Title of Invention	"A PARKING BRAKE"
Abstract	A parking brake of a drum brake type which is mounted on a wheel separately from a traveling brake, wherein in a recessed portion formed in a wheel body of the wheel, a brake drum which is provided as a member separate from the wheel body is arranged.

Full Text

The present invention relates to a parking brake. The present invention relates to a drum-brake-type parking brake structure which is used in a motorcycle or the like. [0002] [Prior Art] Conventionally, in a motorcycle or the like, for example, besides a traveling brake which is constituted of a hydraulic disc brake, a mechanical parking brake may be provided. With respect to such a parking brake, there has been known a parking brake which is constituted as a drum brake which integrally mounts a brake drum on a hub portion of a wheel body of a wheel and mounts a brake shoe in the inside of the brake drum (see, for example, patent literature 1). On the other hand, a mounting portion for mounting a brake disc of the traveling brake and the like are also integrally mounted on the hub portion of the wheel body and a portion which is surrounded by the mounting portion is utilized as the brake drum. [0003] [patent literature 1] Japanese Unexamined Patent Publication Heill(1999)-310184 [0004] [Problems to be solved by the Invention] However, in the above-mentioned conventional parking brake, when the traveling brake becomes large-sized to enhance the traveling performance of a vehicle, the parking brake which is not influenced by the traveling performance is also large-sized. The present invention has been made in view of such circumstances and it is an object of the present invention to provide the parking brake structure which can reduce a weight and a cost thereof by enhancing the degree of freedom in setting a brake size. [0005] [Means for Solving the Problem] As means for solving the above-mentioned problems, the invention described in claim 1 is directed to a parking brake structure of a drum brake type which is mounted on a wheel (for example, a rear wheel 4 in the embodiment) separately from a traveling brake (for example, a rear brake 6 in the embodiment), wherein in a recessed portion (for example, a recessed portion 55 in the embodiment) formed in a wheel body (for example, a wheel body 32 in the embodiment)of the wheel, a brake drum (for example, a brake drum 51 in the embodiment) which is provided as a member separate from the wheel body is arranged. [0006] According to this constitution, a shape of the wheel body of the wheel and a shape of the brake drum do not interfere with each other and hence, the degree of freedom in setting a brake size of the parking brake can be enhanced and, at the same time, the degree of freedom of the shape of the wheel body can be enhanced. Further, by constituting the wheel body and the brake drum as separate members from each other, it is possible to have the compatibility between the wheel body and the brake drum and hence, the generality is enhanced and the degree of freedom in selecting materials can be also enhanced. Further, it is unnecessary to form the wheel body together with the brake drum by casting, the wheel body and the brake drum can be manufactured easily. [0007] The invention described in claim 2 is characterized in that the brake drum is replaceably mounted on the wheel body and is supported on an axle (for example, a rear axle 30 in the embodiment) of the wheel body. [0008] Due to such a constitution, while the wheel body and the brake drum can be individually assembled to the axle, the wheel body and the brake drum can be removed from the axle individually. [0009] The invention described in claim 3 is directed to a parking brake structure of a drum brake type which is mounted on a wheel (for example, a rear wheel 104 in the embodiment) separately from a traveling brake (for example, a rear brake 6 in the embodiment), wherein a brake drum (for example, a brake drum 151 in the embodiment) which constitutes a member separate from a wheel body (for example, a wheel body 132 in the embodiment) of the wheel is provided, and the brake drum is replaceably mounted on the wheel body and is supported on an axle (for example, a rear axle 30 in the embodiment) of the wheel. [0010] According to this constitution, a shape of the wheel body of the wheel and a shape of the brake drum do not interfere with each other and hence, the degree of freedom in setting a brake size of the parking brake can be enhanced and, at the same time, the degree