Abstract:
An apparatus for changing a position of and carrying a wheel has a structure such that manipulation for changing the position of the wheel from a horizontal state into a vertical state in a wheel mounting process in a vehicle assembly line is simplified and a process of carrying the wheel to a subsequent process can be easily conducted. Embodiments of the apparatus include an advancing conveyor, a position-changing device, and a carrying device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present application is based on, and claims priority from, Korean Application Serial Number 10-2005-0121453, filed on Dec. 12, 2005, the disclosure of which is hereby incorporated by reference herein in its entirety.  
       FIELD OF THE INVENTION  
       [0002]     The present invention relates to apparatuses for changing positions of and carrying wheels and, more particularly, to an apparatus used in a vehicle assembly line for automatically changing the position of a wheel from a horizontal state to a vertical state, and for carrying the wheel to a mounting process.  
       BACKGROUND OF THE INVENTION  
       [0003]     Generally, when an object is automatically carried by a carrying device such as a conveyor, it may be necessary to change the direction in which the object is moved or to change the position of the object by an angle of 90°, that is, from a horizontal state to a vertical state or from a vertical state to a horizontal state.  
         [0004]     To achieve the above purpose, an apparatus for changing a position of a wheel was proposed in Japan Utility Model Laid-open Publication No. Heisei. 6-54638. In this wheel position-changing apparatus, an L-shaped bucket, which supports a wheel supplied to the wheel position-changing apparatus, is provided to be rotatable from a vertical state to a horizontal state by a bucket-actuating cylinder. At least one flap is provided at a predetermined position on the bottom of the bucket. The flap is rotated between the bottom and an upright position by a flap actuating cylinder. Thus, while the flap is folded into the bottom of the bucket, the wheel is rolled and placed in the bottom of the bucket. The wheel is brought into contact with a stopper. Then, the flap is rotated to the upright position by the flap actuating cylinder, thus preventing the wheel from rolling. Thereafter, the bucket is rotated by the bucket actuating cylinder, thereby changing the position of the wheel from a vertical state to a horizontal state.  
         [0005]     However, in the conventional wheel position-changing apparatus, in the process of placing the wheel in the bottom of the bucket, because a worker must place the wheel in the bucket using his/her hands, it is very inconvenient, and workability is reduced. Furthermore, the conventional wheel position-changing apparatus cannot be directly used in a vehicle assembly line, in which wheels are supplied to a wheel mounting process. To use the conventional wheel position-changing apparatus in the vehicle assembly line, a separate vertical position-changing device and carrying device are required. Therefore, expenses increase and relatively large space is required to install the apparatus.  
       SUMMARY OF THE INVENTION  
       [0006]     Embodiments of the present invention provide apparatus for changing the position of and carrying a wheel, which has a structure such that manipulation of changing the position of the wheel from a horizontal state to a vertical state in a wheel mounting process in a vehicle assembly line is simplified and a process of carrying the wheel to a subsequent process is easily conducted.  
         [0007]     An apparatus for changing a position of and carrying a wheel according to an exemplary embodiment of the present invention includes an advancing conveyor. The advancing conveyor has a frame. Roller support bars are provided on an upper end of the frame at positions spaced apart from each other by a predetermined distance. A plurality of carrying rollers is horizontally provided between the roller support bars and operated in conjunction with each other by a motor. A plurality of guide rollers is vertically provided on the roller support bar that is disposed at an outermost position. A position-changing device has a base plate, which is provided on a side surface of the frame. A support shaft is provided on the base plate. A support plate is coupled to the support shaft through a bracket. At least two rotating bars are mounted to the support plate such that the rotating bars are placed between the carrying rollers. A plurality of tread support rollers is provided on the support plate such that the tread support rollers are supported by the roller support bar, which is disposed at an inner position. The tread support rollers are perpendicular to the two rotating bars. A link is coupled to the support shaft. A position-changing cylinder is installed in the frame and coupled to the link so that the tread support rollers and the two rotating bars are rotated at an angle of 90° by the position-changing cylinder. A carrying means has a plurality of wheel side support rollers, which are vertically provided on the base plate around an outer edge of the base plate. A pusher is provided on a support pole placed ahead of the base plate. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]     For a better understanding of the nature and objects of the present invention, reference should be made to the following detailed description with the accompanying drawings, in which:  
         [0009]      FIG. 1  is a perspective view of an apparatus for changing a position of and carrying a wheel, according to an embodiment of the present invention;  
         [0010]      FIG. 2  is a plan view of the apparatus of  FIG. 1 ;  
         [0011]      FIG. 3  is a side view of the apparatus of  FIG. 1 ; and  
         [0012]      FIG. 4  is a view showing the operation of a position-changing device of the apparatus of  FIG. 1 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0013]     Hereinafter, an exemplary embodiment of the present invention will be described in detail with reference to the attached drawings.  
