This application claims the benefit of Korean Application No. 2006-120349, filed Dec. 1, 2006, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an apparatus for conveying an article on a plurality of rotatable parallel shafts, and more particularly, to an apparatus for conveying an article on a plurality of rotatable parallel shafts with a decreased possibility of deflection of the shafts.
2. Description of the Related Art
Articles can be conveyed on a plurality of parallel shafts arranged in series. Conveyors with a series of parallel shafts are widely used in various fields such as manufacturing and logistics fields.
In such a conveyor, shafts can be deflected by their own weight or an article placed thereon. Particularly, a long shaft can be easily deflected. In this case, articles cannot be smoothly conveyed, and the lifespan of the conveyor can be shortened. Particularly, when the conveyor carries an article that can be easily damaged by deflection such as a flat display panel and a wide glass plate, deflection of the shafts may results in serious problems.
In addition, ball bearings supporting the shafts can be easily contaminated and damaged by abrasion when the shafts are deflected.
To address these problems, several methods have been proposed, such as a method of increasing the diameter of shafts and a method of filling a predetermined material into shafts. However, such methods increase the size and manufacturing costs of a conveyor and complicate the structure of the conveyor.
Accordingly, the present invention is directed to a conveying apparatus that substantially obviates one or more problems due to limitations and disadvantages of the related art.
Embodiments of the present invention provide a conveying apparatus having a structure for preventing deflection of shaft.
Embodiments of the present invention also provide a conveying apparatus including shafts that can be adjusted in tension according to the allowable deflection of an article to be conveyed.
Additional advantages and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
In one aspect of the present invention, there is provided an apparatus for conveying, the apparatus includes a plurality of parallel main shafts. A plurality of auxiliary shafts is inserted through the main shafts, respectively, so as to prevent deflection or bending of the main shafts.
The auxiliary shafts are inserted through the main shafts and have both ends fixed to a frame, and a plurality of bearing members is disposed between the main shafts and the auxiliary shafts for supporting the main shafts and allowing rotation of the main shafts. Furthermore, a tension unit is disposed at both ends or one end of the auxiliary shaft for adjusting tension of the auxiliary shaft.
Each of the bearing members may include a ball bearing coupled to the auxiliary shaft by insertion. Each of the bearing members may further include a bearing fixing member for preventing movement of the ball bearing.
In some embodiments, the apparatus may further include a frame support member. The frame support member may be disposed in parallel to the main shafts to support the frame so as to prevent bending of the frame when the auxiliary shaft is pulled by the tension unit.
In other embodiments, the apparatus may further include a reinforcement shaft having a diameter greater than that of the auxiliary shaft and axially connected to the auxiliary shaft. In this case, the tension unit may be disposed at an end of the reinforcement shaft.
The tension unit may include a bolt unit formed at an end of the auxiliary shaft, and a nut unit coupled to the bolt unit for pulling the auxiliary shaft. In this case, the tension of the auxiliary shaft can be adjusted using the nut unit.
The apparatus may further include a roller rotatably coupled to the main shaft by insertion.
The apparatus may further include a motor, a rotation shaft, and a power transmission unit for rotating the main shafts.
The rotation shaft is disposed perpendicular to the main shafts and rotatable by receiving rotation power from the motor. The power transmission unit transmits rotation power from the rotation shaft to the main shafts.
For example, non-contact gears formed by first and second magnets can be used as the power transmission unit. The first magnets are disposed at ends of the main shafts, respectively. The second magnet is mounded on the rotation shaft by insertion to apply a repulsive force to the first magnets when rotating with the rotation shaft so as to transmit rotation power from the rotation shaft to the first magnets.
In another aspect of the present invention, there is provided an apparatus for conveying. Instead of the above-mentioned bearing member, the apparatus can include a main magnet unit formed on an inner surface of the main shaft, and an auxiliary magnet unit formed on an outer surface of the auxiliary shaft for supporting the main shaft by applying a repulsive force to the main magnet unit.
