JP4048536B2 - Belt power transmission device with automatic tension adjustment mechanism for bicycles - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a belt power transmission device with an automatic tension adjusting mechanism for a bicycle that automatically adjusts a belt tension in accordance with a pedaling force applied to a crank.
[0002]
[Prior art]
Conventionally, as disclosed in Japanese Patent Publication No. 7-54136, the present applicant has proposed a belt power transmission device with an automatic tension adjusting mechanism that automatically adjusts the belt tension according to the pedaling force applied to the crank. ing.
[0003]
[Problems to be solved by the invention]
As shown in FIG. 11, the Japanese Patent Publication No. 7-54136 proposed by the applicant of the present patent application has an annular driven wheel 31 having endless outer teeth 4 on its outer peripheral end surface, and a smaller diameter than the inner diameter of the annular driven wheel 31. The drive disk 35 integrally having a drive shaft 36 at the center located on the inner peripheral side of the annular driven wheel 31, and the drive shaft 36 of the drive disk 35 at the center on both side surfaces of the annular driven wheel 31. Both side plates 38, 38 that have windows 39, 39 to be penetrated and are integrally attached to the annular driven wheel 31 so as to cover both side surfaces of the annular driven wheel 31, and a side plate cover 41 outside the both side plates 38, 38. , 41 and a toothed belt (not shown) wound between the annular driven wheel 31 and a power-transmitted pulley (not shown), and the drive disk 35 is equidistant around the drive shaft 36. In addition, a plurality of bushes 37, 37 projecting in the lateral direction are provided, and both side plates 38, 38 are equidistant from the center and project on both side surfaces of the drive disk 35. Bush windows 40, 40 having an inner diameter larger than the diameter of the bushes 37, 37 are provided at positions corresponding to the bushes 37, 37, and the drive disk 35 is annularly driven wheels 31 in a state where the bushes 37, 37 are loosely fitted. The belt-type power transmission device is characterized by being loosely fitted on the inner circumference side of the motor, and evenly balanced to the left and right to provide excellent transmission characteristics. However, the structure is complex, the number of components is large, and the cost is high. Could not escape.
[0004]
The present invention eliminates the complexity of the structure, significantly reduces costs, and inherently has characteristics of belt drive devices such as maintenance-freeness, quietness, and light transmission. It is an object of the present invention to provide a device having an appearance with excellent design characteristics.
[0005]
[Means for Solving the Problems]
A belt power transmission device with an automatic tension adjusting mechanism for a bicycle comprising a crank disk , a crank pulley body that is loosely fitted to the crank disk, and a driven portion of the lid body that is engaged and supported. a crank disk body, to form a crank arm fixed integrally on its side, the crank disc body, the surface opposite to the mounting surface of the crank arm, the fixation portion axis concentric crank arm, and mutually equal intervals circumferentially column drive pin is required the number of collision set in the crank pulley body of the driven portion, the circumferential substrate portions formed on one side surface, thereby forming the outer diameter edge on one of the outer sealing rim A number of loose-fitting receiving holes corresponding to the circumferential row drive pins of the crank disk are formed on the inner side of the tooth portion that meshes the toothed belt on the inner surface side thereof. A support cylinder part that forms a body attachment hole between the bearing cylinder part and the lid body is provided so as to be raised, and a main body crankshaft loose-fitting hole for loosely fitting the crankshaft is provided at the center of the circumferential substrate part. lid is closely polymerizable to form on the inner surface of the crank pulley body, before SL in response to the same circumference which matches the body mounting hole of the crank pulley body Resshi form Naruhai the lid rectangular holes mounting hole, A seat is formed on the outer end of each lid body square hole mounting hole, and a square root formed on the back surface of the head of the mounting bolt is fitted and inserted into the lid square hole mounting hole. Is inserted into the main body mounting hole of the crank pulley main body, then reaches each nut hole communicating with the main body mounting hole, and the nut is screwed into each nut hole and tightened from both sides, and the crank pulley main body and the lid body And the lid of the driven part is between each lid square hole mounting hole. The surface is radially formed from the center lid crankshaft loose-fitting hole to the outer diameter edge in an inverted triangle shape, and each lid body square hole mounting hole is extended to the inner surface of the lid body. Alignment bosses that are bearing holes of the same axis are formed to protrude, and the inner surface of the crank pulley body, the inlet of each mounting hole, and a diameter larger than the mounting hole, fit with the positioning boss The boss insertion holes with the required diameter are formed concentrically to the required depth, respectively, and when the crank pulley body and the lid body are overlapped, the alignment boss and the boss insertion hole are fitted to each other so that their axes coincide with each other It is in the belt power transmission device with the automatic tension adjustment mechanism for bicycles comprised.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
