Double eccentric type caster

Abstract

The present invention relates to a double eccentric type caster, in which a double eccentric rotor is configured to rotate around two pivoting portions, that is, the vertical center line of an upper shaft and the vertical center line of a lower shaft, so as to reduce the radius of rotation, and moreover, to prevent a cart from escaping from a progressing passage and prevent shaking of the cart, thereby safely transporting a heavy object (transport object). Moreover, as the cart is rotated around the two pivoting portions, a user does not need to exert a lot of force to rotate the cart, and it is very convenient to use the cart.

Description

Double eccentric caster

[0001] The present invention relates to a double eccentric caster, and more particularly, to a double eccentric caster in which a double eccentric rotor is configured to rotate around two pivot points, that is, the vertical center line of an upper shaft and the vertical center line of a lower shaft, thereby reducing the turning radius of a cart (or an unmanned guided vehicle) and preventing the cart from deviating from a travel path, and effectively preventing the cart from shaking when moving, thereby ensuring the safety of transporting the cart.

[0002] Generally, casters are installed on the bottom of a cart (or unmanned guided vehicle) for moving heavy objects (cargo) to enable the cart to be moved easily.

[0003] The caster is composed of a fastening plate that enables installation on the bottom of a bogie, a caster body that is rotatably connected to the fastening plate, and a moving wheel that is installed on the caster body.

[0004] The fastening plate has a number of connecting holes (bolt holes) formed so that it can be connected to the bottom surface of the bogie, and the caster is fixedly installed on the bottom surface of the bogie by fastening bolts to the connecting holes.

[0005] The caster body that is coupled to the fastening plate is installed using a bearing as a medium, and is configured so that when the caster turns, the caster body rotates with one turning part based on the center of the bearing.

[0006] However, since conventional casters rotate with a single turning part, the turning radius increases when turning, and the bogie shakes and the bogie deviates from the travel path, which has the disadvantage of compromising the safety of transportation.

[0007] In particular, conventional casters have the disadvantage of being very inconvenient to use because the user needs a lot of force to turn the cart as it rotates around one pivot point.

[0008] The present invention has been invented to solve the above-mentioned problem, and its purpose is to provide a double eccentric caster that is very convenient to use because it is configured so that a double eccentric rotating body rotates around two pivot points, the vertical center line of an upper shaft and the vertical center line of a lower shaft, thereby reducing the turning radius of a cart (or an unmanned guided vehicle), preventing the cart from deviating from a traveling path, and preventing the cart from shaking, thereby safely transporting heavy objects (carrying objects), and because the cart rotates around two pivot points, the user does not need to use much force to rotate the cart.

[0009] In order to achieve the above object, a double eccentric caster according to a preferred embodiment of the present invention comprises: a base fixing plate fixedly installed on the lower surface of a bogie; a caster body rotatably connected to the base fixing plate; and a movable wheel rotatably installed on the caster body about a shaft (rotating axis or rotating pin). In a caster having an eccentric body, an upper shaft formed on the upper side of the eccentric body and installed on the fastening plate via an upper bearing, and a lower shaft formed on the lower side of the eccentric body and installed on the caster body via a lower bearing, there is a technical feature that the caster is configured to rotate at two pivot points by positioning the vertical center line (L1) of the upper shaft and the vertical center line (L2) of the lower shaft to be eccentric.

[0010]

[0011] Additionally, the upper shaft and the lower shaft are configured such that their axle centers are spaced apart.

[0012]

[0013] In addition, the vertical center line (L1) and the vertical center line (L2) may be spaced apart by, for example, 20 mm, and the vertical center line (L2) and the vertical line (L3) of the shaft (rotation axis) of the moving wheel may be spaced apart by, for example, 10 mm.

[0014]

[0015] In addition, the double eccentric rotor is configured to reduce the radius of rotation by rotating at two pivot points of the vertical center lines (L1, L2).

[0016]

[0017] In addition, an upper bearing support step for supporting the upper bearing may be formed on the upper surface of the eccentric body in contact with the outer surface of the upper shaft, and a lower bearing support step for supporting the lower bearing may be formed on the lower surface of the eccentric body in contact with the outer surface of the lower shaft.

