Technical Field

The subject invention relates to a wheel, and more particularly to a shock-absorbing wheel, its construct being greatly 5 improved by means of a shock-absorbing device which can better absorb and set off the shock received by the wheel.

The subject invention can be applied to all such wheels as those of bicycles, hand carts, and all other vehicles for transportation.

ι o Background Art

Various arts of easing the shock received by the wheel from road surfaces, while running, have been developed and are publicly known. But most of them consist in devices with certain absorbers (elastic members) placed between the body and the revolving shaft

1 5 of a vehicle, and so these conventional means are not always able to effectively offset the shock relayed to the wheel.

Korean Utility Model Reg. No. 65458, the registrant being the very same author of the subject invention, comprises a moving member, which has a shaft bore and is fitted in the frame of the 20 wheel, said moving member getting joined with elastic members with said frame of the wheel in the radial direction. In this prior art, however, the loop portion of both ends of the elastic member, that is, the coil spring, is bent in the direction perpendicular to the

other part of the coil spring in order to form a hook. Both ends of the elastic members are joined with the hub of the moving member and frame of wheel each other by bolts, but the portion bent and disfigured to form said hook is likely to bear by itself a concentrated stress, and so is easily to break under the fatigue from said concentrated stress. A serious problem inherent in this prior art.

Korean Utility Model Application. No. 94-30606, also of the same author of the subject invention, relates to a construction, wherein the frame of the wheel extends from the rim so that a round moving member which has a hub can be put between a pair of wheel frames facing each other and a rim made of a pair of half rims. The half rims are formed in a body with the wheel frames, joined together by appropriate means including fastening with bolts or welding, for example, so that space for moving of the moving member may be secured between the pair of wheel frames. But this invention also has a problem in that the rim, made of a pair of half rims, can be severed in two, when it is in use in combination with a pneumatic tire and is subjected to heavy load.

Korean Utility Model Application. No. 95-13305, also of the same author of the subject invention, seemed to have solved these problems, but is not yet free of problems. When a vehicle is driven on a very steep and uneven road, the motion up, down, right, and left of the moving member gets big and rough entailing a big and rough motion of the coil springs stretched radially between hub and wheel frame, causing the coil spring to roll up if it is too long or its elasticity is too small, such a phenomenon, when aggravated, being

likely to result in its early damage, while the big and rough motion of the moving member usually delays conveyance of power through the shaft.

Now the objective of the subject invention is to solve all such problems, by providing a moving member with wings or projections which are to work together with a plurality of second bores formed in the wheel frame in a mutual control action to keep the moving member from exceeding motion up, down, right, and left; by providing the joint portion of the elastic members with a strong and firm joining device to keep it from damage under overloading; and, in fine, by providing a shock-absorbing wheel free of severance of said pair of half rims even under exceeding overload upon them.

Disclosure of Invention

According to an embodiment of the subject invention, it is so arranged, in fitting a pair of wheel frames on the rim where a pneumatic tire is mounted, that said pair of wheel frames have a first bore in the center, a plurality of second bores which are regularly formed along the circumference of said first bore and have a smaller diameter than that of said first bore and the circumferential face of second bore being inwardly bent toward the inside of said frames. A plurality of projections sticking up and down are regularly formed along the outer circumference of a moving member, or said moving member has a plurality of wings.

Each of said projections may be positioned inside of said second bores and each wing may be positioned between said second bores.

By these all it is made possible to control exceeding motion up,

down, right, and left of said moving member and prevent possible delay of conveyance of power through a mutual restraint of said projections or wings on said moving member and inwardly bent circumferencial face of said second bores. Even if the elasticity of the coil spring is not much, its abrupt early damage can be prevented.

In the subject invention the rim on which the tire is fitted is made in a single body, the center of its inner side being formed in a flange, on which a pair of frames are fastened leaving space for said moving member to move, whereby said rim does not disfigure even though strong load burdens it through a pneumatic tire.

In another embodiment of the subject invention a single wheel frame with a first bore is formed inside a tire rim in a unitary structure. A pair of moving members are so fitted on a hub placed in said first bore as to be placed on each side of said wheel frame. A plurality of elastic members are fitted between the inner circumference of said tire rim and the outer circumference of said moving member to stuff and close up the idle space, also making it possible to use elastic members of shorter length, too.

In still another embodiment of the subject invention a cover board can be attached to a spiral bar for protection of the coil spring with a view to the prevention of entry of foreign subsubstance in the coil spring placed on the outside of said wheel frame.

In the subject invention, coil springs may be used as elastic members, and by joining the coil springs which extend between said wheel frame and said hub by the use of the spiral structure of said coil springs themselves. The alteration of a portion for fastening is dispensed with, whereby a means is provided for prevention of overburdening by concentration of stress.

