WO1994005538A1

WO1994005538A1 - Apparatus for moving a carrying vehicle

Info

Publication number: WO1994005538A1
Application number: PCT/KR1993/000080
Authority: WO
Inventors: Sung In Cho
Original assignee: Sung In Cho
Priority date: 1992-09-09
Filing date: 1993-09-06
Publication date: 1994-03-17
Also published as: AU4985093A; KR940006865A; JPH07507023A; KR960009508B1

Abstract

An apparatus for moving a carrying vehicle easily and safety moves on stairs as well as on a level ground. The apparatus has rotatable belts (40) wrapping around front and rear main pulleys (21, 22) and auxiliary pulleys (23), and rotatable wheels (31, 32) mounted on shafts (11, 12) supporting the main pulleys (21, 22). The apparatus is moved by rotation of the wheels (31, 32) when moving on a level ground and moved by rotation of the belts (40) when moving on stairs.

Description

APPARATUS FOR MOVING A CARRYING VEHICLE

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates a carrying vehicle, and more particularly to an apparatus for moving a carrying vehicle which causes a carrying vehicle mounted thereon to be more easily and safely moved on stairs as well as a level ground-

Description of the Prior Art

A carrying vehicle may be generally classified into a cart for carrying a burden and a baby carriage for carrying a baby. Although the cart is useful to transfer a burden on a level ground because it is moved while its right and left wheels are rotated, the cart can not move on stairs. The baby carriage has four wheels of front and rear wheels of right and left sides for reasons of safety because it caries a baby. However, the baby carriage can not also move on stairs but move a level ground.

Therefore, a baby carriage for overcoming the above- mentioned problems is disclosed in Korean Utility Model Application No. 90-15450, which had been filed by the present applicant and thereafter obtained Korean Utility Model Publication No. 92-5319. In the baby carriage disclosed in the application, the baby carriage can move on a level ground by rotation of front and rear wheels as similar to a usual baby carriage. When the baby carriage moves on stairs, the front and rear wheels are lifted with respect to side plates by pushing lifting levers so that endless gear belts, which are wrapped about and engaged with front and rear main gear wheels and a plurality of auxiliary gear wheels supported by the side plates, come into contact with stairs. Therefore, the baby carriage can also move on stairs by means of the endless gear belt rotating about the gear wheels. Although the baby carriage can be used usefully to move on stairs, it must be mounted with the separate front and rear wheels lifted by the lifting levers and also the user must lift or lower the front and rear wheels according to conditions of the level ground and the stairs. Also, since the main gear wheels have the same diameters as those of the auxiliary gear wheels, the production cost of the baby carriage is increased and intense rolling phenomenon is generated when moving on stairs. Furthermore, the baby carriage is difficult to change its advancing course right or left.

SUMMARY OF THE INVENTION

Therefore, an object of the present invention is to overcome the above-mentioned disadvantages encountered in the prior arts and to provide an apparatus for moving a carrying vehicle which can easily and safely move on stairs as well as on a level ground without using an additional 1 ifting levers.

Another object of the invention is to provide an apparatus for moving a carrying vehicle which can change its advancing course by means of means for changing advancing course when the vehicle moves on a level ground. In accordance with the present invention, these objects can be accomplished by providing an apparatus for moving a carrying vehicle comprising: a pair of side support plates on which a carrying vehicle is mounted and which are spaced from each other; four main pulleys rotatably mounted on front and rear shaft supported between the side support plates, two of which being mounted on opposite sides of the front shaft, and the other two of which being mounted on opposite sides of the rear shaft; a plurality of auxiliary pulleys disposed between the front and rear main pulleys and rotatably mounted on the side support plates; and a pair of endless belts each of which wraps around the main and auxiliary pulleys mounted on each of the side support plates.

Either or both of the front and rear shafts are mounted with wheels at opposite sides thereof.

Either of the front and rear shafts, on which the wheels are not mounted, may be provided with means for changing an advancing course.

The side support plates may be provided with tension pulleys for adjusting tension of the belts.