of freedom of the shape of the wheel body can be enhanced. Further, by constituting the wheel body and the brake drum as separate members from each other, it is possible to have the compatibility between the wheel body and the brake drum and hence, the generality is enhanced and the degree of freedom in selecting materials can be also enhanced. Further, it is unnecessary to form the wheel body together with the brake drum by casting, the wheel body and the brake drum can be manufactured easily. Further, while the wheel body and the brake drum can be individually assembled to the axle, it is possible to remove the wheel body and the brake drum from the axle individually. [0011] The invention described in claim 4 is characterized" in that the brake drum is engaged with the axle in serration fitting together with wheel body. [0012] Due to such a constitution, compared to a case in which the wheel body and the brake drum are connected to each other using bolts and nuts, for example, it is possible to connect the brake drum and the axle in a non-rotatable manner with the simple constitution and in a compact form. [0013] [Mode for Carrying Out the Invention] The mode for carrying out the present invention is explained in conjunction with drawings hereinafter. The present invention relates to a parking brake of a drum brake type which is mounted on a wheel separately from a traveling brake, wherein in a recessed portion formed in a wheel body of the wheel, a brake drum which is provided as a member separate from the wheel body is arranged. [Brief Description of the Drawings] [Fig. 1] A side view of a motorcycle according to an embodiment of the present invention. [Fig. 2] A cross-sectional view taken along a line A-A in Fig. 1. [Fig. 3] An enlarged constitutional view of an essential part shown in Fig. 2. [Fig. 4] A side view showing the essential part shown in Fig. 2 from the left side. [Fig. 5] A side view showing the essential part shown in Fig. 2 from the right side. [Fig. 6] An enlarged constitutional view corresponding to Fig. 3 in the second embodiment of the present invention. A motorcycle 1 shown in Fig. 1 is a scooter type vehicle having a low-floor 2, wherein a front brake 5 and a rear brake 6 which are respectively constituted of hydraulic disc brakes are provided to a front wheel 3 and a rear wheel 4 as traveling brakes respectively. The front wheel 3 is pivotally supported on a front fork 7 and the front fork 7 is steerably and pivotally supported on a head pipe 11 of a vehicle body frame 10 by way of a handle stem 8. A handle 12 is mounted on an upper end portion of the handle stem 8 and brake levers 13, 13 which are manipulation elements of the rear brake 6 and the front brake 5 are respectively arranged at left and right grip portions of the handle 12. [0014] The vehicle body frame 10 is constituted as a so-called cradle type which includes a main pipe 14 extending substantially rearwardly from the head pipe 11 and a down pipe 15 extending substantially downwardly from the head pipe 11 and, thereafter, being curved and connected to the approximately center in the longitudinal direction of the main pipe 14. The vehicle body frame 10 is covered with a body cover 16 and supports these parts. The body cover 16 includes an inner-side cover 16a, a front cowl 16b and an undercover portion 16c which is disposed behind the front cowl 16b and extends rearwardly contiguously with the front cowl 16b rearwardly and downwardly, wherein a portion of the body cover 16 forms the low floor 2. At a side above and behind the body cover 16, an article storage chamber (not shown in the drawing) in the body cover 16 and an occupant seat 17 which constitutes a lid portion of the article storage chamber and can be opened or closed are arranged. [0015] A front portion of a swing unit 20 is tiltably and pivotally supported on a rear portion of the vehicle body frame 10 by way of a link mechanism 18. The swing unit 20 is formed as an integral body constituted of an engine 21 which is provided at a front portion thereof and a power transmission mechanism 22 provided at a rear portion thereof and the rear wheel 4 is connected to an output shaft provided at the rear portion of the swing unit 20. Here, numeral 22A indicates a power transmission casing which houses the power transmission mechanism 22. A pair of left and right rear cushions 23, 23 are arranged between a rear end portion of the swing unit 20 and a rear end portion of the vehicle body frame 10. Here, numeral 24 indicates a fuel tank, numeral 25 