.5%, the tension at the time of mounting the transmission belt may be less than 30 N / rib, as shown in Examples described later. In this case, it becomes difficult to maintain a sufficient tension of the transmission belt after being mounted on the rotating body, and slipping and sound generation may occur during the traveling of the transmission belt. Furthermore, when the permanent set exceeds 1.5%, as shown in the examples described later, the maximum tension in the circumferential direction of the transmission belt increases, so that a large force is required for mounting on the rotating body. For example, the mounting work becomes difficult, for example, a large stress is applied to the jig or the like and the jig is detached from the rotating body. Therefore, the above problems can be avoided by setting the permanent strain to 1.0 to 1.5%.

  In the power transmission belt according to the present invention, the core wire is preferably made of a polyamide fiber. In this case, as a low modulus belt, it is possible to obtain an effect of suppressing an abrupt drop in tension, and it is easy to adopt a method that does not require the tension adjusting mechanism as described above and that is easy to attach to the rotating body. The effect that can be obtained.

  In the power transmission belt according to the present invention, the core wire is preferably made of polyamide 6.6. In this case, the transmission belt can be made relatively inexpensive.

  The transmission belt according to the present invention may be applied to a drive system for an automobile engine. In this case, as described above, the tension adjusting mechanism is unnecessary, so that the weight of the engine can be reduced, and a fuel efficiency improvement effect is expected.

  According to a second aspect of the present invention, there is provided a power transmission mechanism comprising the transmission belt according to the first aspect and the two or more rotators mounted with the transmission belt.

  According to a third aspect of the present invention, an annular base portion, a core wire extending along the circumferential length direction of the base portion in the base portion, and the circumferential direction and the width direction of the base portion from the base portion, respectively. And a plurality of ribs extending in the circumferential direction and extending in the circumferential direction and arranged in parallel with each other with respect to the width direction of the base, and capable of expanding and contracting in the circumferential direction In a method of attaching a belt to two or more rotating bodies that are spaced apart from each other, an acquisition step of acquiring a layout perimeter of the rotating body, and a 2.0 for the layout perimeter acquired in the acquisition step A preparation step of preparing the transmission belt having a reference circumferential length that is 3.5% shorter, and the rotating belt that is prepared in the preparation step is attached to the rotating body while extending in the circumferential direction. And a mounting step of, in the mounting step, the method characterized by the tension of the circumferential length direction when mounted the transmission belt to the rotary member and 30～150N / ribs is provided.

  According to the second and third aspects, as in the first aspect, an effect that a sufficient tension can be maintained even after mounting on the rotating body is obtained, and power transmission can be performed satisfactorily.

It is sectional drawing which shows the power transmission belt which concerns on one Embodiment of this invention. It is a perspective view which shows the power transmission mechanism which concerns on one Embodiment of this invention. It is a perspective view which shows an example of the mounting step in the mounting method to the pulley of the transmission belt shown in FIG. FIG. 4 is a perspective view showing a state where one pulley is rotated approximately 110 ° from the state of FIG. 3. FIG. 5 is a perspective view showing a state where one pulley is further rotated by approximately 10 ° from the state of FIG. 4. It is a graph which shows the result of the 1st tensile test of a transmission belt in the Example of this invention. It is a graph which shows the result of the 2nd tensile test of a transmission belt in the Example of this invention. It is a graph which shows the result of the 3rd tensile test of a transmission belt in the Example of this invention. It is a table | surface which shows the result of the mounting | wearing property and slip test of a transmission belt in the Example of this invention.

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

  First, with reference to FIG. 1, the structure of the transmission belt 1 which concerns on one Embodiment of this invention is demonstrated.

  As shown in FIG. 1, the transmission belt 1 of the present embodiment includes an annular base 2 (see FIG. 2), a plurality of core wires 3 extending along the circumferential direction of the base 2 in the base 2, and the base 2. 4 ribs 4 protruding from one surface (that is, one of the front surface and the back surface along the circumferential direction and the width direction of the base 2 and the lower surface in FIG. 1), and the other surface of the base 2 ( This is a so-called V-rib belt having an extending portion 5 that covers the upper surface in FIG. The core wires 3 are arranged in parallel at predetermined intervals with respect to the width direction of the base portion 2 and are buried in the base portion 2. Each of the ribs 4 protrudes from one surface of the base portion 2 in a direction perpendicular to the surface (downward in FIG. 1), extends along the circumferential direction of the base portion 2, and forms a predetermined interval with respect to the width direction of the base portion 2. Are arranged in parallel. The transmission belt 1 can be expanded and contracted in the circumferential direction.