A bicycle power transmission device with an automatic tension adjusting mechanism for a bicycle according to an embodiment of the present invention includes a crank disk 2 , a crank pulley body 3a that is loosely fitted to the crank disk 2 , and is engaged and supported, and a lid 3b. be one that is composed of the driven unit 3 which, the crank disk 2, the crank disk body 2a, to form a crank arm 2b to fix integrally with a side surface, the crank disc body 2a has a crank arm 2b the mounting surface and the opposite surface of the fixing portion axis concentric crank arm 2b, and mutually equally spaced circumferential array drive pin 4 is required the number of collision set in the crank pulley body 3a of the driven part 3 the circumferential substrate portions 3a1 formed on one side surface, thereby forming the outer diameter edge on one of the outer sealing rim 7, meshes with the toothed belt 8 on the inner surface side teeth 9, the body mounting hole 12 of the bushing portion 11 which forms a number of loosely receiving holes 10 corresponding to the circumferential row driving pin 4 of the crank disc 2 on the inner diameter side of the tooth portion 9, the lid 3b provided raised the support cylinder portion 13 which forms a, e Bei body crankshaft loosely fitted hole 15 loosely fitting the crankshaft 14 at the center of the circle periphery of the substrate portion 3a1, the lid body 3b of the driven unit 3, a crank closely polymerizable to form on the inner surface of the pulley body 3a, also Resshi body mounting hole 12 and form Naruhai the lid square hole mounting holes 18 in correspondence with the same circumference matching of the crank pulley body 3a, A receiving seat 19 is formed at the outer end of each lid body square hole mounting hole 18, and a square root portion 20 a 1 formed on the back surface of the head of the mounting bolt 20 is fitted and inserted into the lid square hole mounting hole 18. The tip of each is inserted into the body mounting hole 12 of the crank pulley body 3a. After that, the nut holes 121a communicating with the body mounting holes 12 are respectively reached, and the nuts 21 are screwed at the portions of the nut holes 12a and tightened from both sides, so that the crank pulley body 3a and the lid body 3b are integrally formed. Then, the lid 3b of the driven part has a raised decorative part that bulges the outer surface between each lid square hole mounting hole 18 from the center lid crankshaft loose fitting hole 23 to the outer diameter edge in an inverted triangular shape. 24 are formed radially, and alignment bosses 18a are formed on the inner surface of the lid 3b so as to extend the lid square hole mounting holes 18 to form bearing holes of the same axis, respectively, and the crank pulley A boss insertion hole 12b having a diameter larger than that of the mounting hole 12 and matching with the alignment boss 18a is formed concentrically at a required depth at the inner surface of the main body 3a and at the inlet of each mounting hole 12, respectively. Formed, polymerization of crank pulley body 3a and lid 3b A belt power transmission device with an automatic tension adjusting mechanism for a bicycle, which is configured so that the alignment boss 18a and the boss insertion hole 12b are sometimes fitted to each other so that their axes coincide with each other .
[0007]
【Example】
Hereinafter, a belt power transmission device with an automatic tension adjusting mechanism for a bicycle according to the present invention will be described with reference to the drawings as an example. Belt power transmission device 1 with an automatic tension adjusting mechanism for a bicycle shown in the drawings (hereinafter simply referred to as a belt power transmission device) 1) includes a crank disk 2, a crank pulley main body 3a that is loosely fitted to the crank disk 2, and is supported by engagement, and a driven portion 3 of the lid 3b.
[0008]
As shown in FIG. 6, the crank disk 2 is formed of a crank disk main body 2a and a crank arm 2b that is integrally fixed to the side surface thereof. The crank disk main body 2a is formed on the surface opposite to the mounting surface of the crank arm 2b. The required number of circumferential row drive pins 4, six in the embodiment, are provided so as to be concentric with the axis of the fixed portion of the crank arm 2 b and at equal intervals. In the embodiment, a collar 5 is fitted to each circumferential row drive pin 4. An elastic ring 6 having a diameter slightly larger than that of the collar 5 may be further fitted to the base end 4 a of each circumferential row drive pin 4.
[0009]
As shown in FIG. 7-a, the crank pulley main body 3a has a circumferential substrate portion 3a1 formed on one side surface, an outer diameter edge formed on one outer rim portion 7, and a tooth on the inner surface side. A bearing cylinder portion 11 that forms a number of loose fitting receiving holes 10 corresponding to the circumferential drive pins 4 of the crank disk 2 on the inner diameter side of the tooth portion 9 that meshes with the attached belt 8, and a lid The support cylinder part 13 which forms the main body attachment hole 12 with the body 3b is protrusively provided, and the main body crankshaft free fitting hole 15 for loosely fitting the crankshaft 14 is provided at the center of the circumferential substrate part 3a1. . The embodiment of the crank pulley main body 3a is molded from a synthetic resin material. As shown in FIG. 7B, a metal bush 16 may be inserted into each of the bearing tube portions 11 so as to be molded as a whole, and the inner surface thereof may be provided in the loose fitting receiving hole 10. Of course, the bush is not limited to metal. Depending on the molding material, the bush may not be required.