indicates a radiator, numeral 26 indicates an air cleaner casing and numeral 27 indicates a silencer. [0016] As shown in Fig. 2, the left side of the rear portion of the crankcase 21A of the engine 21 is extended rearwardly and the transmission casing 22A which houses the power transmission mechanism 22 is formed of this extending portion and a transmission cover 22B. A gear cover 28 is mounted on a right side of the rear portion of the transmission casing 22A and a rear axle 30 which constitutes an output shaft of the power transmission mechanism 22 is rotatably supported on the gear cover 28 byway of casing-side radial ball bearings (hereinafter referred to as case-side bearings) 31. Further, the rear wheel 4 is arranged at the right side of the rear portion of the transmission casing 22A and behind the engine 21, wherein by connecting the rear wheel 4 and the rear axle 3 0 in a non- rotatable manner, a driving force of the engine 21 is transmitted to the rear wheel 4 by way of the power transmission mechanism 22. [0017] A wheel body 32 of the rear wheel 4 is, for example, an aluminum diecast product which is formed of an integral body constituted of a rim portion 34 on which a tire 33 is mounted, a hub portion 35 through which the rear axle 30 penetrates, and a disc portion 36 which extends between the rim portion 34 and the hub portion 35. In this embodiment, the disc portion 36 is provided at a position which is disposed rightwardly from the center in the left-and-right direction of the rear wheel 4 (the center in the vehicle width direction of the motorcycle 1) and is formed in a bulged manner to form a rightwardly convex arcuate shape. [0018] Further, the hub portion 35 which is positioned at the center of the disc portion 3 6 includes a hub body 37 which has an inner peripheral portion formed in a substantially cylindrical shape in which an iron-made wheel color 37A is inserted by casting, a base portion 38 which spreads smoothly at a right side of the hub body 37 and is formed contiguously with the disc portion 36, a plurality of left-side boss portions 41 which are formed in a leftwardly projecting manner from the base portion 38 and on which a pulser disc 4 0 of a vehicle speed detection device 39 is mounted, and a plurality of right-side boss portions 43 which are rightwardly projected from the base portion 38 and on which a brake disc 42 of the rear brake 6 is mounted. To respective right-side boss portions 43, inner-peripheral-side portions of the annular brake disc 42 are fixed using fixing bolts 44. In the same manner, inner peripheral side portions of the annular pulser disc 40 are fixed to the respective left-side boss portions 41 using fixing small bolts 45. [0019] A right end portion of the rear axle 3 0 which projects rightwardly through the hub portion 35 is rotatably supported on an auxiliary arm 46 by way of an arm-side radial ball bearing (hereinafter referred to as an arm-side bearing) 47. The auxiliary arm 46 has a front end portion thereof mounted on a rear portion of the right side of the crankcase 21A and is arranged at a right side of the rear wheel 4 while being gently bent in a crank shape such that a rear portion thereof is displaced rightwardly. Here, the silencer 27 is arranged at the right side of the auxiliary arm 46. A rear portion of the auxiliary arm 46 is arranged in a spaced apart manner from the hub portion 35 by a given distance, and the brake disc 42 which is supported on the right-side boss portion 43 is arranged at an approximately intermediate position between the auxiliary arm 4 6 and the hub portion 35. [0020] To explain the constitution along with Fig. 4, the auxiliary arm 46 has a wide-width shape in the vertical direction and is formed to narrow a width thereof in the vertical direction in the rearward direction. Further, the auxiliary arm 46 has two upper and left portions at a front end portion thereof fastened to the crank case 21A using bolts. Here, to rear end portions of the auxiliary arm 46 and the transmission casing 22, connecting portions 23A, 23A for mounting lower end portions of the respective rear cushions 23, 23 are respectively provided. In an approximately center portion of the auxiliary arm 46 as viewed in a side view, an opening 46a is formed, and a brake caliper 48 of the rear brake 6 is arranged to face the opening 46a. A caliper bracket 48a is fixed to the auxiliary arm 46 and the brake caliper 48 is mounted on the auxiliary arm 46 by way of the caliper bracket 48a. [0021] A pulser sensor 49 of the vehicle speed