JPS646990B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides a door hanger that holds a door removed from a vehicle at a door removal station on a vehicle assembly line and transports the door to a downstream door assembly station. The present invention relates to a door hanger circulation conveyance device for circulation between places, and particularly to improvements in its return system.

(Prior art) Conventionally, in vehicle assembly lines such as automobiles, for reasons such as facilitating the outfitting of the interior of the vehicle, the left and right doors are temporarily removed from the painted vehicle running on the main line at a door removal station, and then the left and right doors are removed at a door removal station. A vehicle assembly system is well known in which a removed door is outfitted on a subline separate from the main line, and then supplied again to a door assembly station on the main line, where it is assembled on a vehicle that has been outfitted on the main line. It is being

In such a vehicle assembly system, a plurality of door hangers that hold doors are normally moved in circulation between a door removal station and a door assembly station, and each door hanger is moved from the door removal station to the door assembly station. The door is transported during the process of moving to. In this case, as a circulating conveyance device for circulating the door hanger, as disclosed in Japanese Patent Application Laid-open No. 53-8884, a conventional method is used to convey the door from the door assembly station to the empty door hanger to the door removal station. It has been proposed that all the door hangers are circulated and transported until they are returned by two independent and dedicated lines, one for the left door and the other for the right door.

(Problem to be Solved by the Invention) However, in this proposal, the door hanger circulation conveyance lines are separated and independent for the left and right doors, respectively, and empty door hangers are simply returned from the door assembly station to the door removal station. Since two lines are required even for a single return process, a large equipment space is required, and the cost increases due to an increase in the line distance and the corresponding increase in the number of door hangers required.

In view of this point, the present invention allows only the empty hanger return line for returning empty door hangers among the door hanger circulation lines between the door removal station and the door assembly station described above to mix the door hangers for the left and right doors, respectively. The main purpose is to reduce equipment space and equipment cost by using one mixed flow line.

By the way, in that case, if the door hangers for the left and right doors are alternately mixed and returned to one empty hanger return line, then the door hangers for the left and right doors will alternately flow into the return line. This increases the amount of time it takes to confirm that the door handles are in place, and the overall return takt time for the four door hangers required to transport the four doors equivalent to one vehicle becomes longer.

Therefore, the present invention further provides a structure in which four empty door hangers corresponding to one vehicle are alternately introduced into the single empty hanger feeding line, two for each of the left and right doors. By doing so, it is possible to partially omit checking of the door hanger flowing into the return line, and the object is to shorten the tact time for returning the door hanger.

(Means for Solving the Problems) In order to achieve these objectives, the configuration of the present invention is as follows:
Between the door removal station and the door assembly station on the vehicle assembly line, there are two door conveyance lines for independently transporting the left and right doors removed from the vehicle at the door removal station to the door assembly station; A circulation line consisting of one empty hanger return line for returning empty door hangers for left and right doors, whose doors have been removed at a door assembly station, to a door removal station is provided.

Further, on the downstream side of the door assembly station of the circulation line, a merging section is provided where the two door conveyance lines merge into one empty hanger return line,
Further, on the upstream side of the door removal station in the circulation line, there is provided a branching section where the one empty hanger return line is branched into two door transport lines.

Furthermore, on the upstream side of the confluence near the confluence,
At the door removal station, two door hangers for the left and right doors are conveyed at intervals corresponding to the distance between the front and rear door installation positions of the vehicle. A control stopper is provided to return the hanger to the return line.

(Function) With the above configuration, in the present invention, the door hangers for the left and right doors circulate through the circulation line, and from the one empty hanger return line to the two empty hanger return lines at the branch section upstream of the door removal station in the vehicle assembly line. It is branched off to a door conveyance line, and further joins an empty hanger return line from the door conveyance line at a convergence point on the downstream side of the door assembly station in the vehicle assembly line. As a result, the door removed from the vehicle at the door removal station is separated into two parts by door hangers for the left and right doors and transported through two door transport lines, and after being outfitted along the way, the door is assembled. The door hanger is assembled to the vehicle at the door assembly station, and the empty door hanger is returned to the door removal station through the empty hanger return line.

In that case, since there is only one return line for returning the empty door hangers, the equipment space is small, and the line length is shortened, reducing the number of door hangers installed, which reduces equipment costs. I can do it.