         [0014]     In the drawings, the reference numeral  10  denotes an advancing conveyor. In the advancing conveyor  10 , roller support bars  12   a  and  12   b  are provided on an upper end of a rectangular frame  11  at positions spaced apart from each other by a predetermined distance, and a plurality of carrying rollers  13  is provided between the roller support bars  12   a  and  12   b . Furthermore, a sprocket  14  is provided on an end of each carrying roller  13 . A geared motor  15  is mounted to the frame  11  at a position adjacent to the roller support bar  12   a , and a sprocket  16  is provided on the carrying roller  13 , which is disposed just above the geared motor  15 . The sprockets  14 , the geared motor  15  and the sprocket  16  are coupled to each other using chains such that they are operated in conjunction with each other. A support member  18  is provided on the roller support bar  12   a , and a plurality of guide rollers  19  is installed in the support member  18 .  
         [0015]     Furthermore, a stop plate  20  is vertically provided behind a downstream end of the carrying rollers  13  in the frame  11 . An approach or contact sensor  21  is provided on the stop plate  20 , so that when a wheel, which has been carried by the carrying rollers  13  in a horizontal position, is brought into contact with the stop plate  20 , an output signal of the sensor  21  controls the geared motor  15 .  
         [0016]     In the drawings, the reference numeral  30  denotes a position-changing device. In the position-changing device  30 , a frame  31  is mounted to the surface of the frame  11 , and a base plate  32  is placed on the upper surface of the frame  31 . A support shaft  33  is supported at opposite ends thereof on the base plate  32  through bearings  34   a  and  34   b . A support plate  36  is coupled to the support shaft  33  through brackets  35   a  and  35   b . At least two rotating bars  37   a  and  37   b  are perpendicularly coupled to the support plate  36  between the carrying rollers  13  such that upper surfaces of the rotating bars  37   a  and  37   b  are below upper surfaces of the carrying rollers  13 . Furthermore, a support member  38  is provided on the support plate  36 . A plurality of tread support rollers  39  is provided in the support member  38  in a direction perpendicular to the rotating bars  37   a  and  37   b , so that when the rotating bars  37   a  and  37   b  are horizontal, the tread support rollers  39  face the guide rollers  19  and are at the same height as the guide rollers  19 . In addition, the tread support rollers  39  serve to support the tread of the wheel.  
         [0017]     Furthermore, a link  40  is securely coupled to the support shaft  33  and is coupled to an actuating rod  42  of a position-changing cylinder  41 , which is installed in the frame  11 . An approach or contact sensor  43 , a shock absorber  44  and a sag prevention stopper  45  are provided on the base plate  32  at a predetermined position corresponding to the position of the support plate  36  when it is rotated in a horizontal direction. Therefore, when a wheel is detected by the sensor  21 , which is provided in the stop plate  20 , the geared motor  15  is stopped by an output signal of the sensor  21  and, simultaneously, the position-changing cylinder  41  of the position-changing device  30  is operated. Thus, the rotating bars  37   a  and  37   b  are stood upright, while the tread support rollers  39  are oriented in horizontal directions. Then, the wheel, which has been in a horizontal state, enters a state of standing vertically. Furthermore, when the support plate  36  and the tread support rollers  39  are converted to horizontal states, the support plate  36  approaches or contacts the sensor  43 . At this time, the position-changing cylinder  41  is stopped by an output signal of the sensor  43 , and the wheel maintains the state of standing upright.  