Either or both od the front and rear shafts may be rotated by driving means, such as a motor.

The side support plates may be provided with means for adjusting inclination of the plates relative to a vehicle body to be mounted thereon.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the present invention will become apparent from the following description of embodiments with reference to the accompanying drawings in which:

Fig. 1 is an exploded perspective view of an apparatus for moving a carrying vehicle according to the present invention;

Fig. 2 is a front view of a course changing device of the invention;

Fig. 3A is a plan view of the apparatus of the invention which is not provided with the course changing device;

Fig. 3B is a view similar to Fig. 3A which is provided with the course changing device at its rear main shaft;

Fig. 3C is a view similar to Fig. 3A which is provided with the course changing device at its front main shaft;

Fig. 4 is a side view of a cart mounted on the apparatus of the invention; Fig. 5 is a side view of a baby carriage mounted on the apparatus of the invention;

Fig. 6A is a side view showing an operation of a cart mounted on the apparatus of the invention when it is moved on a level ground;

Fig. 6B is a side view showing an operation of a cart mounted on the apparatus of the invention, which functions as a two-wheel cart, when it is moved on a level ground;

Fig. 6C is a side view showing an operation of a cart mounted on the apparatus of the invention when it is moved up stairs;

Fig. 6D is a side view showing an operation of a baby carriage mounted on the apparatus of the invention when it is moved on a level ground;

Fig. 6E is a side view showing an operation of a baby carriage mounted on the apparatus of the invention when it is moved up stairs; Fig. 7A is a side view of the apparatus of the invention for explaining a principle of the invention;

Fig. 7B is a partial side view for explaining a principle of the invention when the a pulley has the same diameter as that of an auxiliary pulley; Fig. 7C is a partial side view of a main pulley and an auxiliary pulley of the apparatus of the invention for explaining a principle of the invention;

Fig. 7D is a partial side view of a main pulley, an auxiliary pulley and a belt of the apparatus of the invention for explaining a principle of the invention;

Fig. 8 is a plan view of a further embodiment of the invention which is provided with a motor at its front main shaft.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments according to the present invention will be now described with reference to the accompanying drawings.

An apparatus for moving a carrying vehicle according to the invention may be applied to a four-wheel cart 2 (see

Fig. 4) and a baby carriage 1 (see Fig. 5). Referring to

Fig. 1 , there is shown an apparatus for moving a carrying vehicle which is exploded. As shown in the drawing, the apparatus has a pair of side support plates 10. Each of the side support plates 10 is provided at its upper periphery with front and rear joint holes 10a and 10b for mounting a vehicle body 1 or 2 thereon. Front and rear main shafts 11 and 12 are fixed to front and rear portions of the side support plate 10. A plurality of auxiliary shafts 13 are also fixed to the side support plate 10 between the front and rear main shafts 11 and 12. A tension shaft 14 is fixed to the upper periphery of the side support plate 10 between the front and rear joint holes 10a and 10b.

The front and rear main shafts 11 and 12 are inserted in front and rear main pulleys 21 and 22, respectively. Each of the auxiliary shafts 13 are inserted in an auxiliary pulley 23 and the tension pulley 14 is inserted in a tension pulley 24. The front and rear main pulleys 21 and 22 have diameters larger than those of the auxiliary pulleys 23. The main and auxiliary pulleys 21, 22 and 23 and the tension pulley 24 are wrapped by an endless belt 40 adapted to be rotated continuously. Front and rear wheels 31 and 32 are inserted on protrusion ends of the front and rear main shafts 11 and 12 which are protruded outwardly from the side support plates 10. The front and rear wheels 31 and 32 have diameters larger than those of the front and rear main pulleys 21 and 22. In this embodiment, the main and auxiliary pulleys 21 and 22, the auxiliary pulleys 23, the tension pulley 24 and the front and rear wheels 31 and 31 are rotatably mounted on the corresponding shafts.