The various objectives and advantages of the subject invention will be clear from the description following the list of drawings below.

Brief Description of Drawings

Fig. 1 is a frontal view to illustrate the first embodiment of the subject invention,

Fig. 2 is a sectional view of Fig. 1,

Figs. 3 is a partial sectional view of Fig. 1,

Fig. 4-A and 4-B are drawings to illustrate the operation of

Fig. 1,

Fig. 5 is a perspective view of the male and female keepers in the first embodiment of the subject invention,

Fig. 6 is a frontal view to illustrate the first embodiment of the subject invention without keepers,

Figs. 7 is a sectional view of Fig. 6,

Fig. 8 is a frontal view to illustrate the second embodiment of the subject invention,

Fig. 9 is a sectional view of Fig. 8,

Fig. 10 is an enlarged sectional view of a rim in the subject invention,

Fig. 11 is an enlarged sectional view of a rim of conventional arts,

Fig. 12 is a perspective view of the spring-joiner in the subject invention,

Fig. 13 is a sectional view showing a cover board attached in Fig. 2,

Fig. 14 is a frontal view of the third embodiment,

Fig. 15 is a sectional view of Fig. 14,

Fig. 16 is a perspective view of a prior art,

Fig. 17 is a sectional view of a prior art.

Best Mode for Carrying out the Invention According to a first embodiment of the invention, as shown in Fig. 1-4, a pair of wheel frames 14, 14' are mounted on the inside of a rim 12 where a pneumatic tire 10 is mounted. A pair of wheel frames 14, 14' have a first bore 16 in the center and a plurality of second bores 18 formed regularly and circularly above said first bore 16. The arranged positions of said second bores 18 are removed for a certain distance from, but are along the circumference of said first bore 16. Here, said second bores 18 have a smaller diameter than that of said first bore 16, and the circumferential faces of said second bores 18 are inwardly bent toward the inside of said frames 14, 14'. A moving member 30 with a plurality of wings 70 is positioned between said frames 14, 14', and here a hub 34 is attached to the center of said moving member 30, positioned inside said first bore 16. Each of said wings 70 of said moving member 30 is positioned respectively between said second bores 18. A plurality of elastic members 40 are joined radially with each other between the inside of said rim 12 and said hub 34. By these all, exceeding movement of said moving member 30 can be prevented by restraint of the outer surface of these wings 70 against the inwardly bent circumferential face of said second bores, at the time when said moving member 30 moves. It is made possible to prevent delay of conveyance of power, also. A flange 100 is formed as a unitary structure in the center of the inside of said rim 12, through which a plurality of spiral bars 60 are passed. Said wheel frames 14, 14' are attached to said spiral bars 60. The outside joiners of said elastic members are fastened to both ends of said spiral bars with nuts 50, while the inside joiners of said elastic

members 40 are joined with said hub 34 by bolts 52. Both frames 14, 14' can be fixed tight by joining said second bores 18 on both said frames 14, 14' with male and female keepers 20, 20'.

Figs. 4-a and 4-b show the ways of operation of said moving member 30 and said second bores 18 in the subject invention.

Fig. 4-b-l shows how said moving member 30 is positioned in the center of said wheel, Fig. 4-b-2 shows how said wings 70 of said moving member 30 are caught on the outer circumference of said second bores 18 while said moving member is moving leftward, and Figs. 4-b-3, 4-b-4, and 4-b-5 show how said wings of said second bores operate while said moving member moves right, up, and downward, respectively.

Fig. 5 shows said male and female keepers 20, 20' which fasten both said frames 14, 14' tightly through said second bores 18. Whereby, shaking or severance of said frames 14, 14' can be prevented even if a great deal of load bears down on them, and thus a still better strength can be maintained.

Figs. 6 and 7 illustrate the first embodiment of the subject invention with none of said male and female keepers applied thereto.

According to a second embodiment of the invention, as shown in Fig. 8-9:

A pair of wheel frames 14, 14' are mounted on the inside of a rim 12 where a pneumatic tire 10 is mounted. Said round frames have a first bore 16 in the center. There are a plurality of second bores 18 arranged regularly above said first bore. Said second bores have a smaller diameter than the diameter of said first bore. The circumferential face of second bore is inwardly bent toward the inside of said frames 14, 14'. A round moving member having projections 72 is positioned between said pair of frames 14, 14'. A hub 34 is attached to the center of said round moving member 30' with projections 72 and positioned inside said first bore 16, while said moving member has projections up and down along its outer circumference in positions corresponding with said second bores 18. As a result, exceeding motion of said moving member 30' can be placed under control through restraint of said projections 72 with the internally bent inner surface 110 of said second bores. A plurality of elastic members 40 are joined radially together between the inside of said rim 12 and said hub 34. There in the center of the inside of said rim 12 a flange 100 is formed as a unitaty structure, through which a plurality of spiral bars 60 are passed, to which spiral bars 60 are said pair of wheel frames attached. Both ends of said spiral bars are fastened on end joiners of said elastic member by nuts 50, while the joiners of said elastic member are fastened with said hub by bolts 52.