In a further another aspect of the present invention, there is provided an apparatus for conveying. Instead of the above-mentioned bearing member, an auxiliary shaft of the apparatus can be shaped like a closed cylinder having a cavity portion. Air (usually, compressed air) can be injected into the cavity portion. Then, the air can be discharged from the cavity portion through a plurality of discharge holes for supporting the main shaft using the discharged air.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
Referring to
In the current embodiment, the motor 103 is used as an actuator for rotating the main shafts 101. However, for example, the main shafts 101 can be rotated by a force directly applied to an article placed on the main shafts 101. In other words, the motor 103, the rotation shaft 105, and the power transmission unit 107 may not be included in the conveying apparatus 100.
The main shafts 101 have a pipe shape. The material and thickness of the main shafts 101 can be varied according to articles to be conveyed. For example, when a glass plate for a flat display device is conveyed on the main shafts 101, the main shafts 101 can be formed of a light material such as aluminum (Al) and have a diameter of about 10 mm and a thickness of about 2 mm. Alternatively, the main shafts 101 can be formed of other materials such as stainless steel and a polymer.
The main shafts 101 are supported by auxiliary shafts 109 and bearing members 115. Thus, an external structure is not necessary for supporting the main shafts 101. The auxiliary shafts 109 disposed through the main shafts 101 for preventing the main shafts 101 from deflecting and bending.
The auxiliary shafts 109 pass through the main shafts 101 and are fixed to a frame 111. Tension units 113 are attached to right ends and/or left ends of the auxiliary shafts 109 to apply a tension force to the auxiliary shafts 109 so that the auxiliary shafts 109 can stably support the main shafts 101. The auxiliary shafts 109 may be formed of a material suitable for bearing a tension force from the tension units 113. For example, the auxiliary shafts 109 can be formed of stainless steel or carbon steel.
The tension of the auxiliary shafts 109 can be maintained at a desired level owing to the tension units 113. Therefore, for example, the auxiliary shafts 109 can easily absorb a vertical impact force. In addition, even when the auxiliary shafts 109 are deformed by an impact force, the auxiliary shafts 109 can easily return to their original shapes. The auxiliary shafts 109 have an outer diameter smaller than the inner diameter of the main shafts 101 so as not to hinder the rotation of the main shafts 101.
The allowable deflection or bending of the main shafts 101 or the auxiliary shafts 109 can be varied according to articles to be conveyed. For example, when a glass plate is conveyed on the conveying apparatus 100, the allowable deflection of the main shafts 101 may be low (e.g., 0.5 mm or lower) since the glass plate can be easily damaged or broken by deflection. However, for example, when a robust article is conveyed on the conveying apparatus 100, the allowable deflection of the main shafts 101 can be increased. Therefore, in the current embodiment, the tension unit 113 can finely adjust the tension of the auxiliary shaft 109, thereby finely controlling the deflection of the main shaft 101.
The main shafts 101 are also supported by the bearing members 115 disposed on the auxiliary shafts 109. Therefore, additional bearing members for enclosing and supporting both ends of the main shafts 101 may not be necessary.
The bearing members 115 are disposed between the main shafts 101 and the auxiliary shafts 109 for supporting the main shafts 101 and allowing rotation of the main shafts 101. The bearing members 115 can be fixed to the auxiliary shafts 109 for supporting the main shafts 101. The main shafts 101 supported by the bearing members 115 can be rotated by rotation power transmitted through the power transmission unit 107.
In a conventional conveyor, shafts are supported at two points (e.g., both ends of the shafts). However, in the current embodiment of the present invention, the main shafts 101 are supported at multi points using the auxiliary shafts 109 and the bearing members 115. Owing to this structure, a vertical force applied to the main shafts 101 can be easily distributed and absorbed. Therefore, the main shafts 101 can be formed of a much lighter material, and the bearing members 115 can have a small size. As a result, the structure of the conveying apparatus 100 can be simple.
Referring to
Referring to
Referring to
Referring to
A plurality of roller units 501 is disposed at each of the main shafts 101 for supporting an article to be conveyed. The roller units 501 have predetermined elasticity so that an impact force applied to the roller units 501 by an article or due to other reasons can be absorbed.
In addition, when the auxiliary shafts 109 fixed to the frame 111 are pulled using the tension units 113, the frame 111 can be bent in an axial direction of the main shafts 101. For this reason, a frame support member 503 can be disposed between bars of the frame 111. Furthermore, the frame 111 can have an extension in the axial direction of the main shafts 101 (for example, the frame 111 can be L- or ⊂-shaped).
