JPH04292291A - Rear disc brake mounting structure - Google Patents

Abstract

PURPOSE:To provide such a rear disc brake mounting structure that is capable of setting a rear brake system intensively to a transmission case separate from a unit swing case, ease of having a rear disc, and simple and rational in change to the drum brake specifications. CONSTITUTION:In a motorcycle mounted with a unit swing type engine, this rear disc brake mounting structure is featured that a transmission case 3 is attached from the wheel side of a unit swing case 1 of this unit swing type engine, thereby forming a transmission chamber 4, and a rear disc braking device 9 is attached to the transmission case 3.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rear disc brake mounting structure for a unit swing type engine.

0002

2. Description of the Related Art In motorcycles equipped with a unit swing type engine, a brake device is generally attached to a unit swing case as shown in Japanese Utility Model Application No. 181490/1983. The brake mounting structure disclosed in the publication is shown in FIG. 1 and will be briefly described. FIG. 1 is a side view of the main parts showing the rear part of the unit swing case 01 and its vicinity. A shock absorber 02 is installed between the end and the vehicle body frame.

[0003] At the rear end of the unit swing case 01, a bracket 03 is fixed with bolts 04, and a braking means 05 using a disc brake is supported on this bracket 03 by a slide pin 06. 07 is a brake disc, and the pads of the braking means 05 sandwich the brake disc 07, which rotates together with the rear wheel, to perform braking.

0004

[Problems to be Solved] As described above, the conventional brake device was attached to the unit swing case 01 via the bracket 03, so a special mounting structure for the brake device was required on the unit swing case, and the rear disc was installed. It was a hassle.

[0005] In recent years, it has been considered to apply the same basic engine to multiple models of motorcycles, and it is desirable that the braking means be applied to the basic engine with either a disc brake specification or a drum brake specification. However, in the case of a unit swing type engine, conventionally the braking means using a disc brake was attached to the unit swing case as described above, but when this was applied to a drum brake specification, the large swing case itself was replaced with a new drum brake. I have to replace it with one for brakes. Especially for small, lightweight, and inexpensive vehicles that use the unit swing type engine, it is extremely unreasonable to prepare a new large item such as a unit swing case.

[0006] The present invention has been made in view of the above points.
The purpose is to provide a rational rear disc brake mounting structure that can be easily converted into a rear disc and can be easily modified to a braking means of a drum brake specification.

[0007]

[Means and operations for solving the problems] In order to achieve the above object, the present invention provides a motorcycle equipped with a unit swing type engine, in which a transmission case is installed from the wheel side of the unit swing case of the unit swing type engine. It is attached to form a transmission chamber, and a rear disc brake device is attached to the transmission case to create a rear disc brake mounting structure.

[0008] It is possible to centrally attach the rear disc brake device to the transmission case, making it easy to use a rear disc brake. Also, if you change the transmission case, which is smaller than the swing case, to one with drum brake specifications, you can easily change the large swing case to one with drum brake specifications.

[0009]

[Embodiment] An embodiment of the present invention illustrated in FIGS. 2 to 10 will be described below. This embodiment is an example in which the present invention is applied to a scooter type motorcycle 100, and FIG. 2 is an overall side view of the scooter type motorcycle 100.

In the scooter type motorcycle 100, a pair of left and right main pipes 102 which are bifurcated from a head pipe 101 and extend downward are bent horizontally to face rearward, and then bent diagonally upward to form a rising portion 103. The left and right pipes are curved at the rear end and connected together to form the vehicle body frame.

A steering stem 104 is fitted into the head pipe 101, and a handle 105 is attached to the upper end of the steering stem 104.
The lower end is connected to a front fork 106, and a front wheel 107 is pivotally supported by the front fork 106.

On the other hand, the rising portion 10 of the main pipe 102
A power unit 10 of a unit swing type engine is swingably disposed below the main pipe 102.
A shock absorber 118 is interposed between the two, and a rear wheel 111 is pivotally supported at the rear end of the power unit 10.