[0018]

[0019] Meanwhile, a double eccentric caster according to a first modified example of the present invention has a technical feature in that a first insertion hole is formed by interposing an upper bearing in the center of a fastening plate to insert the upper shaft, a finishing cap (end cap) is fastened to the first insertion hole, a support shaft is installed between the upper shaft and the finishing cap to support the upper end of the upper shaft, and the support shaft is installed to be rotatably installed by a support bearing.

[0020]

[0021] A support shaft support portion having a support mounting groove is formed protrudingly on the lower surface of the above-mentioned closing cap and the upper surface of the above-mentioned upper shaft, and a support bearing support step for supporting the support bearing is formed on the bottom surface of the above-mentioned support mounting groove so that both ends of the support shaft do not come into contact with the bottom surface of the above-mentioned support mounting groove.

[0022]

[0023] Furthermore, a lubricant storage space may be formed between the closing cap and the fastening plate, and a lubricant passage may be formed inside the double eccentric rotor.

[0024]

[0025] Meanwhile, a double eccentric caster according to a second modified example of the present invention has a technical feature in that ratchet teeth are formed on the outer surface of the lower shaft and the inner surface of the upper bearing to prevent them from being arbitrarily separated after being combined when the upper shaft and the lower shaft are inserted into the upper bearing and the lower bearing.

[0026] A key groove is formed on the upper surface of the upper bearing and the upper shaft and on the lower surface of the lower bearing and the lower shaft, and a key is configured to be fastened within the key groove.

[0027] In this way, the present invention has the following effects.

[0028] First, upper and lower bearings are installed on the inner periphery of the fastening plate and the caster body, respectively, to ensure smooth rotation of the double eccentric rotor. Since the double eccentric rotor is configured to rotate around two pivot points, the vertical center line of the upper shaft and the vertical center line of the lower shaft, the turning radius is reduced, and the cart does not deviate from the travel path, and the cart can be prevented from shaking, enabling the safe transport of heavy loads (carrying items).

[0029] Second, it is very convenient to use because the user does not need to use much force to turn the bogie as it rotates around two pivot points.

[0030] Third, in the structure of the double eccentric rotor, bearing support steps are formed at each of the upper and lower ends of the body to support the bearings, thereby stably supporting the load of the weight loaded on the bogie.

[0031] Figure 1 is a perspective view showing a bogie having a double eccentric caster according to a preferred embodiment of the present invention.

[0032] Figure 2 is a perspective view showing a double eccentric caster according to a preferred embodiment of the present invention.

[0033] Figure 3 is a bottom perspective view showing a double eccentric caster according to a preferred embodiment of the present invention.

[0034] Figure 4 is a front view showing a double eccentric caster according to a preferred embodiment of the present invention.

[0035] Figure 5 is a bottom view showing a double eccentric caster according to a preferred embodiment of the present invention.

[0036] Figure 6 is an exploded perspective view showing a double eccentric caster according to a preferred embodiment of the present invention.

[0037] Figure 7 is a perspective view of a part of Figure 6.

[0038] Figure 8 is a longitudinal cross-sectional view showing a double eccentric caster according to a preferred embodiment of the present invention.

[0039] Figure 9 is an exploded perspective view showing a double eccentric rotor and upper and lower bearings in a double eccentric caster according to a preferred embodiment of the present invention.

[0040] FIG. 10 is a perspective view illustrating the combination of a double eccentric rotor and upper and lower bearings in a double eccentric caster according to a preferred embodiment of the present invention.

[0041] Figure 11 is a longitudinal cross-sectional view showing the combination of a double eccentric rotor and upper and lower bearings in a double eccentric caster according to a preferred embodiment of the present invention.

[0042] Figure 12 is a drawing sequentially showing a state in which the direction of travel of a double eccentric caster according to a preferred embodiment of the present invention is changed.

[0043] Figure 13 is a bottom view of Figure 12.

[0044] Figure 14 is a drawing sequentially showing the turning state of a double eccentric caster according to a preferred embodiment of the present invention.

[0045] Figures 15 and 16 are an exploded perspective view and a longitudinal cross-sectional view showing a double eccentric caster according to a first modified example of the present invention.