Referring to Fig. 2, there is shown a course changing device 54. The course changing device 54 comprises a bracket 53 fixed to either of the front and rear main shaft 11 and 12, a turning shaft 51 rotatably mounted on the bracket 53, a sub-shaft 52 transversely fixed to the lower end of the turning shaft 51 and a pair of wheels 50 rotatably mounted on the both ends of the sub-shaft 52.

Referring to Figs. 3A to 3C, there are shown three different embodiments of an apparatus of the invention. In the embodiment shown in Fig. 3A, four front and rear wheels 31 and 32 are rotatably mounted on both ends of the front and rear main shaft 11 and 12 which are protruded outwardly from the side support plates 10 similarly to Fig. 1. In the embodiment shown in Fig. 3B, the pair of front wheels 31 are rotatably mounted on the both ends of the front main shaft 11, and the course changing device 54 as shown in Fig. 2 is fixed to a middle portion of the rear main shaft 12 without the rear wheels 32. In the embodiment shown in Fig. 3C, the pair of rear wheels 32 are rotatably mounted on the both ends of the rear main shaft 12, and the course changing device 54 is fixed to a middle portion of the front main shaft 11 without the rear wheels 31.

Referring to Fig. 4, there is shown a four-wheel cart employing the apparatus according to the invention. As mentioned above, the apparatus includes the endless belts 40 wrapped around the main and auxiliary pulleys 21, 22 and 23 and the tension pulleys 23 which is adapted to move on stairs, the front and rear wheels 31 and 32 which is adapted to move on a level ground, and the course changing device 54. The four-wheel cart body 2 is mounted on the front and rear joint holes 10a and 10b of the side support plates 10 by means of connecting pins 2a. The four-wheel cart 2 has two adjusting lever 2b, and a back frame 2c and the adjusting levers 2b are formed with a plurality of setting holes 2d. Accordingly, the back frame 2c can be adjusted in its inclination by changing the connection position between the back frame 2c and the adjusting levers 2b, as required, for example, when the cart 2 moves on stairs. In this case, even though only the front wheels 31 are mounted on the front main shaft 11 without the rear wheels 32, the cart 2 can move not only on a level ground by means of its the front wheels 31 but also on stairs by means of its endless belts 40. referring to Fig. 5, there is shown a baby carriage employing the apparatus of the invention. In this case, although the baby carriage 1 may employ the apparatus without the course changing device 54 as shown in Fig. 3A, it is preferable that the baby carriage 1 employs the apparatus having the course changing device 54 in order to change easily its advancing course as shown in Fig. 3B or 3C.

Referring to Figs. 6A to 6C, there are shown the four- wheel cart moving on a level ground and stairs. Figs. 6A and 6B show the four-wheel cart 2 moving on a level ground. Although the foui—wheel cart 2 can move on a level ground by using its all four wheels 31 and 32 as shown in Fig. 6A, the cart 2 also can move on the ground by using its front wheels 31 in such a manner that the connection position between the back frame 2c and the adjusting levers 2b is changed as required, as shown in Fig. 6B. Fig. 6C shows the cart 2 moving up stairs by using its endless belt 40.

Referring to Figs. 6D and 6E, there are shown the baby carriage moving on a level ground and stairs, respectively. In Fig. 6D, the baby carriage 1 moves on the level ground by using its front and rear wheels 31 and 32. In Fig. 6E, the baby carriage 1 moves up along stairs by using its endless belt 40.

Figs. 7A to 7D illustrate a principle of the invention for preventing rolling phenomenon occurring in movement of the vehicle. As previously described, the apparatus of the invention comprises the front and rear main pulleys 21 and 22, a plurality of auxiliary pulleys 23 disposed between the front and rear pulleys 21 and 22, the endless belt 40 wrapped around the front and rear main pulleys 21 and 22 and the auxiliary pulleys 23, and the tension pulley 24 disposed between the front and rear pulleys 21 and 22 and above the auxiliary pulleys 23 which is adapted to prevent looseness of the belt 40 and adjust tension of the belt 40, as shown in Fig. 7A. The auxiliary pulleys 23 are designed to be in contact with the imaginary straight line connected between the lowest points of the front and rear main pulleys 21 and 22. The front and rear main pulleys 21 and 22 should have diameters larger than a predetermined diameter to move smoothly during movement on a level ground and stairs.