  The rib 4 is made of an elastic material such as a rubber composition. Examples of the rubber composition include natural rubber, butyl rubber, styrene-butadiene rubber, chloroprene rubber, alkylated chlorosulfonated polyethylene rubber, hydrogenated nitrile rubber, mixed polymer of hydrogenated nitrile rubber and unsaturated carboxylic acid metal salt, ethylene -Α-olefin rubber or the like, or a mixture thereof may be used. Examples of ethylene-α-olefin rubbers include copolymers of ethylene and α-olefins (propylene, butene, hexene, octene, etc.), copolymers of ethylene, α-olefins, and non-conjugated dienes. Specific examples include ethylene-propylene rubber (EPR) and ethylene-propylene-diene copolymer (EPDM). Examples of the non-conjugated diene include non-conjugated dienes having 5 to 15 carbon atoms such as ethylidene norbornene, dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, and methylene norbornene. EPDM is excellent in heat resistance and cold resistance, and by using EPDM as the material of the rib 4, the heat resistance and cold resistance of the transmission belt 1 can be improved. Further, among EPDM, those having an iodine value of 3 to 40 are preferable. This is because when the iodine value is less than 3, the rubber composition is insufficiently vulcanized, and the problem of wear and adhesion tends to occur. When the iodine value exceeds 40, the scorch of the rubber composition is shortened and handled. This is because it becomes difficult and heat resistance deteriorates.

  Moreover, the rib 4 can improve side pressure resistance by mixing the short fiber which consists of polyamide 6, polyamide 6.6, polyester, cotton, an aramid, etc. Further, the short fiber is provided on the surface of the rib 4 that contacts the pulleys 8 and 9 (see FIG. 2) so as to protrude from the surface, thereby reducing the friction coefficient of the rib 4 and driving the transmission belt 1. Noise can be suppressed. As the aramid fiber, those having an aromatic ring in the molecular structure (for example, trade name Conex, Nomex, Kevlar, Technora, Twaron, etc.) are preferable.

  The base 2 may be formed from the same rubber composition as the rib 4. However, in order to improve the adhesiveness with the core wire 3, it is not necessary to mix the short fiber as described above into the base portion 2.

  The core 3 is made of polyamide fiber (for example, polyamide 6.6, polyamide 4.6, etc., more preferably polyamide 6.6), and for example, a filament group of 800 to 1200 dtex is twisted 8 to 13 times / This is a twisted yarn cord having a total fineness of 4800 to 7200 dtex, which was twisted at 10 cm and a number of twists of 15 to 30 times / 10 cm.

  The elongated portion 5 is made of an appropriate material that can be expanded and contracted in the circumferential direction, and may be formed of, for example, only a rubber composition similar to the rib 4. Or you may form the expansion | extension part 5 with a textile fabric, a knitted fabric, a nonwoven fabric, etc.

  Next, a configuration of the power transmission mechanism 10 according to an embodiment of the present invention and a method for attaching the transmission belt 1 to the pulleys 8 and 9 will be described with reference to FIG.

  The power transmission mechanism 10 is applied to, for example, an auxiliary drive system for an automobile engine, and includes the transmission belt 1 of FIG. 1 and two pulleys 8 and 9 having the same diameter. The shafts of the pulleys 8 and 9 are fixed, that is, the distance between these shafts cannot be changed. On the outer peripheral surfaces of the pulleys 8 and 9, a plurality of grooves along the circumferential direction that can be engaged with the ribs 4 of the transmission belt 1 are formed. The transmission belt 1 is mounted on the pulleys 8 and 9 so that the rib 4 is on the inner side and the extension part 5 is on the outer side and is wound around the pulleys 8 and 9 so as to be bridged between them.