[0046] Figure 17 is an enlarged view of the main part of Figure 16.

[0047] Figures 18 and 19 are an exploded perspective view and a longitudinal cross-sectional view showing a double eccentric caster according to a second modified example of the present invention.

[0048] Fig. 20 is a plan view showing the combination of the double eccentric rotor and the upper and lower bearings in a double eccentric caster according to a second modified example of the present invention.

[0049] Fig. 21 is a longitudinal cross-sectional view showing the combination of the double eccentric rotor and the upper and lower bearings in a double eccentric caster according to a second modified example of the present invention.

[0050] Hereinafter, a double eccentric caster according to a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0051] FIG. 1 is a perspective view showing a bogie having a double eccentric caster according to a preferred embodiment of the present invention, FIG. 2 is a perspective view showing a double eccentric caster according to a preferred embodiment of the present invention, FIG. 3 is a bottom perspective view showing a double eccentric caster according to a preferred embodiment of the present invention, FIG. 4 is a front view showing a double eccentric caster according to a preferred embodiment of the present invention, FIG. 5 is a bottom view showing a double eccentric caster according to a preferred embodiment of the present invention, FIG. 6 is an exploded perspective view showing a double eccentric caster according to a preferred embodiment of the present invention, FIG. 7 is an exploded perspective view showing an excerpt of a main part of FIG. 6, and FIG. 8 is a longitudinal sectional view showing a double eccentric caster according to a preferred embodiment of the present invention.

[0052] And FIG. 9 is an exploded perspective view showing a double eccentric rotor and upper and lower bearings in a double eccentric caster according to a preferred embodiment of the present invention, FIG. 10 is a combined perspective view showing the combination of a double eccentric rotor and upper and lower bearings in a double eccentric caster according to a preferred embodiment of the present invention, and FIG. 11 is a longitudinal cross-sectional view showing the combination of a double eccentric rotor and upper and lower bearings in a double eccentric caster according to a preferred embodiment of the present invention.

[0053] First, referring to FIGS. 1 to 8, a double eccentric caster (100) according to a preferred embodiment of the present invention comprises a fastening plate (110) fixedly installed on the lower surface of a cart (or unmanned guided vehicle) (10); a caster body (120) rotatably connected to the fastening plate (110); and a moving wheel (130) rotatably installed on the caster body (120).

[0054] The above-mentioned fastening plate (110) is formed with a number of fastening holes (bolt holes) (111) so that it can be fastened to the bottom surface of the bogie (10), and a bolt (113) is fastened to the fastening holes (111) so that the caster (100) is fixedly installed on the bottom surface of the bogie (10).

[0055] A double eccentric caster (100) according to a preferred embodiment of the present invention comprises a double eccentric rotating body (140) comprising a double eccentric main body (143), an upper shaft (141) formed on the upper side of the eccentric main body (143) and installed on a fastening plate (110) via an upper bearing (B1), and a lower shaft (142) formed on the lower side of the eccentric main body (143) and installed on a caster body (120) via a lower bearing (B2).

[0056] The above moving wheel (130) is rotatably installed on the caster body (120) by a shaft (hinge pin) (131).

[0057] The above double eccentric rotor (140) is configured to rotate at two pivot points so that the vertical center lines (L1, L2) (shown in FIG. 8) of the upper shaft (141) and the lower shaft (142) are eccentric to each other.

[0058] The above double eccentric rotor (140) is configured to rotate around two pivot points, i.e., the vertical center line (L1) of the upper shaft (141) and the vertical center line (L2) of the lower shaft (142), thereby reducing the rotation radius, thereby preventing the bogie (10) from deviating from the travel path and preventing the bogie (10) from shaking, thereby enabling the safe transport of heavy objects (carrying objects).

[0059] The upper shaft (141) and the lower shaft (142) are configured so that their axes are spaced apart. That is, the vertical center lines (L1, L2) are configured so that they are spaced apart. The distance between the vertical center line (L1) and the vertical center line (L2) can be, for example, 20 mm. In addition, the distance between the vertical center line (L2) and the vertical line (L3) of the shaft (131) of the moving wheel (130) can be configured so that they are spaced apart, for example, 10 mm.