detection device 39 is arranged behind the gear cover 28 and a wheel speed can be detected by making the pulser sensor 49 detect an interval between a plurality of slits formed in the pulser disk 40. Further, between the auxiliary arm 46 and the hub portion 35, a drum brake 50 which functions as a parking brake of the motorcycle 1 is provided. [0022] As shown in Fig. 3, the drum brake 50 includes a brake drum 51 which is mounted on the rear axle 30 in a non-rotatable manner, and a pair of brake shoes 52, 52 which are supported on the auxiliary arm 46 such that the brake shoes 52, 52 can be brought into friction contact with an inner periphery of the brake drum 51. The brake drum 51 is formed of an integrally connected body constituted of an iron-made drum body 53 having an approximately bottomed cylindrical shape which opens at a right side (an outside in the vehicle width direction) and a drum hub 54 also made of iron and having a cylindrical shape which is allowed to be inserted into an insertion hole formed in the center of a bottom portion of the drum body 53. The insertion hole forms a cylindrical wall 53a which projects rightwardly from the bottom portion of the drum body 53 at a peripheral portion thereof, and the drum body 53 and the drum hub 54 are connected in a state that an inner peripheral surface of the cylindrical wall 53a and an outer peripheral surface of the drum hub 54 are brought into contact with each other. [0023] Here, the respective right-side boss portions 43 are formed to be contiguous with each other in the circumferential direction of the hub portion 35 and hence, a substantially circular recessed portion 55 which has a right side (an outside in the vehicle width direction) thereof opened is formed at the right side of the hub portion 35. The drum body 53 is formed to be substantially aligned with the recessed portion 55 and the brake drum 51 is housed in the inside of the recessed portion 55 with a gap in a state that the drum body 53 is mounted on the rear axle 30. [0024] With respect to the auxiliary arm 46, a working hole 57 which is concentric with the rear axle 30 is formed in an arm body 56 thereof. Here, the working hole 57 is an escape hole for a fixing nut 58 described later which is provided for fixing the wheel body 32, the brake drum 51 and the like to the rear axle 30. That is, the working hole 57 is a hole for inserting a fastening tool. Further, at a left side of the auxiliary arm 46, an arm-side boss portion 59 which projects toward the hub portion 35 side from the arm body 56 and holds the arm-side bearing 47 with an inner peripheral portion thereof is provided. [0025] To explain the constitution also in conjunction with Fig. 5, on the radially outside of the arm-side boss portion 59, a base portion 60 which supports respective brake shoes 52 of the drum brake 50 is integrally formed. That is, the base portion 60 is integrally formed with the auxiliary arm 46. An anchor pin 61 which constitutes a support shaft for the respective brake shoes 52 is mounted on the base portion 60 in an erected manner, while a cam shaft 62 which operably expands the respective brake shoes 52 to bring the respective brake shoes 52 into friction contact with the inner periphery of the brake drum 51 is rotatably supported on the base portion 60. Further, the respective brake shoes 52 which are supported on the base portion 60 are arranged to face the inside of the brake drum 51. [0026] The cam shaft 62 penetrates the base portion 60 in the rightward direction and an operation lever 63 is mounted on a penetrating portion of the cam shaft 62 in a non-rotatable manner. The operation lever 63 is interlocked with a manipulating element such as a parking lever or the like (omitted from the drawing) by way of a cable 63a. Then, when the manipulating element is manipulated, the cam shaft 62 is driven by the operation lever 63 and hence, the respective brake shoes 52 are expanded and are brought into friction contact with the inner periphery of the brake drum 51. When the manipulating element is locked in this state, the rotation of the rear wheel 4 is held in a braked state thus functioning as a parking brake. [0027] To a right-side peripheral portion of an outer wall of the drum body 53, an extension portion 64 which extends rightwardly than the opening formed in the recessed portion 55 of the hub portion 35 and also widens a diameter thereof by way of a stepped portion is provided. On the other hand, to the base portion 60, a fold-back portion 65 which is formed to