In addition, at the junction where the two door transport lines join one empty hanger return line, a control stopper placed near the junction upstream of the junction allows the door hangers for the left and right doors to correspond to the vehicle. Then, two empty hangers are alternately returned from two door transport lines to one empty hanger return line. In this way, four door hangers corresponding to one vehicle are divided into left and right doors, and two of them are alternately returned to the empty hanger return line.
The processing time of one cycle for returning a door hanger for a stand is shorter than the return tact time for returning four empty hangers one by one left and right alternately, thereby shortening the return tact time for door hangers. I can do it.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

Figure 1 shows a part of the layout of a vehicle assembly factory for automobiles, etc., and 1 is a vehicle assembly line that transports vehicles W supplied from a painting line in the direction of the arrow in the figure. Stations (not shown) are formed, and the vehicle W is outfitted by assembling various parts to the vehicle W at each outfitting station.

Further, the vehicle assembly line 1 has a door removal station 2 near its upstream end, which removes four left and right doors W ₁ to W ₄ from each vehicle W flowing through the vehicle assembly line 1, and a door removal station 2 near its downstream end. A door assembly station 3 is formed for assembling the four doors W ₁ to W ₄ to each corresponding vehicle W on the vehicle assembly line, and both stations 2, 3
A circulation line 5 is provided between them to circulate and transport four types of door hangers 4a to 4d for holding and transporting the doors _W1 to _W4 , respectively.

The circulation line 5 is connected to the left and right doors removed from each vehicle W at the door removal station 2.
two left and right door conveyance lines 6 that independently convey W ₁ to _{W 4} to the door assembly station 3;
7, and one for returning the empty door hangers 4a to _4d , 4a to _4d , 4a to 4d, . and an empty hanger return line 8. And, on the downstream side of the door assembly station 3 of the circulation line 5,
A junction is provided where the two door transport lines 6 and 7 join one empty hanger return line 8, and on the other hand, upstream of the door removal station 2 of the circulation line 5, the one empty hanger return line 8 is connected to the empty hanger return line 8. line 8 is 2
A dividing section is provided to divide the flow into the book door transport lines 6 and 7.

Then, as shown in the enlarged view in Figure 2, the above 2
Near the junction where the book door transport lines 6 and 7 join one empty hanger return line 8, on the upstream side of the junction, that is, at the downstream end of the left door transport line 6, there is a Door hanger 4a, 4b,
4a, 4b, . A second stopper 10 is provided as a control stopper to restrict the movement of the four door hangers 4a to 4d corresponding to one vehicle W on the empty hanger return line 8. When returning the goods to the station 2, by controlling the operation of the respective stoppers 9 and 10, for example, first the two door hangers 4a and 4b for the left door are returned in succession, and then the two door hangers for the right door are returned. Door hangers 4a, 4b and 4c, 4d for the left and right doors are transported to the vehicle at pitch intervals corresponding to the front and rear door mounting position intervals of the vehicle at the door removal station 2, so that the door hangers 4c, 4d are returned in succession. Then, two empty hangers are alternately returned from two door transport lines 6 and 7 to one empty hanger return line 8.

In addition, in FIG. 1, 11 indicates each door conveyance line 6, 7.
A door conveyance line formed in the middle of each door
W ₁ to _{W 4} are each outfitted with various parts.

Next, the operation of the above embodiment will be explained.
A plurality of pairs of empty door hangers 4a to 4d, 4 are returned to the vicinity of the door removal station 2 along the empty hanger return line 8 in the circulation line 5.
a to 4d, ...... are respectively the station 2
Just before entering the door removal station 2 at the upstream branch, hangers 4a, 4b, 4a, 4 for the left door are installed.
b, ...... and hangers 4c, 4d, 4 for the right door
It is separated into c, 4d, ...... Then, the left door hangers 4a, 4b, 4a, 4b, . ,4d,4c,4
d, ...... hold the front and rear right doors at the door removal station 2, and then pass through the door conveyance line 7 to the door assembly station 3, respectively.
transported to. Through this process, the four left and right doors W ₁ to W ₄ removed from each vehicle W at the door removal station 2 are held by the door hangers 4a, 4b, 4c, and 4d for the left and right doors, respectively. The door is moved from the door removal station 2 to the door outfitting line 11, where it is outfitted in a predetermined manner, and then transported to the door assembly station 3 and assembled into the corresponding vehicle W on the vehicle assembly line 1.