[0060]

[0061] Meanwhile, with further reference to FIGS. 9 to 11, the structure of the double eccentric rotor (140) will be described in more detail.

[0062] According to a preferred embodiment of the present invention, a double eccentric rotor (140) has an upper shaft (141) formed on the upper side of a body (143) and a lower shaft (142) formed on the lower side of the body (143). The upper shaft (141) and the lower shaft (142) are positioned so that their vertical center lines (L1, L2) (shown in FIG. 8) are eccentric with each other, and are configured to rotate at two pivot points of the vertical center lines (L1, L2).

[0063] An upper bearing support step (141a) for supporting an upper bearing (B1) is formed on the upper surface of the eccentric body (143) in contact with the outer surface of the upper shaft (141), and a lower bearing support step (141b) for supporting a lower bearing (B2) is formed on the lower surface of the eccentric body (143) in contact with the outer surface of the lower shaft (142), thereby allowing the upper and lower bearings (B1, B2) to be installed more stably, and allowing the double eccentric caster (100) to stably support the load of a heavy object loaded on the carriage (10).

[0064]

[0065] In addition, FIG. 12 is a drawing sequentially showing a state in which the direction of travel of a double eccentric caster according to a preferred embodiment of the present invention is changed, and FIG. 13 is a bottom view of FIG. 12.

[0066] Referring further to FIGS. 12 and 13, arrow (A) indicates the direction of travel of the double eccentric caster (100), and arrow (B) indicates the direction of rotation of the moving wheel (130). When the double eccentric caster (100) is moved to the left and then changes direction to the right, the caster body (120) rotates and the double eccentric rotor (140) rotates at the same time, changing the direction of the moving wheel (130) so that it turns in a small radius.

[0067] That is, by the double eccentric rotor (140), the caster body (120) has two pivot points that are each rotated at an eccentric position with respect to the fastening plate (110), so that the double eccentric caster (100) rotates at a relatively smaller radius than a conventional caster having one pivot point (see FIG. 8).

[0068]

[0069] And Fig. 14 is a drawing sequentially showing the turning state of a double eccentric caster according to a preferred embodiment of the present invention.

[0070] Referring further to FIG. 14, a double eccentric caster (100) according to a preferred embodiment of the present invention has two pivot points on the vertical center lines (L1, L2) when turning, and the radius of rotation becomes smaller as it rotates (see FIG. 8).

[0071] That is, the upper shaft (141) of the double eccentric rotor (140) is installed and rotated on the fastening plate (110) using the upper bearing (B1) as a medium, and the lower shaft (142) of the double eccentric rotor (140) is installed and rotated on the caster body (120) using the lower bearing (B2) as a medium at a position eccentric from the central position where the double eccentric rotor (140) is coupled to the fastening plate (110), thereby rotating eccentrically. Therefore, the double eccentric caster (100) of the present invention rotates at a relatively smaller radius than a conventional caster having one turning portion.

[0072]

[0073] Meanwhile, FIGS. 15 and 16 are an exploded perspective view and a longitudinal cross-sectional view illustrating a double eccentric caster according to a first modified example of the present invention, and FIG. 17 is an enlarged view of a main part of FIG. 16.

[0074] Referring to FIGS. 15 to 17, a double eccentric caster (200) according to a first modified example of the present invention comprises a fastening plate (110) fixedly installed on the lower surface of a cart (or unmanned guided vehicle) (10) (see FIG. 1); a caster body (120) rotatably connected to the fastening plate (110); and a moving wheel (130) rotatably installed on the caster body (120).

[0075] A first insertion hole (110a) is formed in the center of the above-mentioned fastening plate (110) for inserting an upper shaft (141) through an upper bearing (B1), and a closing cap (150) is fastened to the first insertion hole (110a).

[0076] Between the upper shaft (141) and the closing cap (150), a support shaft (160) is installed to support the upper portion of the upper shaft (141), and the support shaft (160) is installed to be rotatable by a support bearing (B3).