The power unit 10 is covered by a unit swing case 1, and an air cleaner 112 and a carburetor 113 are disposed above the unit swing case 1. Further, a fuel tank 114 is fitted between the left and right horizontal parts of the main pipe 102, and a fuel tank 114 is fitted between the left and right horizontal parts of the main pipe 102.
3, a helmet box 115 is fitted above the power unit 10, and the helmet box 11
A seat 116 is provided above 5 so as to be openable and closable and also serves as a lid.

3 to 7 show a power unit 10 of a unit swing type engine with a disc brake specification, of which FIG. 3 shows the power unit 10.
FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3. FIG.

The power unit 10 includes a front engine unit 11, a central belt transmission mechanism 12, a rear transmission unit 13, and a rear wheel 14, which are integrated by a unit swing case (L side case) 1 and are swingably attached to the vehicle body. is supported by. The unit swing case 1 forms a crankcase portion 1a on the front side, and includes a cylinder 15 projecting slightly diagonally upward toward the front of the engine unit 11, and a piston 1 inside the cylinder 15.
6 and a crankshaft 18 connected via a connecting rod 17.
The crankcase portion 1a partially covers and supports the AC generator 19 and the like disposed on the right end of the crankshaft 18 together with the R-side case 36 (see FIG. 2).

The unit swing case 1 extends rearward from the left side of the crankcase portion 1a to form a swing arm portion 1b, and the swing arm portion 1b is connected to a drive pulley 20 provided at the left end of the crankshaft 18. It forms the right side wall of a driven pulley 21 provided on a rear driven shaft 23 via a clutch 35 and a V-belt 22 spanned between both pulleys 20 and 21, and the left side is covered by a swing case cover 2. A bracket 1d protruding forward below the front end of the swing arm portion 1b is linked 117 to a bracket 103a protruding downward from the rising portion 103 of the main pipe 102.
are connected via.

The rear part of the unit swing case 1 forms a mission case part 1c, and a mission chamber 4 is formed between it and a mission case 3 attached to the right side of the mission case part 1c. The right end of the driven shaft 23 is inserted, and the driven shaft 23
The small diameter gear 24 at the right end of the wheel meshes with the large diameter gear 25 of the intermediate shaft 26, and the small diameter gear 27 of the intermediate shaft 26 and the large diameter gear 28 of the axle 29 mesh with each other to form a speed reduction mechanism.

A hub 30 is fitted onto an axle 29 protruding from the right side of the transmission case 3. The rear wheel 14 is fitted onto the head of a bolt 31 protruding to the right from the hub 30 and tightened with a nut 32, and a brake disc 33 is screwed onto the left side of the hub 30 with a bolt 34.

The mission case 3 attached to the right side of the mission case portion 1c of the unit swing case 1 is concave to the right side to form a mission chamber 4, as shown in FIGS. 4 and 5, and has a driven shaft 23 on the inner surface. , intermediate shaft 26
Supporting recesses 3a and 3b and a circular hole 3c for penetrating and supporting the axle 29 are formed, and female threads 3d are provided at several locations on the periphery.

The mission case portion 1c of the unit swing case 1 corresponds to the female thread 3d of the mission case 3.
A circular hole is bored in the unit swing case 1, and the mission case 3 is applied to the mission case part 1c of the unit swing case 1 from the right side, and the bolt 5 is passed through the circular hole from the left side and screwed into the female thread 3d. The mission case 3 can be easily fixed.

Two parts of the peripheral edge of the mission case 3 protrude outward from the mission case part 1c of the unit swing case 1, and circular holes are formed in the upwardly protruding protruding part 3e and the rearward protruding protruding part 3f, respectively. 3g and 3h are drilled. Both protrusions 3e, 3f
A bracket 6 is applied from the right side in between to construct the structure.

As shown in FIGS. 6 and 7, the bracket 6 has female threads 6b corresponding to the circular holes 3g and 3h of the protrusions 3e and 3f of the transmission case 3 at both front and rear ends of a connecting portion 6a bent at the center. 6c is formed, and the front end female thread 6b
A circular hole 6e, which is elongated from the left side surface, is formed in a bulging portion 6d that bulges upward and to the right from the rear end female thread 6c, and a protruding portion 6f that protrudes upward slightly forward of the rear end female thread 6c.
A rectangular space 6h is formed between the protruding portion 6d and the protruding portion 6f, and a circular hole 6g is bored in the protruding portion 6f.