In general, a rolling amplitude of the belt 40 may vary in accordance with a distance between the front or the rear pulley 21 or 22 and the auxi iary pulley 23 and a tension of the belt 40. If the main pulley 21 or 22 and the auxiliary pulley 23 are constructed such that the main pulley 21 or 22 has the same diameter as the one of the auxiliary pulley 23, as shown in Fig. 7B, it is appreciated that the rolling amplitude "RP" of the belt 40 becomes lager and the maximum rolling amplitude "RP" may be the radius "R" of the pulley.

On the other hand, if the auxiliary pulley 23 has a diameter considerably smaller than that of the main pulley

21 or 22, as shown in Fig. 7C, the maximum rolling amplitude

"rP" of the belt 40 may be the radius "r" of the auxiliary pulley 23 but the rolling phenomenon of the belt 40 is hardly generated because the radius of the auxiliary pulley 23 is very small. Accordingly, since the auxiliary pulley 23 of the invention is designed to have a diameter considerably smaller than that of the main pulley 21 and 22, the apparatus of the invention hardly generates the rolling phenomenon.

Also, the front or the rear wheel 31 or 32 of the invention has a radius slightly smaller than a sum of a radius of the main pulley 21 or 22 and a thickness of the belt 40, as shown in Fig. 7D. For this reason, when the apparatus of the invention moves on a level ground, the apparatus is subjected to a little load because it moves by the rotation of the wheels 31 and 32. When the apparatus of the invention moves on stairs by pushing or pulling a vehicle mounted thereon, the front wheel 31 is first caught on a corner of a corner and then the belt 40 is mounted on the corner but the apparatus hardly generates the rolling phenomenon because a difference between the outer circumference of the wheel and the outer surface of the belt is very small . Therefore, even though the front and rear wheels 31 and 32 are not separately lifted with respect t the belt 40, the apparatus of the invention can move on stairs as well as a level ground.

Referring to Fig. 8, there is shown a further embodiment of the invention. In the embodiment, the front or the rear main shaft 11 or 12 is connected to a motor "M". A driving shaft "MS" of the motor "M" is fixed with a driving gear "Ma" and the main shaft 11 or 12 is fixed with a driven gear 11a. The driving gear "Ma" is engaged with the driven gear 11a, so that the main shaft 11 or 12 is rotated by the motor "M". Operation of the above-constructed apparatus of the present invention will be described hereinafter.

When a vehicle, such as a cart, is moved on a level ground, as shown in Figs. 6A and 6B, the endless belts 40 are not in contact with the ground but the front and rear wheels 31 and 32 come into contact with the ground. When the cart 2 is intended to be used as a two-wheel cart, the connection position between the back frame 2c and the adjusting lever 2b can be appropriately changed according to a height of the user and a condition of a burden. Hence, the cart 2 can be more easily moved by only rotation of the front wheels 31.

On the other hand, when the vehicle 2 is moved up and down stairs, as shown in Fig. 6C, the user adjust an inclination of the vehicle 2 by a manipulation of the adjusting lever 2b according to a condition of the sta rs and then grips a handle portion and draws up the vehicle 2. Therefore, the vehicle 2 can be moved up the stairs by the rotation of the endless belt 40. In this case, if the user operates the motor "M" connected to the main shaft 11 , the user can easily move up the vehicle 2 without dissipation of much effort. Although the apparatus as shown in Fig. 8 incorporates the motor "M" therein, it does not consume much electric power because the motor "M" is operated only when the vehicle is moved up stairs. Similarly to above case, the apparatus of the invention may be applied to a vehicle, such as a baby carriage, as shown in Figs. 6D and 6E. When the baby carriage 1 is moved on a level ground, as shown in Fig. 6D, it can be easily moved since the ground is in contact with not the endless belt 40 but the front and rear wheels 31 and 32. When the baby carriage 1 is moved up and down stairs, it is also easily moved by the rotation of the endless belt 40. Particularly, if the baby carriage employs the embodiment shown in Fig. 8, the baby carriage can be more easily moved up the stairs by means of the drive of the motor "M".^*