Referring to
The conveying apparatus 500 includes a bearing member 115 disposed between the auxiliary shaft 109 and the main shaft 101 for supporting the main shaft 101, and spring clips 703 and 705. In the current embodiment, a bearing with rolling contact, such as a ball bearing 701, is used as the bearing member 115. The spring clips 703 and 705 are used to fix the ball bearing 701. The ball bearing 701 is mounted on the auxiliary shaft 109, and the spring clips 703 and 705 are disposed at both sides of the ball bearing 701 to firmly fix the ball bearing 701.
The roller unit 501 is coupled to the main shaft 101 by insertion. The roller unit 501 includes a roller 707 and bushings 709 and 711 for fixing the roller 707 to the main shaft 101. The roller 707 has proper elasticity. Therefore, when an article is conveyed on the conveying apparatus 500, an impact force applied to the roller 707 by the article can be effectively absorbed.
A rotation shaft 105 is disposed perpendicular to the main shaft 101. The rotation shaft 105 transmits power from the motor 103 to the power transmission unit 107. Here, a gear train can be used for the power transmission between the motor 103 and the rotation shaft 105. In
Referring to
In the first magnet unit 701, a magnet 901 is fixed using bushings 903 and 905 and is hooked on the main shaft 101 using a collet 907. A tubular spacer 909 is fitted between the first magnet unit 701 and the frame 111. The first magnet unit 701 is supported by a bearing member such as a ball bearing 911 disposed between the main shaft 101 and the auxiliary shaft 109.
The first and second magnet units 701 and 703 can be considered non-contact gears. When the second magnet unit 703 rotates, the first magnet unit 701 also rotates due to a repulsive force between the first and second magnetic units 701 and 703. Therefore, when the second magnet unit 703 rotates with the rotation shaft 105, the main shaft 101 also rotates owing to the first magnet unit 701 fixed to the main shaft 101.
Since the first and second magnetic units 701 and 703 do not make contact with each other (i.e., the first and second magnetic units 701 and 703 are spaced a predetermined distance), noises, irregular motions, and generation of undesired particles can be prevented.
The tension unit 113 includes a bolt unit 913 and a nut unit 915. The bolt unit 913 is disposed at an end of the auxiliary shaft 109, and the nut unit 915 is coupled to the bolt unit 913. The auxiliary shaft 109 can be fixed to the frame 111 by fastening the nut unit 915, and the tension of the auxiliary shaft 109 can be adjusted by fastening or releasing the nut unit 915. Alternatively, a turn buckle can be used as the tension unit 113.
An end of the main shaft 101 opposite to the power transmission unit 107 is fixed together with a ball bearing 119 using an end cap 117, and a ring stopper 123 is fixed to the auxiliary shaft 109 using a set screw 121. Therefore, the main shaft 101 can be firmly fixed without an axial motion.
The tension unit 113 can be disposed on an end of the auxiliary shaft 109 opposite to the power transmission unit 107.
For example, if it is difficult to form a bolt unit at the auxiliary shaft 109 since the auxiliary shaft 109 has a small diameter, a reinforcement shaft 109-a having a diameter greater than that of the auxiliary shaft 109 can be used. In this case, a nut formed at one end of the reinforcement shaft 109-a can be coupled to a bolt formed at an end of the auxiliary shaft 109 for axial connection between the reinforcement shaft 109-a and the auxiliary shaft 109. A bolt unit 913-a of the tension unit 113 can be formed at the reinforcement shaft 109-a.
In the bearing member of
In the bearing member of
As described above, according to the present invention, the conveying apparatus includes the auxiliary shaft as well as the main shaft. Therefore, the main shaft can be prevented from deflection or bending caused by its own weight or an article placed thereon. Furthermore, the main shaft is supported at multi points so that a force applied to the main shaft from an upper side can be easily distributed and dampened. In this case, the main shaft can be formed of a light material, and the bearing member supporting the main shaft can have a small size. Accordingly, the conveying apparatus can have a simple structure.
In addition, the auxiliary shaft used to support the main shaft can be precisely adjusted in tension by using the tension unit. Therefore, a supporting force applied to an article from the auxiliary shaft (or the main shaft) can be precisely adjusted by adjusting the tension of the auxiliary shaft using the tension unit.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
Number | Date | Country | Kind |
---|---|---|---|
2006-120349 | Dec 2006 | KR | national |