[0023] The bracket 6 is attached to the mission case 3.
The bracket 6 is attached to the transmission case 3 by fitting and screwing the bolt 40 into contact with the rear upper part of the transmission case 3 from the right side, aligning the internal threads 6b and 6c with the circular holes 3g and 3h.

[0024] Circular hole 6 in the bulge 6d on the front side of the bracket 6
e and the slide pin 7 in the circular hole 6g of the rear protrusion 6f.
, 8 are fitted and inserted, and the caliper 9 is supported so as to be slidable left and right via the slide pins 7 and 8. The caliper 9 is disposed in a rectangular space 6h above the connecting portion 6a of the bracket 6, spanning over the brake disc 33, and is a slide whose base end is fixed to a circular hole 9b at the tip of a forward projecting piece 9a. A pin 7 is provided to protrude rightward, and the slide pin 7 is slidably inserted into a circular hole 6e on the front side of the bracket 6 to be supported on the front side, and a protrusion 9c protrudes downward on the rear side.
The rear circular hole 6 of the bracket 6 is inserted into the circular hole 9d bored in the circular hole 9d.
A slide pin 8 whose base end is fixed to g and protrudes to the left is inserted and supported.

Therefore, the caliper 9 is supported by the front and rear slide pins 7 and 8 so as to be slidable left and right with respect to the bracket 6. A boot 7a is placed on the front slide pin 7 between the bracket 6 and the caliper 9, and a boot 8a is placed on the rear slide pin 8 at a portion exposed to the left side from the circular hole 9d of the protrusion 9c of the caliper 9. is covered. The caliper 9, which is disposed astride both sides of the brake disc 33, has pads 9e and 9f on both the left and right sides of the brake disc 33, and a piston 9g.
With this operation, the pads 9e and 9f sandwich the brake disc 33 and perform braking.

As described above, in the power unit 10 with disc brake specifications, the transmission case 3 is attached to the unit swing case 1, and the caliper 9 is attached to the mission case 3 via the bracket 6. In this way, by centrally attaching the rear brake system functions to the transmission case 3, which is separate from the unit swing case 1, and by attaching the caliper 9 of the rear disc brake to the transmission case 3, it has become extremely easy to use a rear disc brake.

Furthermore, if a drum brake is to be attached to the unit swing type engine of this power unit 10 to make it a drum brake specification, it is sufficient to leave the unit swing case 1 as is and change the transmission case to one for the drum brake. .

FIG. 8 is a side view of the power unit 50 in a drum brake specification, and FIG. 9 is a sectional view taken along the line IX--IX in FIG. The only difference from the power unit 10 is a transmission case 51 and a brake mechanism.

The mission case 51 is formed to correspond to the right side of the mission case portion 1c of the unit swing case 1, and is therefore connected to the mission case 3.
They have approximately the same shape, and also have internal threads 51a formed corresponding to a plurality of circular mounting holes provided in the mission case portion 1c of the unit swing case 1, and are screwed in with bolts 52 from the left side. The mission case 51 allows the mission case portion 1 of the unit swing case 1 to
A mission chamber is formed between C and C, and the mission mechanism inside is the same.

However, the circular hole 51c is located diagonally rearward of the circular hole 51b that penetrates and supports the axle 29 of the mission case 51.
is provided in a protruding manner, and the brake cam 53 is rotatably fitted into the circular hole 51c. Further, as shown in FIG. 9, an anchor pin 54 is fitted in the transmission case 51 at a position symmetrical to the brake cam 53 with respect to the axle 29.