  One pulley 8 is a drive pulley connected to an engine output shaft (reciprocating engine crankshaft, rotary engine eccentric shaft, etc.), and the other pulley 9 is used for various auxiliary machines (water pump, alternator, etc.). A driven pulley attached to a connected driven shaft. When the drive pulley 8 is rotated by the torque of the output shaft, the transmission belt 1 travels with the rotation of the drive pulley 8. The auxiliary pulley 9 rotates as the transmission belt 1 travels, so that various auxiliary machines are driven.

  One pulley 8 has a two-stage configuration and includes two pulleys 8a and 8b stacked in the axial direction. Each pulley 8a, 8b has the same size and shape as the other pulley 9. These pulleys 8a and 8b are integrated, and rotate together when the power transmission mechanism 1 is driven. The axial lengths of the pulleys 8 a, 8 b, 9 are substantially the same as the width of the transmission belt 1, and the transmission belt 1 is wound around the lower pulley 8 b of one pulley 8 and the other pulley 9.

  The transmission belt 1 is attached to the pulleys 8 and 9 by, for example, the following method.

  First, the layout circumference Lp of the pulleys 8 and 9 is acquired (acquisition step). The “layout circumferential length Lp of the pulleys 8, 9” means along the outer circumference so as to connect the outer circumferences of the pulleys 8, 9 in the pulleys 8, 9 that are spaced apart from each other and to which the transmission belt 1 is attached. It refers to the length of a ring-shaped line (that is, the path of the transmission belt 1). In the present embodiment, since the pulleys 8 and 9 have the same diameter and the transmission belt 1 extends in parallel between the pulleys 8 and 9, the semicircular circumference of each pulley 8 and 9 and the axis between the pulleys 8 and 9. It is roughly calculated by the sum of twice the distance. The layout circumference Lp may be acquired by calculation or may be acquired by actual measurement or the like.

  Next, the transmission belt 1 having a reference circumferential length Lb that is 2.0 to 3.5% shorter than the layout circumferential length Lp acquired in the acquisition step is prepared (preparation step). “The reference circumferential length Lb of the transmission belt” refers to the transmission belt 1 having two flat pulleys (a rotating body having no groove formed on the outer circumferential surface thereof, with the surface on which the ribs 4 are formed facing outward. The fixed pulley and the moving pulley used in the example are mounted so as to be wound between them, and tension is applied to the transmission belt 1 so as to remove the bending in the circumferential direction of the transmission belt 1. This is the length of the transmission belt 1 in the circumferential direction. Further, “the reference circumference Lb is 2.0 to 3.5% shorter than the layout circumference Lp” means that the reference circumference Lb is 2.0 to 3.5% of the reference circumference Lb. Means that the layout circumference is equal to the layout circumference Lp.

  Next, the transmission belt 1 prepared in the preparation step is attached to the pulleys 8 and 9 while extending in the circumferential direction (attachment step).

  The mounting step may be performed using a jig 50 as shown in FIGS. That is, first, as shown in FIG. 3, the connecting portion 60a of the wrench 60 is fixed to the boss 8c of one pulley 8, and the bending portion 51 having a curved shape along the outer periphery of the pulley 8 in the jig 50 is replaced with the upper pulley 8a. The jig 50 is arranged so that the line connecting the shafts 8x and 9x of the pulleys 8 and 9 and the line connecting the shaft 8x and the jig 50 are substantially perpendicular to each other in the plan view. Then, the transmission belt 1 is inserted between the curved portion 51 and the projecting portion 52 of the jig 50 and brought into contact with the guide 53, and is passed over the other pulley 9 and the connecting portion 60 of the wrench 60. The guide 53 is formed by rounding the corner of the jig 50 on the main body 50a (the lower end of the surface from which the protrusion 52 protrudes in FIG. 3). The transmission belt 1 is bent by a guide 53, and a portion below the guide 53 is disposed along the outer periphery of the lower pulley 8b.