sandwich the extension portion 64 in the radial direction is provided. With the provision of these extension portion 64 and fold-back portion 65, the so-called labyrinth structure is formed whereby mud, sand or the like at the time of traveling in the rain and pad worn-out powders or the like of the rear brake 6 hardly enter the inside of the brake drum 51. [0028] At a portion of the gear cover 28 through which the rear axle 30 is inserted, a cover hub portion 66 is formed and a case-side bearing 31 is held by an inner peripheral portion of the cover hub portion 66. An annular stepped portion 67 which is brought into contact with an inner lace of the case-side bearing 31 from the left side is formed on the rear axle 30. Here, an inner peripheral projection 68 which is brought into contact with an outer lace of the case-side bearing 31 from the right side is formed on the cover hub portion 66. With the right side of the inner lace of the case-side bearing 31, the left end of the hub body 37 of the hub portion 35 is brought into contact by way of a collar 69. Further, with the right end of the hub body 37, the left end of the drum hub 54 of the brake drum 51 is brought into contact. [0029] Here, between an outer peripheral portion of the rear axle 30 and an inner peripheral portion of the hub body 3 7 and an inner peripheral portion of the drum hub 54, serrations which respectively correspond to these portions are formed. Due to such a constitution, the rear axle 30 and the hub body 37 (hub portion 35) as well as the rear axle 30 and the drum hub 54 (brake drum 51) are connected to each other in a non-rotatable manner by serration fitting. That is, the brake drum 51 which is replaceably mounted on the wheel body 32 is supported on the rear axle 30. [0030] The arm-side bearing 47 has a diameter smaller than a diameter of the case-side bearing 31 and, corresponding to such a relationship, the rear axle 30 has the diameter thereof narrowed at the left side of the arm-side bearing 47. That is, a narrow-diameter portion 70 is formed on a portion of the rear axle 30 at a position close to the right distal end of rear axle 30. Male threads are formed in a distal end portion of the narrow diameter portion 70 and the fixing nut 58 is threaded into the male threads. [0031] A right end of the drum hub 54 is brought into contact with the left side of an inner lace of the arm-side bearing 47 and a right side of the inner lace of the arm-side bearing 47 is brought into contact with the fixing nut 58 by way of the collar 71. That is, between the annular stepped portion 67 of the rear axle 3 0 and the fixing nut 58, the inner lace of the case-side bearing 31, the collar 69, the hub portion 35, the brake drum 51, the inner lace of the arm-side bearing 47 and the collar 71 are arranged in parallel in the axial direction and these components are fixed to the rear axle 30 by fastening the fixing nut 58. Here, the auxiliary arm 46 is provided with a fixing retainer ring 72 and an inner peripheral projecting portion 73 which are brought into contact with the outer lace of the arm-side bearing 47 from left and right sides so as to restrict the movement of the arm-side bearing 74 in the axial direction. [0032] As described above, the parking brake structure of the above-mentioned embodiment is of a drum brake type which is provided separately from the rear brake 6 which constitutes the traveling brake on the rear wheel 4 of the motorcycle 1 and the brake drum 51 which constitutes a member separate from the wheel body 32 is arranged in the inside of the recessed portion 55 formed in the wheel body 32 of the rear wheel 4. Accordingly, a wheel shape of the rear wheel 4, particularly a shape of the hub portion 35 and a shape of the brake drum 51 are not influenced from each other. To be more specific, when the rear brake 6 is large-sized to enhance the traveling performance of the motorcycle 1, although the diameter of the hub portion 35 of the wheel body 32 of the rear wheel 4 is increased along with the large-sizing of the rear brake 6, the brake drum 51 is not large-sized. Further, no limitation is imparted to a shape of the wheel body 32 including the increase of wall thickness of the hub portion 35 for suppressing the brake drum 51 to a proper size. [0033] Accordingly, the degree of freedom in designing a brake size (a brake capacity) of the drum brake 50 which constitutes the parking brake is enhanced, and at the same time, the degree of freedom in the shape of the wheel body 32 is also increased whereby the weight