[0010]
In this embodiment, the lid body 3b is also formed of a synthetic resin material, and as shown in FIG. 8, a circumferential outer edge is formed on the other outer rim portion 17, and an inner diameter inner surface is formed on the crank pulley main body. 3a is formed so as to be able to be closely polymerized, and corresponding to the same circumference as the main body mounting hole 12 of the crank pulley main body 3a, a lid square hole mounting hole 18 is formed and arranged correspondingly, A receiving seat 19 is formed at the outer end of each lid body square hole mounting hole 18, and a square root portion 20 a 1 formed on the back surface of the head 20 a of the mounting bolt 20 is fitted into the lid square hole mounting hole 18. Then, after the respective tips are inserted into the main body mounting holes 12 of the crank pulley main body 3a, they reach the nut holes 12a communicating with the main body mounting holes 12, respectively, and the nuts 21 are screwed together at the nut holes 12a. And tighten from both sides. And Lee body 3a and the lid body 3b is intended to integrally configured. In advance, the circumferential drive pin 4 of the crank disk 2 is loosely fitted and engaged with the loose fitting receiving hole 10 of the crank pulley main body 3a, and the crank arm 2b is removed from the lid crankshaft loose fitting hole 23. Then, as described above, the crank pulley main body 3a and the lid 3b are tightened with the mounting bolt 20, and the crank arm 2b integrated with the crankshaft 14 is entirely tensioned within the clearance of the loose fitting receiving hole 10. Is adjustable and supported.
[0011]
The mounting bolt 20 is fitted with a washer 22 having a diameter larger than the outer diameter of the head 20a, and the outer surface of the lid 3b is doubled by the curved surface of the head 20a of the mounting bolt 20 and the flat surface of the washer 22. It can be reflected and decorated.
[0012]
The lid body 3b radially forms an outer surface between each lid body square hole mounting hole 18 from the center lid part crankshaft loose-fitting hole 23 to the outer diameter edge in an inverted triangular shape, While improving the rigidity and intensity | strength of the cover body 3b, the eye catcher function at the time of rotation is provided.
[0013]
Alignment bosses 18a are formed on the inner surface of the lid body 3b so as to extend the lid body square hole mounting holes 18 to form bearing holes of the same axis, respectively, and on the inner surface of the crank pulley body 3a, A boss insertion hole 12b having a diameter larger than that of the mounting hole 12 and matching with the positioning boss 18a is formed at the inlet of the mounting hole 12 so as to be concentric with the required depth, and the lid 3b. When the crank pulley main body 3a is superposed, the alignment boss 18a and the boss insertion hole 12b are fitted to each other so that their axes coincide with each other.
[0014]
Since the belt power transmission device 1 of the present invention is configured as described above, a toothed belt is provided between the belt power transmission device 1 and the power transmitted pulley 25 as shown in FIGS. 8 is stretched, the driven part 3 constituted by the crank pulley main body 3a and the lid body 3b is loosely fitted, engaged and supported on the crank disk 2, and the circumferential row drive pin 4 of the crank disk main body 2a and the crank pulley Within the range of mutual clearance in the loose fitting receiving hole 10 of the main body 3a, it moves by gravity, reduces the distance between the shafts with the power-transmitted pulley 25, and stretches in a no-load state in which the toothed belt 8 is slackened. To do.
[0015]
Next, as shown in FIG. 10, when a pedal force is applied to the crank arm 2b to rotate the crankshaft 14, the circumferential row drive pins 4 of the crank disk body 2a rotate the driven portion 3 along the circumferential row. Therefore, as shown in FIG. 10, the driven part 3 is moved by an L width, and the tension of the toothed belt 8 is increased. Therefore, the tooth part 9 of the driven part 3 and the toothed belt 8 can be rotated without causing a jump. The power can be transmitted to the power transmitted pulley 25.
[0016]
【The invention's effect】
From the above, the belt power transmission device of the present invention eliminates the complexity of the structure of this type of device in the past, greatly reduces costs, and is a characteristic inherent to the belt drive device, which is maintenance-free. In addition, a number of characteristics such as quietness and light transmission can be exhibited, and an effect of providing a device having an excellent appearance can be provided.
[Brief description of the drawings]
FIG. 1 is an external left side view showing an embodiment of a belt power transmission device of the present invention.