  Thereafter, while fixing the jig 50 to the upper pulley 8a, the pulley 8 is rotated approximately 110 ° in the A direction by using a wrench 60 (see FIG. 4). At this time, the upper and lower pulleys 8a and 8b rotate together, and the jig 50 fixed to the upper pulley 8a also rotates about 110 ° in the A direction with respect to the shaft 8x. Further, during this rotation, a tensile force in the circumferential direction is gradually applied to the transmission belt 1, and at this time, the tension generated in the transmission belt 1 acts to press the jig 50 against the upper pulley 8a. In the state of FIG. 4, the transmission belt 1 is separated from the connecting portion 60 a of the wrench 60, and a portion corresponding to the rotation trajectory of the jig 50 in the transmission belt 1 is wound around the lower pulley 8 b.

  Thereafter, when the pulley 8 is further rotated approximately 10 ° in the direction A using the wrench 60 from the state shown in FIG. 4, the elastic energy stored by the tensile force is minimized in the transmission belt 1 as shown in FIG. 5. As described above, the jig 50 moves downward from between the curved portion 51 and the protruding portion 52, is separated from the jig 50 and the upper pulley 8a, and is wound around the lower pulley 8b. Thereafter, the jig 50 is collected.

  In the mounting step as described above, the tension in the circumferential direction when the transmission belt 1 is mounted on the pulleys 8 and 9 (the tension when the transmission belt 1 is mounted) is set to 30 to 150 N / rib. The transmission belt 1 mounted according to the mounting method of the present embodiment has a circumference extending 2.0 to 3.5% from the reference circumferential length, and has a tension of 30 to 150 N / rib in the circumferential direction. The pulleys 8 and 9 are mounted.

  As described above, according to the transmission belt 1, the power transmission mechanism 10, and the method of mounting the transmission belt 1 to the pulleys 8 and 9 according to this embodiment, the tension at the time of mounting the transmission belt 1 is 30 to 150 N / rib. Thus, sufficient tension of the transmission belt 1 can be maintained even after the pulleys 8 and 9 are mounted.

  Specifically, when the tension at the time of mounting the transmission belt 1 is less than 30 N / rib, the transmission belt 1 tends to extend in the circumferential direction as shown in the examples described later, and after the mounting to the pulleys 8 and 9. It becomes difficult to maintain sufficient tension of the transmission belt 1. Furthermore, when the number of rotations of the pulleys 8 and 9 is constant (5000 rpm in the examples described later) or more, the contact area between the transmission belt 1 and the pulleys 8 and 9 becomes small due to the influence of centrifugal force. Between the pulleys 8 and 9 and the pulleys 8 and 9, and thus sound may occur. On the other hand, if the tension at the time of mounting the transmission belt 1 exceeds 150 N / rib, it is difficult to mount the transmission belt 1 (for example, when the tension at the time of mounting the transmission belt 1 is 160 / rib, a peak torque of 45 to 60 Nm is generated. In addition, it may become impossible to install depending on the manual work, and a large load is applied to the pulleys 8 and 9 and the shafts attached to the pulleys 8 and 9 to be mounted. Problems with durability can also arise. Therefore, by setting the tension at the time of mounting the transmission belt 1 to 30 to 150 N / rib, it is possible to avoid the inconveniences as described above and to maintain a sufficient tension of the transmission belt 1 even after mounting on the pulleys 8 and 9. it can.

  Further, the reference circumferential length Lb of the transmission belt 1 is shortened by 2.0 to 3.5% with respect to the layout circumferential length Lp of the pulleys 8 and 9, so that the mounting method to the pulleys 8 and 9 is as described above. A method of attaching the transmission belt 1 to the pulleys 8 and 9 while extending, that is, a method that does not require a tension adjusting mechanism and is easy to install can be employed.

  As shown in the examples described later, the transmission belt 1 has a permanent strain of 1. after applying a tensile force until the circumferential tension becomes 300 to 400 N / rib, and then removing the tensile force. It is preferable that it is 0 to 1.5%. When the permanent set is less than 1.0%, the maximum tension in the circumferential direction of the transmission belt 1 is small and the elongation in the circumferential direction is small and does not reach the elongation at the time of wearing, as will be shown in Examples described later. For this reason, it becomes difficult to mount the transmission belt 1 on the pulleys 8 and 9 (when mounting, the transmission belt 1 is extended 4.5% or more (preferably 4.5 to 6.0%) from the reference circumferential length. There is a need). On the other hand, if the permanent strain exceeds 1.5%, the tension at the time of mounting the transmission belt 1 may be less than 30 N / rib, as shown in Examples described later. In this case, it becomes difficult to maintain a sufficient tension of the transmission belt 1 after being attached to the pulleys 8 and 9, and slipping and sound generation may occur during the traveling of the transmission belt 1. Further, when the permanent strain exceeds 1.5%, the maximum tension in the circumferential direction of the transmission belt 1 increases as shown in the examples described later, so that a large force is applied when the pulleys 8 and 9 are attached. For example, a large stress is applied to the jig 50 and the jig 50 is detached from the pulleys 8 and 9, making the mounting work difficult. Therefore, the above problems can be avoided by setting the permanent strain to 1.0 to 1.5%.