[0077] A support shaft support portion (161) having a support mounting groove (160a) is formed protrudingly on the lower surface of the above-mentioned closing cap (150) and the upper surface of the above-mentioned upper shaft (141), and a support bearing support step (160b) for supporting a support bearing (B3) is formed on the bottom surface of the support mounting groove (160a) so that both ends of the support shaft (160) do not come into contact with the bottom surface of the support mounting groove (160a).

[0078] Furthermore, a lubricant storage space (170) is formed between the closing cap (150) and the fastening plate (110), and a lubricant passage (171) is formed inside the double eccentric rotor (140).

[0079] In the double eccentric caster (200) according to the first modified example of the present invention configured as described above, the support shaft (160) is installed so as to be rotatable by the upper and lower bearings (B1, B2) as well as the support bearing (B3), so that the support shaft (160) does not shake and the rotation of the support shaft (160) can be implemented more stably.

[0080] And, by supplying lubricating oil to the upper and lower bearings (B1, B2) through the lubricating oil passage (171), smooth rotation of the support shaft (160) can be ensured.

[0081]

[0082] Meanwhile, FIGS. 18 and 19 are an exploded perspective view and a longitudinal cross-sectional view illustrating a double eccentric caster according to a second modified example of the present invention.

[0083] FIG. 20 is a plan view showing the combination of a double eccentric rotor and upper and lower bearings in a double eccentric caster according to a second modified example of the present invention, and FIG. 21 is a longitudinal cross-sectional view showing the combination of a double eccentric rotor and upper and lower bearings in a double eccentric caster according to a second modified example of the present invention.

[0084] Referring to FIGS. 18 to 21, a double eccentric caster (300) according to a second modified example of the present invention comprises a fastening plate (110) fixedly installed on the lower surface of a cart (or unmanned guided vehicle) (10) (see FIG. 1); a caster body (120) rotatably connected to the fastening plate (110); and a moving wheel (130) rotatably installed on the caster body (120).

[0085] When the upper shaft (141) and the lower shaft (141) are inserted and combined into the upper bearing (B1) and the lower bearing (B2), ratchet teeth (180) are formed on the outer surface of the lower shaft (142) and the inner surface of the upper bearing (B1) to prevent them from being separated arbitrarily after combination. Here, ratchet teeth refer to teeth that are inclined only to one side.

[0086] A key groove (191) is formed on the upper surface of the upper bearing (B1) and the upper shaft (141), and on the lower surface of the lower bearing (B2) and the lower shaft (142), and a key (192) is configured to be fastened within the key groove (191).

[0087] In the double eccentric caster (300) according to the second modified example of the present invention configured as described above, when the upper shaft (141) and the lower shaft (141) are inserted and coupled into the upper bearing (B1) and the lower bearing (B2) by the ratchet teeth (180), since the ratchet teeth are structurally designed to only allow forward movement and not backward movement, the coupling of the upper and lower shafts (141, 142) coupled into the upper and lower bearings (B1, B2) is maintained without separation, and furthermore, by fastening the key (192) into the key groove (191), the fastening force can be further improved.

[0088]

[0089] In this way, the present invention has the following effects.

[0090] First, upper and lower bearings are installed on the inner periphery of the fastening plate and the caster body, respectively, to ensure smooth rotation of the double eccentric rotor. Since the double eccentric rotor is configured to rotate around two pivot points, the vertical center line of the upper shaft and the vertical center line of the lower shaft, the turning radius is reduced, and the cart does not deviate from the travel path, and the cart can be prevented from shaking, enabling the safe transport of heavy loads (carrying items).

[0091] Second, it is very convenient to use because the user does not need to use much force to turn the bogie as it rotates around two pivot points.

[0092] Third, in the structure of the double eccentric rotor, bearing support steps are formed at each of the upper and lower ends of the body to support the bearings, thereby stably supporting the load of the weight loaded on the bogie.

[0093]

[0094] Meanwhile, the present specification and drawings disclose preferred embodiments of the present invention. Although specific terms have been used, they are used in a general sense only to easily explain the technical contents of the present invention and to assist in understanding the invention, and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modified examples based on the technical concept of the present invention are possible in addition to the embodiments disclosed herein.