Since the apparatus of the invention incorporates a plurality of auxiliary pulleys 23 having diameters considerably smaller than those of the main pulleys 21 and 22, it is subjected to a little load. Even though it is assumed that the maximum rolling phenomenon is generated when the apparatus comes into contact with a corner portion of a step, the maximum rolling amplitude can not exceed the radius of the auxiliary pulley 23. Therefore, the cart 2 employing the apparatus of the invention can safely carry a burden without damage of the burden, and the baby carriage 1 can comfortably carry a baby. Also, since the apparatus of the invention is constructed such that the front and rear wheels 31 and 32 having diameters slightly larger those of the front and rear main pulleys 21 and 22 are mounted on the front and rear main shaft 11 and 12 supporting the main pulleys 21 and 22, the front and rear wheels 31 and 32 are rotated together with the belt 40 and thus the main pulleys 21 and 22. More specifically, since the front and rear wheels 31 and 32 have diameters slightly larger than the sum of the front or the rear pulley 21 or 22 and the thickness of the belt 40 wrapped around the pulley, rolling phenomenon is hardly generated during movement. Also, since only the front and rear wheels 31 and 32 are in contact with a ground when moving on a level ground, the endless belts 40 are not subjected to a load, so that the vehicle can be easily moved on the ground. Even though there is a protrusion on the ground, the vehicle can be easily moved without difficulty because the front and rear wheels 31 and 32 are rotated together with the belts 40.

In addition, since the apparatus of the invention incorporates the course changing device 54 as shown in Fig. 2, it is easy to change its advancing course even in a baby carriage.

As apparent from the above description, since the apparatus for moving a carrying vehicle of the invention is moved by the rotation of the endless belts when moving up and down stairs and moved by the rotation of the front and rear wheels when moving on a level ground, the apparatus can be moved on stairs as well as a level ground. Also, since rolling phenomenon is hardly generated in the apparatus of the invention during movement on a level ground and stairs, a vehicle mounted on the apparatus can safely and comfortably carry a burden or a baby. Therefore, the apparatus for moving a carrying vehicle according to the invention can provide the user excellent convenience.

Although the preferred embodiments of the invention have been disclosed for illustrative purpose, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

WHAT IS CLAIMED IS:

1. An apparatus for moving a carrying vehicle comprising: a pair of side support plates on which a carrying vehicle is mounted and which are spaced from each other; four main pulleys rotatably mounted on front and rear shaft supported between the side support plates, two of which being mounted on opposite sides of the front shaft, and the other two of which being mounted on opposite sides of the rear shaft; a plurality of auxiliary pulleys disposed between the front and rear main pulleys and rotatably mounted on the side support plates; and a pair of endless belts each of which wraps around the main and auxiliary pulleys mounted on each of the side support plates.

2. An apparatus in accordance with Claim 1, wherein said apparatus further comprises a pair of front wheels which have diameters larger than those of said front pulleys and which are rotatably mounted on opposite sides of said front shaft supporting said front pulleys.

3. An apparatus in accordance with Claim 1, wherein said apparatus further comprises a pair of rear wheels which have diameters larger than those of said rear pulleys and which are rotatably mounted on opposite sides of said rear shaft supporting said rear pulleys.

4. An apparatus in accordance with Claim 2 or 3, wherein either of said front and rear shafts, on which said wheels are not mounted, is provided with means for changing an advancing course.

5. An apparatus in accordance with Claim 1, wherein said side support plates are provided with tension pulleys for adjusting tension of said belts.

6. An apparatus in accordance with Claim 1, wherein said apparatus further comprises driving means for rotating either of both of said front and rear shafts.

7. An apparatus in accordance with Claim 1 , wherein said side support plates are mounted with a baby carriage body.

8. An apparatus in accordance with Claim 1, wherein said side support plates are provided with means for adjusting inclination of said plates relative to a vehicle body to be mounted thereon.