and the cost can be reduced based on the optimum design. Further, by constituting the wheel body 32 and the brake drum 51 as separate members from each other, it is possible to have the compatibility between the wheel body 32 and the brake drum 51 and hence, the generality is enhanced and the degree of freedom in selecting materials can be also enhanced. Further, it is unnecessary to form the wheel body 32 together with the brake drum 51 by casting, the wheel body 32 and the brake drum 51 can be manufactured easily. [0034] Further, in the above-mentioned parking brake structure, the brake drum 51 is replaceably mounted on the wheel body 32 and is supported on the rear axle 3 0 and hence, while the wheel body 32 and the brake drum 51 can be individually assembled to the rear axle 30, the wheel body 32 and the brake drum 51 can be removed from the rear axle 3 0 individually. Accordingly, assembling and maintenance around the rear wheel 4 can be facilitated. [0035] Further, in the above-mentioned parking brake structure, the brake drum 51 is engaged with the rear axle 30 in serration fitting together with the wheel body 32. Accordingly, compared to a case in which the brake drum 51 is connected to the wheel body 32 using bolts and nuts or the like, for example, it is possible to non-rot atably connect the brake drum 51 and the rear axle 30 with the simple constitution and in a compact form. Accordingly, it is possible to reduce the number of parts and the assembling man-hours and can suppress the weight and the cost while maintaining the reliable brake performance. [0036] The second embodiment of the present invention is explained in conjunction with Fig. 6. This embodiment differs from the above-mentioned first embodiment with respect to a point that the right-side boss portion 43 and the recessed portion 55 are eliminated from the hub portion of the wheel body and the brake disc of the rear brake is fixed to the brake drum which constitutes a member different from the wheel body. Here, parts corresponding to the parts of the first embodiment are given same symbols and the explanation thereof is omitted. [0037] As shown in Fig. 6, a hub portion 135 of a wheel body 132 of a rear wheel 104 of a motorcycle 101 includes a hub body 37 which is formed such that the hub body 37 projects leftwardly from a disc portion 36 and in which an iron-made wheel collar 37A is formed by casting, a base portion 38 which smoothly spreads at the right side of the hub body 37 and is formed contiguously with the disc portion 36, and a plurality of left-side boss portions 41 which are formed in a leftwardly projecting manner from boss portions 41 from the base portion 38 and on which a pulser disc 40 of a vehicle speed detection device 39 is mounted. An inner-peripheral-side portion of an annular pulser disc 40 is fixed to respective left-side boss portions 41 by small fixing bolts 45. [0038] In the vicinity of the center between an auxiliary arm 46 and the hub portion 135, a brake disc 42 is provided and a brake caliper 48 which corresponds to the brake disc 42 is arranged to face an opening 46a of an auxiliary arm 46 (see Fig. 4). Further, between the auxiliary arm 46 and the hub portion 135, a drum brake 150 which constitutes a parking brake is provided. [0039] The drum brake 150 includes a brake drum 151 which is mounted on a rear axle 30 in a non-rotatable manner, and a pair of brake shoes 52, 52 which are supported on the auxiliary arm 46 to allow the brake shoes 52, 52 come into friction contact with an inner periphery of the brake drum 151. The brake drum 151 is an aluminum diecast product in the same manner as the wheel body 132, for example. The brake drum 151 is formed of an integral body constituted of a body portion 153 which is formed in an approximately bottomed cylindrical shape having a right side thereof (an outside in the vehicle width direction) opened and has an iron-made drum body 153A formed on an inner peripheral wall by casting and a drum hub portion 154 which is formed in a projecting manner from the center of a bottom portion of the body portion 153 and has an iron-made drum collar 154A formed by casting. [0040] A peripheral wall 143 of the brake drum 151 has a large wall thickness in the radial direction and a plurality of nut holes which correspond to the brake disc 42 and are arranged in parallel with the axial direction are formed in the peripheral wall 143 . Due to such a constitution, the peripheral wall 143 of the brake drum 151 constitutes a mounting portion of the brake disc 