[0095] For example, although the caster of the present invention is described as being applied to a cart, it is possible to apply it to the bottom of a heavy object (product) that requires movement, including furniture, chairs, office equipment, etc., in addition to a cart.

[0096] In addition, the shape of the double eccentric rotor is not limited to the present embodiment, and may be manufactured in other shapes, such as a crankshaft.

[0097] [Explanation of symbols]

[0098] 10: Bogie 100: Double eccentric caster

[0099] 110: Fastening plate 120: Caster body

[0100] 130: Moving wheel 131: Shaft (hinge pin)

[0101] 140: Double eccentric rotor 141: Upper shaft

[0102] 142: Lower shaft B1: Upper bearing

[0103] B2: Lower bearing

Claims

1. A fastening plate (110) fixedly installed on the lower surface of the cart (10); a caster body (120) rotatably connected to the fastening plate (110); and In a caster having a movable wheel (130) that is installed rotatable around a shaft (131) on the caster body (120), A double eccentric rotating body (140) is provided, which comprises an eccentric body (143), an upper shaft (141) formed on the upper side of the eccentric body and installed on the fastening plate (110) with an upper bearing (B1) interposed therebetween, and a lower shaft (142) formed on the lower side of the eccentric body and installed on the caster body (120) with a lower bearing (B2) interposed therebetween. The vertical center line (L1) of the upper shaft (141) and the vertical center line (L2) of the lower shaft (142) are positioned eccentrically so as to rotate at two pivot points. A first insertion hole (110a) is formed in the center of the above-mentioned fastening plate (110) for inserting the upper shaft (141) through the upper bearing (B1), a finishing cap (150) is fastened to the first insertion hole (110a), and a support shaft (160) is installed between the upper shaft (141) and the finishing cap (150) to support the upper end of the upper shaft (141), and the support shaft (160) is installed so as to be rotatably connected to the support bearing (B3). A double eccentric caster characterized in that a support shaft support member (161) having a support mounting groove (160a) is formed protrudingly on the lower surface of the above-mentioned closing cap (150) and the upper surface of the above-mentioned upper shaft (141), and a support bearing support step (160b) for supporting the support bearing (B3) is formed on the bottom surface of the above-mentioned support mounting groove (160a), so that both ends of the above-mentioned support shaft (160) do not come into contact with the bottom surface of the above-mentioned support mounting groove (160a).

2. In paragraph 1, A double eccentric caster characterized in that the upper shaft (141) and the lower shaft (142) have their axes separated from each other.

3. In paragraph 2, A double eccentric caster characterized in that the vertical center line (L1) and the vertical center line (L2) are spaced 20 mm apart, and the vertical center line (L2) and the vertical line (L3) of the shaft (131) of the moving wheel (130) are spaced 10 mm apart.

4. In paragraph 2, A double eccentric caster characterized in that the above double eccentric rotor (140) is configured to reduce the radius of rotation by rotating at two pivot points of the vertical center lines (L1, L2).

5. In paragraph 1, A double eccentric caster characterized in that an upper bearing support step (141a) for supporting the upper bearing (B1) is formed on the upper surface of the eccentric body (143) in contact with the outer surface of the upper shaft (141), and a lower bearing support step (141b) for supporting the lower bearing (B2) is formed on the lower surface of the eccentric body (143) in contact with the outer surface of the lower shaft (142).

6. In paragraph 1, A double eccentric caster characterized in that a lubricant storage space (170) is formed between the closing cap (150) and the fastening plate (110), and a lubricant passage (171) is formed inside the double eccentric rotor (140).

7. In paragraph 1, A double eccentric caster characterized in that when the upper shaft (141) and the lower shaft (142) are inserted into the upper bearing (B1) and the lower bearing (B2) and combined, ratchet teeth (180) are formed on the outer surface of the lower shaft (142) and the inner surface of the upper bearing (B1) to prevent them from being arbitrarily separated after combination.

8. In paragraph 7, A double eccentric caster characterized in that a key groove (191) is formed on the upper surface of the upper bearing (B1) and the upper shaft (141) and the lower surface of the lower bearing (B2) and the lower shaft (142), and a key (192) is fastened within the key groove (191).

Images