Then, install the door at door assembly station 3 above.
Empty door hangers 4a to 4 with W ₁ to W ₄ installed
After passing through the door assembly station 3, the stoppers 9 and 10 actuate the door hangers 4a, 4b and 4c, 4d for the left and right doors, respectively. At the confluence point, it flows into the empty hanger return line 8,
It is returned to the door removal station 2 through the return line 8 and used for the next door transport.

Therefore, since there is only one return line 8 for returning the empty door hangers 4a to 4d, 4a to 4d, . . ., the equipment space is small and the line length is shortened. Since the number of installed door hangers 4a to 4d is also reduced, equipment costs can be reduced.

In addition, multiple sets of empty door hangers 4a to 4
Considering the return tact time of d, 4a to 4d, . . ., for example, in FIG. A position X, which is separated by a distance, is set as a confirmation position to confirm the passage of each hanger 4a to 4d, and this confirmation position _, the distances from _this confirmation position Let the pitch of the conveyor pusher be α. Pitch α of this conveyor pusher
is the transport pitch interval of the door hangers 4a to 4d corresponding to the front and rear door mounting positions of one vehicle W. Then, install four door hangers 4a to 4d corresponding to one vehicle W, one for the left and right doors.
When the door hangers 4a to 4d are returned one by one in turn, one cycle of processing time T ₁ required to complete the return of the four door hangers 4a to 4d is T ₁ = 2× {(l ₁ /V) + (l ₂ /V) } becomes. On the other hand, in the case of the embodiment of the present invention in which two units for the left and right doors are returned alternately, the processing time T ₂ for one cycle is T ₂ =l ₁ /V+l ₂ /V+2×α/V, and α Since <l ₁ and α<l ₂ , T ₂ <T ₁ . In this case, it is confirmed at confirmation position X that the second of the door hangers 4a to 4d, which are returned alternately two by two, has passed, and the stoppers 9 and 10 are activated.
That is, door hangers 4a to 4d, 4a to 4d,
The return tact time for alternately returning two units at a time is shorter than the return tact time for alternately returning one unit at a time, so the door hangers 4a to 4d, 4
It is possible to shorten the return tact time of a to 4d, . . . .

(Effects of the Invention) As explained above, according to the present invention, the left and right doors removed from the vehicle at the door removal station on the vehicle assembly line are transported downstream of the vehicle assembly line by two independent and dedicated door conveyance lines. The empty door hangers are transported to the side door assembly station, and the empty door hangers with the doors unloaded at the door assembly station are returned to the empty hanger return line, two for each of the left and right doors, by a controlled stopper. Since the empty door hanger is returned to the door removal station via the empty door hanger return line, only one empty door hanger return line is required, reducing equipment space and equipment cost. . In addition, since two empty door hangers for the left and right doors are returned alternately, the return tact time can be reduced compared to the case where empty door hangers for the left and right doors are returned one at a time. In addition to contributing to the improvement of equipment capacity, one set of four door hangers for one vehicle can be supplied to the door removal station in a short time.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall schematic explanatory view, and FIG. 2 is an enlarged explanatory view of the part where the downstream end of the door conveyance line joins the upstream end of the empty hanger return line. 1...Vehicle assembly line, 2...Door removal station, 3...Door assembly station, 4a
~4d...Door hanger, 5...Circulation line, 6...
...Left door transport line, 7...Right door transport line,
8...Empty hanger return line, 9,10...Stopper, W...Vehicle, _W1 to _W4 ...Door.

Claims (1)

[Scope of Claims] 1. Two doors are provided between the door removal station and the door assembly station on the vehicle assembly line, each independently transporting the left and right doors removed from the vehicle at the door removal station to the door assembly station. A circulation line is provided, consisting of a door conveyance line, and an empty hanger return line for returning empty left and right door door hangers whose doors have been unloaded at the door assembly station to the door removal station. On the downstream side of the door assembly station, there is provided a merging section where the two door transport lines join into one empty hanger return line, and on the upstream side of the door removal station of the circulation line, A diversion section is provided where the empty hanger return line is divided into two door conveyance lines, and on the upstream side of the merging section near the above-mentioned merging section, there are pipes arranged at pitch intervals corresponding to the distance between the front and rear door installation positions of the vehicle at the door removal station. The present invention is characterized in that a control stopper is provided for alternately returning two door hangers for left and right doors that are being transported, corresponding to each vehicle, from two door transport lines to one empty hanger return line. Door hanger circulation conveyance device.