42 and by fastening fixing bolts 44 into respective nut holes in a state that the brake disc 42 is brought into contact with a right end of the peripheral wall 143, the brake drum 151 and the brake disc 42 are integrally connected with each other. [0041] At the left side of the auxiliary arm 46, an arm-side boss portion 59 which projects in the direction toward the hub portion 135 from the arm body 56 and holds an arm-side bearing 47 by an inner peripheral portion thereof is provided, while in the vicinity of the arm-side boss portion 59, an annular base portion 160 which supports the respective brake shoes 52 of the drum brake 150 is arranged. A base portion 160 and the auxiliary arm 46 are constituted as separate members and the base portion 160 is supported on the auxiliary arm 46 in a non-rotatable manner. On the base portion 160, an anchor pin 61 which constitutes a support shaft for respective brake shoes 52 and a cam shaft 62 which is operable to expand the respective brake shoes 52 are respectively arranged. Further, the respective brake shoes 52 which are supported by the base portion 160 are arranged to face the inside of the brake drum 151. Here, on an outer peripheral portion of the base portion 160, flange portions 165A, 165B which make water drops or foreign substances difficult to enter the inside of the brake drum 151 are formed. [0042] Between an outer peripheral portion of the rear axle 30 and an inner peripheral portion of the hub body 37 and an inner peripheral portion of the drum hub portion 154 , serrations which respectively correspond to these portions are formed. Due to such a constitution, the rear axle 3 0 and the hub body 37 (hub portion 13 5) as well as the rear axle 30 and the drum hub portion 154 (brake drum 151) are connected to each other in a non-rotatable manner by serration fitting. That is, the brake drum 151 which is replaceably mounted on the wheel body 32 is supported on the rear axle 30. Between the annular stepped portion 67 of the rear axle 30 and the fixing nut 58, an inner lace of the case-side bearing 31, a collar 69, a hub portion 135, the brake drum 151, an inner lace of the arm-side bearing 47, and a collar 71 are arranged in parallel in the axial direction and these parts are fixed to the rear axle 30 by fastening the fixing nut 58. [0043] As described above, the parking brake structure of the above-mentioned second embodiment is of a drum brake type which is provided separately from the rear brake 6 which constitutes the traveling brake on the rear wheel 104 of the motorcycle 101 and includes the brake drum 151 which is provided separately from the wheel body 132 of the rear wheel 104, wherein the brake drum 151 is replaceably mounted on the wheel body 132 and is supported on the rear axle 30. Accordingly, in the same manner as the first embodiment, a shape of the brake drum 151 and a shape of the wheel body 132 are not influenced from each other and hence, the degree of freedom in designing a brake size of the parking brake and a shape of the wheel body 132 is enhanced whereby the weight and the cost can be reduced. Further, it is possible to have the compatibility between the wheel body 132 and the brake drum 151 and hence, the generality is enhanced and the degree of freedom in selecting materials can be also enhanced. Further, the assembling and the maintenance around the rear wheel 104 can be performed easily. Further, the brake drum 151 is engaged with the rear axle 30 in serration fitting together with the rear wheel 132 and hence, it is possible to reduce the number of parts and the assembling man-hours and can suppress the weight and the cost while maintaining the reliable brake performance. [0044] Here, the present invention is not limited to the above-mentioned embodiments. For example, the first embodiment may be constituted such that the respective right-side boss portions 43 are not formed contiguously, that is, a portion of the whole periphery of the recessed portion 55 may be omitted or linings (friction materials) which are fixed to the respective brake shoes 52 may be formed on the inner periphery of the brake drum 51. Further, the brake drum 51 is not necessary an iron-made cast product or an iron-made forged product and may be made of other material such as metal, reinforced plastic, ceramic or the like having the equivalent performance. Further, in the second embodiment, by forming the brake drum 151 per se made of iron, it is not necessary to cast a drum collar 154A or a drum body 153A and hence, the wheel body 132 