Fig. 10 is the enlargement of a drawing of the inner central portion of a rim 12, where a flange 100 is formed as a unitary structure, while Fig. 11 shows the inner central portion of a rim, which is not formed as a unitary structure. Fig. 11 shows that a

short flange 100 is formed in the inner central portion of said rim 12 as a unitary structure. A plurality of spiral bars 60 are passed through said flange 100. The spiral bars 60 are joined with said wheel frames 14, 14'. The outer joiners of coil springs 40 are fixed on both ends of these spiral bars by nuts 50. As is described above, said rim is formed in a single body. Therefore, said rim is not disfigured even when heavy load is applied on it through the pneumatic tire 10 fitted to it. And as this flange 100 is formed in an internal extension of said rim as a unitary structure with it, there emerges space on either side for motion of said moving member 30 and for admission of a pair of frames, whereupon, the production itself is facilitated that much. In especial, said spiral bars 60 used in fastening said frame to said flange of said rim can facilitate attachment together of said joiners of said elastic members 40 joined radially.

Fig. 12 shows a coil spring 40', an example of said elastic member 40 usable in the subject invention, and its joiner 42 also.

Coil springs 40' can be used in the subject invention.

But when coil springs 40' are joined in the radial direction between said frames 14, 14' and said moving member 30 which moves inside said pair of frames, the shock-absorbing springs are likely to suffer from, and break under, the concentrated stress on the joint portions.

In other words, when such coil springs 40' are used, the loop on an end is bent perpendicularly to another part of coil spring to form a hook, and such a hook is fastened with said wheel frames 14, 14' and said hub 34 of said moving member 30 by bolts; the stress is naturally concentrated on the portion of the loop shaped by bending, the portion suffering more than any other portions do, and results in an easy breach. A serious shortcoming this is.

The subject invention has been made to avoid such shortcomings also. Coil springs 40' extended between said wheel frames 14, 14* and said hub 34 of said moving member 30 are provided with an internal spiral structure 48, instead of their ends getting bent. And the spiral bars 60 to be spirally joined therewith are fastened spirally by spiral joiners 42 having holes 46 for passage of bolts between said wheel frame and said hub with bolts and nuts respectively.

Accordingly, because the ends of said coil springs are not mechanically disfigured for fastening, there are no phenomena of fatigue to occur to them, and thus the wheel can have long and steady effects of shock-absorption.

As a matter of course, for elastic members 40 in the subject invention various materials of elasticity such as urethane can also be made use of, aside from coil springs 40'.

Fig. 13 shows how cover boards 110 for protection of coil springs 40', positioned outside the wheel frames 14, 14', are

fastened tight with spiral bars, and these cover boards 110 help prevent foreign substances from entry in coil springs.

Figs. 14 and 15 show the third embodiment of the subject invention. This embodiment is of a construct, wherein a wheel frame 14" with a first bore 16 is formed in the center of the inside of a tire rim 12 as a unitary structure. A hub 34 to be attached to the axle (not shown in the drawing) of a vehicle is positioned in said first bore 16. A plurality of elastic members 40 are connected between said rim 12 and said hub 34. A pair of moving members 30", which have a larger diameter than that of said first corresponding bore 16 and positioned respectively on both outsides of said wheel frame 14", are mounted on said hub 34. Elastic members 40 are joined between the inner circumference of said rim and the outer circumference of said moving member.

The subject invention, as has been described above, has advantages in that said wheel frame 14" is a single one, and said moving member 30" fitted on said hub 34 and joined with said rim 12 by elastic members 40 is positioned on both surfaces of said wheel frame 14". Therefore, there is no closed moving space between said wheel frame 14" and said moving member 30", and foreign substances can easily drop off if they actually happen to enter there, while the length of said elastic members 40 can be shorter than otherwise because they are connected between the outer edge of said moving member 30" and the rim of said tire.

The subject invention, as has been described above, can be applied to all such wheels as those of toys, bicycles, hand carts, and all other vehicles for transportation, and although the invention has been described for just these several embodiments, many a possible variation is deemed obvious to all with ordinary skills in the specific field of industry.

Accordingly, the invention as described in what is claimed actually includes all possible variations from the point of view of prior arts, and, therefore, should be interpreted as broadly as can be.