  Since the core 3 is made of polyamide fiber, the transmission belt 1 can be used as a low modulus belt to obtain an effect of suppressing a sudden drop in tension, and the tension adjusting mechanism as described above can be attached to the pulleys 8 and 9. The effect that it is easy to adopt a method that does not require and is easy to mount can be obtained.

  Furthermore, among polyamide fibers, when polyamide 6.6 is used for the core wire 3, the transmission belt 1 can be made relatively inexpensive.

  The transmission belt 1 is applied to an automobile engine drive system. In this case, as described above, the tension adjusting mechanism is unnecessary, so that the weight of the engine can be reduced, and a fuel efficiency improvement effect is expected.

  Next, the present invention will be specifically described with reference to examples.

  First, a transmission belt 1 as shown in FIG. 1 (corresponding to the inner surface of the base 2, the core wire 3 extends along the circumferential direction of the base 2 and at a predetermined interval in the width direction of the base 2. The transmission belt 1) in which the four ribs 4 protrude from the base portion 2 and the elongated portion 5 is formed on the other surface of the base portion 2 was manufactured as follows.

  That is, EPDM rubber composition mixed with short fibers (EPDM 100 parts by weight, nylon 6.6 short fibers 10 parts by weight, ZnO 3.5 parts by weight, stearic acid 1.0 parts by weight, carbon black 65 parts by weight, anti-aging agent A first sheet (elongated part 5) comprising 2.0 parts by weight, 5.0 parts by weight of paraffin oil, 2.0 parts by weight of a co-crosslinking agent, 2.0 parts by weight of an organic peroxide, and 0.15 parts by weight of sulfur. And a second sheet made of the same EPDM rubber composition that does not contain short fibers (sheet serving as the base 2), and the laminate is formed into a cylindrical mold with the first sheet inside. I wound it. Then, an EPDM rubber composition in which a core wire 3 produced as described below is spun on the second outer sheet at a pitch of 1.10 mm, and short fibers similar to those in the first sheet are mixed thereon. The 3rd sheet | seat (sheet | seat used as the rib 4) which consists of was wound, and it shape | molded. The molded body was vulcanized by an appropriate method under conditions such as a temperature of 160 ° C. and a time of 30 minutes to obtain an annular vulcanized rubber sleeve. After that, the vulcanized rubber sleeve is mounted on the driving roll and driven roll of the polishing machine and traveled while applying tension, and a polishing wheel provided with 150 mesh diamond is applied to the surface of the sleeve (that is, the first roll). The surface of the third sheet was rotated at 1600 rpm in the direction opposite to the traveling direction of the sleeve while being in contact with the surface of the third sheet, whereby the surface of the third sheet was partially polished to form the ribs 4. Then, the sleeve on which the ribs 4 are formed is taken out from the polishing machine, installed in a cutting machine, and cut to a predetermined length in the width direction while rotating, and the rib pitch is 3.56 mm, the rib height is 2.9 mm, and the rib angle is 40. A transmission belt 1 having a reference circumferential length of 816 mm was obtained.

  In addition, the manufacturing method of the core wire 3 is as follows. That is, a twisted yarn cord (polyamide 6.6, composition 940 dtex / 2 × 3, twisted, total fineness 5640 dtex) is made of an adhesive composed of 90% by weight of toluene and 10% by weight of PAPI (polyisocyanate compound manufactured by Kasei Upjohn). Pre-dip and dried for 2 minutes at 200 ° C. in a drying oven. Then, the cord after the drying treatment was impregnated with an adhesive made of an RFL solution, and further subjected to heat treatment at 230 ° C. for 2 minutes, and then heat stretched and fixed at a heat set stretching ratio of 3.8%. And the cord 3 was obtained by immersing the cord in rubber paste (a rubber composition containing EPDM blended so as to have a solid content concentration of 10%), followed by heat treatment at 160 ° C. for 4 minutes.