and the brake drum 151 can be manufactured easily. Further, in the above-mentioned embodiments, the arrangement or the shape of the disc portion 3 6 of the wheel body 32 may be exchanged in the left and right direction or may be arranged in the left-and-right symmetry. Further, the same goes for the arrangement of the brake discs 42 or the brake calipers 48 or the like. Further, the present invention is not limited to the scooter type and is also applicable to a tricycle or a four-wheeled vehicle. [0045] [Advantageous effect of the Invention] As has been explained heretofore, according to the invention described in claim 1, the degree of freedom in setting the brake size of the parking brake can be enhanced and, at the same time, the degree of freedom of the shape of the wheel body can be enhanced, whereby the weight and the cost can be reduced due to the optimum designing. Further, by constituting the wheel body and the brake drum as separate members from each other, it is possible to have the compatibility between the wheel body and the brake drum and hence, the generality is enhanced and the degree of freedom in selecting materials can be also enhanced. Further, it is unnecessary to form the wheel body together with the brake drum by casting and hence, the wheel body and the brake drum can be manufactured easily. [0046] According to the invention described in claim 2, while the wheel body and the brake drum can be individually assembled to the axle, the wheel body and the brake drum can be removed from the axle individually and hence, the assembling and maintenance around the wheel can be facilitated. [0047] According to the invention described in claim 3, the degree of freedom in setting the brake size of the parking brake can be enhanced and, at the same time, the degree of freedom of the shape of the wheel body can be enhanced, whereby the weight and the cost can be reduced due to the optimum designing. Further, by constituting the wheel body and the brake drum as separate members from each other, it is possible to have the compatibility between the wheel body and the brake drum and hence, the generality is enhanced and the degree of freedom in selecting materials can be also enhanced. Further, it is unnecessary to form the wheel body together with the brake drum by casting and hence, the wheel body and the brake drum can be manufactured easily. Further, while the wheel body and the brake drum can be individually assembled to the axle, it is possible to remove the wheel body and the brake drum from the axle individually and hence, the assembling and maintenance around the wheel can be facilitated. [0048] According to the invention described in claim 4, it is possible to connect the brake drum and the axle in a non-rotatable manner with the simple constitution and in a compact form and hence, it is possible to reduce the number of parts and the assembling man-hours and can suppress the weight and the cost while maintaining the reliable brake performance. [Explanation of symbols] 4, 104: rear wheel (wheel) 6: rear brake (traveling brake) 30: rear axle (axle) 32, 132: wheel body 51, 151: brake drum WE CLAIM: 1. A parking brake of a drum brake type which is mounted on a wheel separately from a traveling brake,, wherein in a recessed portion! formed in a wheel body of the wheel, a. brake drum which is provided as a member separate from the wheel body is arranged. 2. A parking brake as claimed in claim 1, wherein the brake drum is mounted on the wheel body and is supported on an axle of the wheel. 3. A parking brake as claimed in claim 1 wherein a brake drum, which constitutes a member separate from a wheel body of the wheel is provided, and the brake drum is mounted on the wheel body and is supported on an axle of the wheel. 4. A parking brake as claimed in claim 2 or claim 3 wherein the brake drum is engaged with the axle in serration fitting together the wheel body/. 5. A parking brake substantially as hereinbefore described with reference to the accompanying drawings.

Documents:

1356-del-2004-abstract.pdf

1356-del-2004-claims.pdf

1356-del-2004-Correspondence-Others-(30-12-2009).pdf

1356-del-2004-correspondence-others.pdf

1356-del-2004-correspondence-po.pdf

1356-del-2004-description (complete).pdf

1356-del-2004-drawings.pdf

1356-del-2004-form-1.pdf

1356-del-2004-form-19.pdf

1356-del-2004-form-2.pdf

1356-del-2004-form-3.pdf

1356-del-2004-form-5.pdf

1356-del-2004-gpa.pdf

1356-del-2004-petition-137.pdf

1356-del-2004-petition-138.pdf

1356-del-2004Form-3-(30-12-2009).pdf