         [0018]     In the drawings, the reference numeral  50  denotes a carrying means. The carrying means  50  includes support members  52   a  and  52   b , which are provided at upper and lower positions on support rods  51   a  and  51   b  which are provided on the surface of the base plate  32 , and a plurality of wheel side support rollers  53   a  and  53   b , which are respectively installed in the support members  52   a  and  52   b  in vertical directions. Preferably, heights of the wheel side support rollers  53   a  and  53   b  can be adjusted by a structure in which slots are formed in the support rods  51   a  and  51   b  or in the support members  52   a  and  52   b  and the support members  52   a  and  52   b  are movably coupled to the support rods  51   a  and  51   b  using bolts fitted into the slots. As such, thanks to the structure by which the heights of the wheel side support rollers  53   a  and  53   b  can be adjusted, the present invention can carry wheels having various diameters without damaging rims of the wheels.  
         [0019]     Meanwhile, support rods  54   a  and  54   b  are provided ahead of an upstream end of the base plate  32 , and a support plate  55  is provided at an upper position on the support rods  54   a  and  54   b . A pusher  56  is mounted to the support plate  55 . The pusher  56  includes a pneumatic cylinder  57 , a pushing plate  59 , which is coupled to an actuating rod  58  of the pneumatic cylinder  57 , and a plurality of rollers  60 , which are provided on the pushing plate  59 . The pusher  56  is controlled by the sensor  43 . Furthermore, actuating rod position detecting switches  61   a  and  61   b , which control the stroke of the actuating rod  58 , are provided in the pneumatic cylinder  57 .  
         [0020]     When the rollers  60  push the wheel, the rollers  60  are in rolling contact with the tire of the wheel, so that the pushing operation can be conducted more smoothly.  
         [0021]     In the drawings, the reference numeral  22  denotes a sag prevention stopper.  
         [0022]     When a wheel enters the advancing conveyor  10  in the state in which the rotating bars  37   a  and  37   b  are horizontal, the tread support rollers  39  are vertical, and the pusher  56  is in a retracted state, the wheel is carried on the carrying rollers  13  by the operation of the motor  15  in a horizontal state under the guide of the guide rollers  19  and the tread support rollers  39 . When the wheel is moved to the stop plate  20 , the sensor  21 , which is provided on the stop plate  20 , detects the wheel and stops the motor  15  using an output signal thereof. Simultaneously, the actuating rod  42  of the position-changing cylinder  41  is retracted backwards. Then, the rotating bars  37   a  and  37   b  are rotated and stood upright, and the tread support rollers  39  are rotated and oriented in a horizontal direction. As such, when the position-changing device  30  conducts the position-changing process, the shock absorber  44  serves to prevent noise, and the sag prevention stopper  22  prevents the wheel from excessively rotating. Furthermore, when the support plate  36 , in which the tread support rollers  39  are installed, is oriented in a horizontal direction, the sensor  43  detects this and stops the position-changing cylinder  41  using an output signal thereof. The wheel remains in the vertical state (see,  FIG. 4 ).  
         [0023]     As well, when the wheel is changed into the vertical state, the actuating rod  58  of the pusher  56  is advanced by the output signal of the sensor  43  to carry the wheel towards a subsequent conveyor. After a process of carrying the wheel has been completed, the pusher  56  is retracted backwards and then the position-changing cylinder  41  is advanced by the sequence control of a programmable logic controller (PLC). Then, the tread support rollers  39  enter the vertical state, and the rotating bars  37   a  and  37   b  are returned to the horizontal state, thus preparing for the conveyance of a subsequent wheel.  
         [0024]     As such, the position-changing device  30  is provided around a downstream end of the advancing conveyor  10 , that is, a wheel is automatically carried to the position-changing device  30  at the downstream end of the advancing conveyor  10 . Therefore, a process of carrying the wheel to the position-changing device  30  is simplified, thus workability thereof is enhanced. Furthermore, the pusher  56  is provided ahead of an upstream end of the position-changing device  30 , so that the wheel can be moved to the subsequent conveyor just after the position of the wheel is changed. Accordingly, the structure of the apparatus is simplified, and the space required to install the apparatus is reduced.  
         [0025]     As is apparent from the foregoing, in an apparatus for changing the position of and carrying a wheel according to the present invention, a position-changing device is provided around the downstream end of an advancing conveyor, and a pusher is provided ahead of the upstream end of the position-changing device, so that an operation of changing the position of the wheel, which has been carried in a horizontal state, to a vertical state is simplified, thus workability thereof is enhanced. Furthermore, the wheel can be moved to a subsequent conveyor just after the position of the wheel is changed. Accordingly, the structure of the apparatus is simplified, and the space required to install the apparatus is reduced, thus expense is reduced.