  Using the transmission belt 1 manufactured as described above, a tensile test and a wearability / slip test were performed.

  In the tensile test, the transmission belt 1 is mounted on two flat pulleys (not shown) of a fixed pulley and a moving pulley with the surface on which the rib 4 is formed facing outward, and the movement of the moving pulley is controlled. When the transmission belt 1 is pulled in the circumferential direction at a speed of 50 mm / min and a tensile force in the circumferential direction is gradually applied to the transmission belt 1, the tension in the circumferential direction of the transmission belt 1 reaches a predetermined value. Thus, the tensile force applied to the transmission belt 1 was removed.

  FIG. 6 shows a hysteresis curve obtained by repeating the above-described series of operations for adding and removing the tensile force three times (first tensile test) with the predetermined value being 300 N / rib. FIG. 7 shows a hysteresis curve obtained by performing the above-described series of operations for adding and removing the tensile force once (second tensile test) with the predetermined values being 200, 300, and 375 N / rib. FIG. 8 shows a hysteresis curve obtained by repeating the above-described series of operations for adding and removing the tensile force three times (third tensile test) with the predetermined value being 500 N / rib. 6 to 8, the vertical axis represents the tension in the circumferential direction of the transmission belt 1, and the horizontal axis represents the rate of change in the circumferential length of the transmission belt 1. The rate of change in the circumferential length means that the transmission belt 1 is tensioned to the extent that the bending in the circumferential direction is removed by attaching the transmission belt 1 to the two flat pulleys with the surface on which the ribs 4 are formed facing outward. When the length of the transmission belt in the circumferential direction when added is “reference circumferential length” (the rate of change at this time is 0%), and then the transmission belt 1 expands in the circumferential direction in accordance with the addition of tension. The ratio of the extended length to the reference circumference.

  In FIGS. 6 and 8, the curves indicated by (1), (2), and (3) are the hysteresis curves for the first, second, and third operations, respectively, and the hysteresis curves for the second and third times are approximately one. I'm doing it. In FIG. 7, curves indicated by (i), (ii), and (iii) are hysteresis curves corresponding to the predetermined values 200, 300, and 375 N / rib, respectively.

  In the first tensile test (see FIG. 6), the permanent strain generated by the first operation is slightly over 1.0%, and the permanent strain generated by the second and third operations thereafter is 1.0 to 1. It was within the range of 5%. In the second tensile test (see FIG. 7), the permanent strain is approximately 0.6% when the predetermined value is 200 N / rib (i), and the permanent strain is approximately 1 when the predetermined value is 300 N / rib (ii). In the case of 2% and the predetermined value of 375 N / rib (iii), the permanent set was approximately 1.3%. In the third tensile test (see FIG. 8), the permanent strain generated by the first operation is approximately 1.7%, and the permanent strain generated by the subsequent second and third operations is approximately 2.0%. there were.

  In the wearability / slip test, first, six types of transmission belts 1 having different tensions at the time of wearing are attached to the pulleys 8 and 9 when the transmission belt 1 is worn (whether the work can be easily carried out). It confirmed using. In mounting, the driving pulley 8 (diameter 133 mm) connected to the crankshaft and the driven pulley 9 (diameter) connected to the compressor using the jig 50 (see FIGS. 3 to 5) as in the above-described embodiment. 100 mm) and the transmission belt 1 was mounted. The layout peripheral length Lp of the pulleys 8 and 9 is 837 mm, and the reference peripheral length Lb (816 mm) of the transmission belt 1 is approximately 2.5% shorter than the layout peripheral length Lp. Thereafter, with the transmission belt 1 mounted on the pulleys 8 and 9, the pulley 8 is driven at a rotational speed of 750 to 5000 rpm, the transmission belt 1 is caused to travel, slip between the transmission belt 1 and the pulleys 8 and 9, and this The presence or absence of pronunciation was confirmed by the examiner's hearing.