A wheel hub/brake drum 55 is fitted onto the axle 29 protruding outward from the transmission case 51, and covers the outer periphery of the brake shoe pivotally supported by the anchor pin 54. A cam 53a is formed at the right end of the brake cam 53 and abuts on the end of the brake shoe, a brake cam lever 56 is fitted at its base end at the left end, and a brake rod 57 is mounted at the tip of the brake cam lever 56. It is fixed. The rear wheel 59 is tightened to the hub 55 by fitting the circular holes of the rear wheel 59 into a plurality of bolts 58 protruding from the outer periphery of the hub/brake drum 55 and screwing them with nuts 60.

[0032] Power unit 50 with drum brake specifications
has the above structure, and by operating the brake cam 53 supported by the transmission case 51, the cam 53a
opens the brake shoes outward, brings the brake lining into contact with the brake drum 55, and applies braking by friction.

As described above, the disc brake mounting structure according to this embodiment can be changed to a drum brake specification by simply changing the small transmission case 3, and the brake specification can be easily changed in the same unit swing type engine. This makes it possible to realize a rational engine configuration.

In the case of the disc brake specification, the caliper body slides, but it is also possible to fix the caliper body and attach it directly to the transmission case without using a bracket. The caliper in this case is of the opposed piston type, and the installation of such a caliper is illustrated in FIGS. 11 to 13.

The mission case 71 has almost the same shape as the mission case 3 for the disc brake specification, and is fixed from the right side to the mission case portion 1c of the unit swing 1. The position of one of the protrusions 71a and 71b protruding outward from the mission case portion 1c of the swing 1 is slightly different from that of the mission case 3, and has been moved to the rear.

[0036] Each protrusion 71a, 71b has a circular hole 71c,
71d is drilled, and bolts 7 are inserted into the same circular holes 71c and 71d.
2 pass through each to directly fixedly support the caliper 73.

That is, the caliper 73 has circular holes 71c,
71d, and two bolts 72 pass through the circular holes 71c and 71d from the left side, respectively, and are screwed into the female threaded portion 73a to be directly tightened to the transmission case 71. In this way, the caliper 73 installed between the front and rear protrusions 71a and 71b of the mission case 71,
It is arranged so as to straddle above the brake disc 74.

A hub 76 is fitted onto an axle 75 protruding to the right from the transmission case 71, and a rear wheel 78 is fitted onto a bolt 77 protruding from the hub 76 to the right and tightened with a nut 79.

A brake disc 74 is screwed onto the left side of the hub 76 with bolts 80 so as to rotate together.

The caliper 73 that straddles the brake disc 74 has pistons 81 and 82 on both sides of the brake disc 74 facing each other with the brake disc 74 in between.
Friction pads 85 and 86 having back plates 83 and 84 in contact with the head portions of both pistons 81 and 82 are disposed on both sides of the brake disc 74. Friction pad 8
The back plates 83 and 84 of 5 and 86 are slidably suspended from hanger pins 87 installed between both sides of the caliper 73.

Therefore, when pressure oil is supplied to the left and right cylinders of the caliper 73, the left and right pistons 81 and 82 approach each other and press the friction pads 85 and 86, so that the friction pads 85 and 86 sandwich the brake disc 74 and perform braking. can be applied.

Even a caliper of the opposed piston type in which the caliper body is fixed in this way can be used by being directly attached to the transmission case 71, which has a slightly different shape, thereby reducing the number of assembly steps and cost.

As shown in FIGS. 11 and 13, the unit swing case 1 includes a mission case section 1.
The lower end of a shock absorber 118 is attached to the upper part of the air cleaner 112 with a bolt 119, and a bracket 112a protruding downward from the rear of the bottom wall of the air cleaner 112 located on the left side of the shock absorber 118 is attached to the mission case portion 1c of the unit swing 1. A bolt 120 is screwed into and supported by a bulging portion 1d that bulges out from the left side surface of the holder. The bracket 112a extends slightly further downward from the screwed part to the unit swing case 1, and the extending part 112a
A brake hose 88 extends from the caliper 73 and forms a gap between the unit swing case 1 and the brake hose 88.
passes through this gap and moves forward along the upper side of the unit swing case 1, being partially stopped by a holder 89.

Next, a description will be given of a case in which the caliper is directly attached to the transmission case without using a bracket, and the caliper body slides, similar to the above example. FIGS. 14 and 15 show an example thereof.