FIG. 2 is also a plan view.
FIG. 3 is a right side view of the same.
4 is a cross-sectional view taken along line AA in FIG.
5 is a longitudinal sectional view taken along line BB in FIG. 1. FIG.
FIG. 6 is a perspective view of a single crank disk constituting the belt power transmission device.
FIG. 7-a is a perspective view from the inner surface side of the crank pulley main body constituting the belt power transmission device.
FIG. 7-b is a perspective view from the inner surface side of the crank pulley main body constituting the belt power transmission device, showing an embodiment in which a bush is provided in the bearing cylinder portion.
FIG. 8 is also a perspective view from the outer surface side of the lid body constituting the belt power transmission device.
FIG. 9 is a side view for explaining an operating state during no-load driving of the belt power transmission device of the present invention.
FIG. 10 is also a side view for explaining an operating state of the belt power transmission device when driving a load.
FIG. 11 is an exploded perspective view showing a conventional belt power transmission device of this type.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Belt power transmission device 2 Crank disk 2a Crank disk main body 2b Crank arm 3 Driven part 3a Crank pulley main body 3a1 Circumferential substrate part 3b Cover body 4 Circumferential drive pin 4a Base end 5 Collar 6 Elastic ring 7 One outer rim Part 8 toothed belt 9 tooth part 10 loose fitting receiving hole 11 bearing cylinder part 12 body mounting hole 12a nut hole 12b boss fitting hole 13 support cylinder part 14 crankshaft 15 body crankshaft loose fitting hole 16 metal bush 17 other side Outer rim 18 Lid square hole mounting hole 18a Alignment boss 19 Seat 20 Mounting bolt 20a Head 20a1 Square root 21 Nut 22 Washer 23 Lid crankshaft loose fitting hole 24 Raised decoration part 25 Power transmission pulley

Claims (1)

A crank disc 2, that together with the loosely fitted to the crank disc 2, engagement支架is the crank pulley body 3a and met the driven unit 3 which bicycle automatic tensioning mechanism with a belt power transmission device 1 consists of the lid 3b Te, the crank disk 2, the crank disk body 2a, to form a crank arm 2b to fix integrally with a side surface, the crank disc body 2a has a surface opposite to the mounting surface of the crank arm 2b, the crank arm 2b the fixing portion axis and concentric and mutually equally spaced circumferential array drive pin 4 is required the number of collision set in the crank pulley body 3a of the driven part 3, the circumferential substrate portions 3a1 formed on one side surface the class with forming the outer diameter edge on one of the outer sealing rim 7, the tooth portion 9 which meshes a toothed belt 8 on its inner surface, the inner diameter side of the tooth portion 9 A bushing portion 11 which forms a loosely receiving holes 10 of the number corresponding to the circumferential row drive pin 4 of click disc 2, provided raised the support cylinder portion 13 which forms a body mounting hole 12 of the lid 3b A body crankshaft loose fitting hole 15 for loosely fitting the crankshaft 14 at the center of the circumferential substrate portion 3a1 , and the lid 3b of the driven portion 3 is formed on the inner surface of the crank pulley body 3a so as to be closely polymerized , before SL crank pulley body 3a of the body mounting holes 12 and correspondingly on the same circumference Resshi form Naruhai the lid cornered hole mounting holes 18 that match, the outer end of each lid cornered hole mounting hole 18 of its is a seat 19 is formed respectively, a Sumine portion 20a1 formed on the back surface of the head of the mounting bolt 20 fitted through the lid cornered hole mounting hole 18, the tip of the each of the crank pulley body 3a body after inserted into the mounting hole 12, a nut hole 1 which communicates with the body mounting hole 12 and respectively reach a, clamping from both sides of the nut 21 at the portion of the nut bore 12a engaged each screw, and a crank pulley body 3a and the lid body 3b integrally constructed, the lid 3b of the driven part, each The outer surface between the lid body square hole mounting hole 18 is radially formed with a raised decoration portion 24 bulging in an inverted triangular shape from the center lid portion crankshaft loose fitting hole 23 to the outer diameter edge of the lid body 3b . Alignment bosses 18a are formed on the inner surface so as to extend the lid body square hole mounting holes 18 to form bearing holes of the same axis, and the inlets of the mounting holes 12 are formed on the inner surface of the crank pulley body 3a. Further, boss insertion holes 12b having a diameter larger than that of the mounting hole 12 and matching the positioning boss 18a are formed concentrically with the required depth to form the crank pulley main body 3a and the lid 3b . Boss 18a and boss insertion hole 12b that are aligned with each other during polymerization A belt power transmission device with an automatic tension adjusting mechanism for bicycles, which is configured to fit the two axes to coincide with each other.

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