  As can be seen from FIG. 9 (a table showing the results of the wearability / slip test), in the transmission belt 1 with the tension at the time of installation of 15, 30, 60, 100, 130 N / rib, the installation work is easy. The 160N / rib transmission belt 1 is difficult to install (specifically, a peak torque of 45 to 60 Nm is generated, which makes it difficult to install the transmission belt) Because the shaft attached to the pulley is also heavily loaded, there was concern about the durability of these pulleys and shafts). Regarding the presence or absence of slip and sound generation, in the transmission belt 1 having a tension of 15 N / rib at the time of installation, slip and sound generation were caused when the rotation speed of the pulley 8 was 5000 rpm. No. 30, 60, 100, 130, 160 N / rib), slip or the like did not occur even when the rotational speed of the pulley 8 exceeded 5000 rpm.

  The preferred embodiments and examples of the present invention have been described above. However, the present invention is not limited to the above-described embodiments and examples, and various design changes are possible as long as they are described in the claims. It is a thing.

  In the transmission belt according to the present invention, the core wire 3 is not limited to being made of a polyamide fiber such as polyamide 6.6. Moreover, you may abbreviate | omit the extending | stretching part 5, or may change the number of the core wires 3 and the number of the ribs 4 arbitrarily.

  In the power transmission mechanism according to the present invention, the number of rotating bodies is not limited to 2, but may be 3 or more, and the diameter of each rotating body and the layout thereof may be various.

  The power transmission mechanism according to the present invention is not limited to being applied to an auxiliary drive system for an automobile engine as in the above-described embodiment, and can be applied to other appropriate power transmission systems, such as windows and doors. The present invention is also applicable to a system that changes torque according to the opening / closing angle of an opening / closing member such as a lid.

  The mounting method of the transmission belt according to the present invention is applicable to various drive transmission systems as described above.

  The mounting of the transmission belt to the rotating body may be performed using various jigs other than the jig 50 of the above-described embodiment, or may be performed manually without using the jig.

DESCRIPTION OF SYMBOLS 1 Transmission belt 2 Base 3 Core wire 4 Rib 8, 9 Pulley (rotary body)
10 Power transmission mechanism

Claims (7)

An annular base;
A core wire extending along a circumferential direction of the base in the base;
A plurality of protrusions projecting from the base in a direction intersecting the circumferential direction and the width direction of the base, extending along the circumferential direction, and arranged in parallel at intervals with respect to the width direction of the base In the transmission belt comprising the ribs and extendable in the circumferential direction,
Having a reference circumference shorter by 2.0 to 3.5% than the layout circumference of two or more rotors that are spaced apart from each other and to which the transmission belt is attached;
The transmission belt, wherein the tension in the circumferential direction when mounted on the rotating body is 30 to 150 N / rib.   The permanent set produced when the tensile force is applied to the transmission belt until the tension becomes 300 to 400 N / rib and then the tensile force is removed is 1.0 to 1.5%. Item 2. The transmission belt according to Item 1.   The power transmission belt according to claim 1 or 2, wherein the core wire is made of polyamide fiber.   The transmission belt according to claim 3, wherein the polyamide fiber is polyamide 6.6.   The power transmission belt according to claim 1, wherein the power transmission belt is applied to a drive system for an automobile engine. The transmission belt according to claim 1,
A power transmission mechanism comprising: the two or more rotating bodies on which the transmission belts are mounted. An annular base, a core extending along the circumferential direction of the base within the base, and the circumferential length protruding from the base in a direction intersecting the circumferential direction and the width direction of the base. A plurality of transmission belts extending in the direction and extending and contracting in the circumferential direction, the ribs being spaced apart from each other, the ribs being arranged in parallel to each other in the width direction of the base; In the method of mounting on the above rotating body,
An acquisition step of acquiring a layout circumference of the rotating body;
A preparation step of preparing the transmission belt having a reference circumference shorter by 2.0 to 3.5% than the layout circumference obtained in the obtaining step;
A mounting step of mounting the transmission belt prepared in the preparation step on the rotating body while extending in the circumferential direction;
In the mounting step, the circumferential tension when the transmission belt is mounted on the rotating body is 30 to 150 N / rib.

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