The mission case 90 has protrusions 90a and 90b adjacent to each other on its outer periphery.
The base end is fixed to the caliper 90b, and slide pins 91 and 92 protrude to the right side, and the slide pins 91 and 92 are slidably inserted into the circular holes of the slide portion 93a of the caliper 93 and supported. That's what I do. In this way, the caliper mounting part is structured to also serve as the sliding part of the caliper, so that the caliper 93 can be directly supported by the transmission case 90, and costs can be reduced.

[0046]

[Effects of the Invention] By attaching the rear disc brake device to the transmission case that is separate from the unit swing case, the rear disc brake can be installed centrally to the transmission case, making it easy to use a rear disc brake. . In addition, by changing the small transmission case, you can easily change to a drum brake specification, making it possible to realize a rational and ideal engine configuration.

[Brief explanation of drawings]

FIG. 1 is a side view of main parts showing a conventional brake mounting structure.

FIG. 2 is an overall side view of a scooter type motorcycle according to an embodiment of the present invention.

FIG. 3 is a side view of the power unit of the same embodiment.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 is a side view showing the attachment structure of the transmission case and the caliper.

FIG. 6 is a side view of the bracket.

FIG. 7 is a sectional view taken along the line VII-VII in FIG. 5;

FIG. 8 is a side view of a power unit with drum brake specifications.

9 is a sectional view taken along the line IX-IX in FIG. 8. FIG.

FIG. 10 is a sectional view taken along the line XX in FIG. 8;

FIG. 11 is a side view of another power unit with disc brake specifications.

12 is a sectional view taken along the line XII-XII in FIG. 11. FIG.

FIG. 13 is a rear view of the same essential parts.

FIG. 14 is a side view of a rear disc brake device according to another embodiment.

15 is a sectional view taken along the line XV-XV in FIG. 13. FIG.

[Explanation of symbols]

1... Unit swing case, 2... Swing case cover, 3... Mission case, 4... Mission chamber, 5... Bolt, 6... Bracket, 7, 8... Slide pin, 9... Caliper, 10... Power unit, 11... Engine unit, 12... Belt transmission mechanism, 13... Mission unit, 14... Rear wheel, 15... Cylinder, 16... Piston, 17... Connecting rod, 18... Crankshaft, 19... A
C generator, 20... Drive pulley, 21... Driven pulley, 22... V belt, 23... Driven shaft, 24,
25... Gear, 26... Intermediate shaft, 27, 28... Gear, 29...
Axle, 30...Hub, 31...Bolt, 32...Nut, 33
...brake disc, 34...bolt, 35...clutch,
36...R side case, 40...Bolt, 50...Power unit, 51...Mission case, 52...Bolt, 53...Brake cam, 54...Anchor pin, 55...Hub and brake drum, 56...Brake cam lever, 57...Brake rod, 58...Bolt, 59...Rear wheel, 60...Nut, 71...Mission case, 72...Bolt, 73...
Caliper, 74...brake disc, 75...axle, 7
6...Hub, 77...Bolt, 78...Rear wheel, 79...
Nut, 80... Bolt, 81, 82... Piston, 83,
84... Back plate, 85, 86... Friction pad, 87... Hanger pin, 88... Brake hose, 89... Holder, 90...
Mission case, 91, 92...Slide pin, 93...
caliper. 100...Scooter type motorcycle, 101
...Head pipe, 102 ...Main pipe, 103
... Rising part, 104 ... Steering stem, 105
...Handle, 106 ...Front fork, 107...
Front wheel, 111 ... Rear wheel, 112 ... Air cleaner, 11
3...Carburetor, 114...Fuel tank, 115
...Helmet box, 116 ...Seat, 117...
Link, 118...Buffer, 119, 120...Volt.

Claims (1)

[Claims] Claim 1: In a motorcycle equipped with a unit swing type engine, a mission case is attached from the wheel side of the unit swing case of the unit swing type engine to form a mission chamber, and a rear disc brake device is attached to the mission case. The rear disc brake mounting structure is characterized by: