JPH0366070B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a welding jig exchange device mainly used in a welding line for car body assembly.

(Conventional technology) Conventionally, as a welding line for car body assembly, the
As seen in Japanese Patent No. 59-114173, a set station is arranged behind the welding station, and a payout station is arranged in front of the welding station, and a set cart that can freely move back and forth between the set station and the welding station is provided. A pay-out cart is provided between the welding station and the pay-out station so as to be movable back and forth, and the floor, roof, and side panels, which are vehicle body components, are set on the set cart at the set station, and these are placed on the set cart. The welded car body is transported to a welding station and welded by automatic welding equipment placed on both sides of the welding station, and the welded car body is transported by the delivery cart to the delivery station, and from the delivery station to the additional welding line using a hanger or the like. Those who decided to take it out are known.

In addition, in order to replace the welding jig provided in automatic welding equipment, as seen in Japanese Patent Publication No. 12114/1983,
A replacement trolley capable of mounting a welding jig is prepared, and shunting rails are provided on both sides of the set station that are connected to the running rails of the setting trolley via a switch, and the replacement trolley is moved from the switching rails to the running rails. It is also known to transport jigs to a welding station via a In models that set panels, side panel setting devices are placed on both sides of the setting station, so switching rails cannot be placed on both sides of the setting station.In this case, changing rails are installed on both sides of the dispensing station. It is conceivable to provide exchange rails on both sides of the running rails of the unloading carriage, and to carry the exchange carriage into the welding station from the unloading station side via the running rails of the unloading carriage.

(Problem to be Solved by the Invention) By the way, when exchanging jigs is performed by providing exchanging rails on both sides of the dispensing station as described above, one exchanging rail is equipped with an empty exchanging trolley and the next one is used. The exchange cart loaded with the welding jig and the next payout to be used are placed on standby, and after sending the payout cart to the shunting rail on the other side, the empty changing cart is loaded into the payout station from the shunting rail on one side. Then, the exchange cart is transported along the running rail to the welding station by the drive mechanism for the delivery cart, and after transferring the used welding jig to the exchange cart, it is returned to the delivery station and transferred to the other side. The replacement cart loaded with the welding jig to be used next is then fed into the shunting station from the shunting rail on one side, transported to the welding station along the traveling rail, and transferred to the automatic welding equipment. The welding jig on the exchange trolley is transferred, the empty exchange trolley is sent from the dispensing station to the shunting rail on the other side, and then the dispensing to be used next is fed into the dispensing station from the shunting rail on one side. and complete the replacement work.

The above is a case where a dedicated payout cart is provided for each model, but since this increases equipment costs, it may be possible to replace only the arc receiver attached to the cart without replacing the payout cart itself.

However, in this case, the dispensing cart that was sent out first to the shunting rail on the other side must be placed in the dispensing station in reverse order with the exchange cart that will be sent out to the shunting rail afterwards, and the shunting It becomes necessary to connect a retractable rail or the like to the rail, which complicates the structure, and it also takes time to replace the rail, resulting in a problem of reduced work efficiency.

In addition, in order to solve this problem and to secure a wide working space on both sides of the unloading station for transferring the workpieces to hangers, etc., the distance between the welding station and the unloading station is increased, and the workpieces are A shunting station is provided in the middle of a conveyance path connecting both stations, and shunting rails are provided on both sides of the shunting station, and only the shunting trolley is delivered from the shunting rail to the shunting station with the unloading cart waiting at the unloading station. It is also possible to configure the welding station so that the welding station and the unloading station can be inserted into the welding station, but in this case, the distance between the welding station and the unloading station becomes long, and it takes time for the unloading cart to travel back and forth between the two stations, which increases the cycle time. There is a problem that productivity decreases due to an increase in

An object of the present invention is to provide a device that solves these problems.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a welding station and a dispensing station in front of the welding station,
A welding line in which workpieces are welded by an automatic welding device having welding jigs placed on both sides of the welding station, and the welded workpieces are transported from the welding station to the delivery station via a transport path extending forward. The welding jig of the automatic welding device is exchanged by transporting an exchange cart capable of carrying a welding jig into the welding station via the conveyance path, wherein a transfer bar is provided on the conveyance path. The reciprocating movement of the transfer bar causes the workpiece to be sequentially sent from the welding station to the unloading station via an intermediate station provided at the center of the transport path, and an exchange cart is provided in the middle of the transport path. A station is provided, and running rails for the exchange trolley extending from the welding station to the shunting station are provided on both sides of the transfer path where the transfer bar is arranged, and switches are provided on the traveling rails on both sides of the shunting station. a shunting rail for a replacement trolley connected through the shunting rail, and an engaging member that engages with the replacement trolley loaded from the shunting rail to the shunting station, the transfer bar being provided with an engaging member that engages with the switching trolley, which controls the movement of the transfer bar. The exchange cart is characterized in that it can freely reciprocate between the exchange station and the welding station.

(Function) When the transfer bar reciprocates forward, the work in the welding station is supported by the rear end of the bar and sent to the intermediate station, and the work in the intermediate station is supported by the front end of the bar and sent to the payout station. The reciprocating stroke of the transfer bar is only half the workpiece transport distance from the welding station to the unloading station, and the distance between the two stations is long because an exchange station is provided in the middle of the transport path that connects the two stations. Workpieces can be transported efficiently even when the workpiece is worn out.

When replacing a welding jig, in advance, expect an empty exchange cart on the shunting rail on the side of the shunting station, and a replacement with the welding jig to be used next on the shunting rail on the other side. First, an empty exchange trolley is put into the exchange station from one side of the exchange rail, and the engaging member of the transfer bar is engaged with it, and in this state, the bar is returned backward toward the welding station. After moving the exchange cart to the welding station and transferring the used welding jigs from the automatic welding devices on both sides to the exchange cart, move the bar forward to move the exchange cart. Return to the shunting station.

Next, the exchange trolley is sent from the shunting station to the shunting rail on one side, and the exchange trolley on the shunting rail on the other side is put into the shunting station, and the exchange trolley is transferred in the same manner as above. Carrying it into the welding station by the backward movement of the bar, transferring the welding jig on the exchange cart to the automatic welding device, then returning the empty exchange cart to the exchange station by the forward movement of the bar, Send it to the other side of the shunting rail to complete the replacement work.

(Example) Referring to FIGS. 1 and 2, A indicates a welding station, B indicates a delivery station in front of the welding station, and on both sides of the welding station A, as shown in FIG. An automatic welding device 2 equipped with a welding jig 1 equipped with various welding guns 1a for welding a floor panel Wa, a roof panel Wb, and a side panel Wc is arranged, and the welding station A
The automobile body W welded together is transported from the station A to the delivery station B via the transport path 3 extending forward, and from the delivery station B, the car body W is transferred to the next process's multi-stroke welding line using a hanger or the like. I decided to move it out.

The welding jig 1 is a machine base 2a of the automatic welding device 2.
The welding jig 1 is removably attached to the inner surface of a pedestal 2b provided above that is movable laterally, and a welding jig 1 is protruded from the welding station A, as shown in FIGS. 4 and 5. The gripping member 4a gripped by the docking member 1b is attached to the automatic welding device 2 on both sides,
An exchange trolley 4 having two sets of support frames 4b attached on the left and right in correspondence with the welding apparatus 2 was carried in, and the welding jigs 1, 1 were made freely exchangeable between the exchange trolley 4 and the two welding devices 2, 2. .

In the drawing, reference numeral 5 denotes a transfer bar provided on the conveyance path 3, and the reciprocating motion of the transfer bar 5 transfers the automobile body W from the welding station A to the dispensing station B via an intermediate station C provided in the center of the conveyance path 3. To explain this in more detail, when the rear end of the transfer bar 5 is located at the welding station A or the intermediate station C, the front end of the transfer bar 5 is positioned at the intermediate station C or the delivery station B. A plurality of support members 6 for supporting the automobile body W are detachably attached to each end portion of the transfer bar 5.
is placed on the elevating frame 7, which is elongated in the longitudinal direction and is elevated and lowered by a plurality of cylinders 7a and guide bars 7b provided in the conveyance path 3, in the longitudinal direction along the guide rails 7c, 7c on both sides of the elevating frame 7. supported so as to be able to reciprocate, and further provided with a pair of front and rear first work receivers 8 ₁ , 8 ₁ and second work receivers 8 ₂ , 8 ₂ on both sides of the intermediate station C and the dispensing station B, respectively; When the transfer bar 5 is moved upwardly by the lifting frame 7 at the backward backward movement position, the welding jigs 1 of the automatic welding devices 2, 2 on both sides of the welding station A
The automobile body W held between the support member 6 at the rear end portion of the transfer bar 5 and the first work receivers 8 ₁ and 8 ₁ on both sides of the intermediate station C is received by the support member 6 at the front end portion of the transfer bar 5, and the vehicle bodies W are transported to the intermediate station C and the payout station B, respectively, by the forward movement of the transfer bar 5; The downward movement of the transfer bar 5 in the forward movement position moves each vehicle body W into the first position.
The workpieces are transferred to the workpiece receivers 8 ₁ , 8 ₁ and the second workpiece receivers 8 ₂ , 8 ₂ on both sides of the unloading station B, and in this state, the transfer bar 5 is moved back to prepare for the next workpiece transfer. did.

In the drawing, 7d indicates a synchronizing shaft provided below and along the lifting frame 7, and on the shaft 7d,
As shown in FIG. 6, each pinion 7f is attached to engage a rack 7e formed on each guide bar 7b,
The respective guide bars 7b are moved up and down in synchronization with each other via the shaft 7d, so that the elevating frame 7 can be maintained in a horizontal position.

In the drawing, D indicates a switching station for the exchange cart 4 provided in the middle of the conveyance path 3, and an exchange cart extending from the welding station A to the shunting station D is located on both sides of the transfer path 3 where the transfer fiber 5 is arranged. 4 running rails 9, 9, and a switch 10 on both sides of the switching station D.
A pair of front and rear shunting rails 11, 11 are provided for the shunting carriage 4, which are connected via a Each running rail 9 and each shunting rail 1
1, the switching rails 10b are rotatably provided by 90 degrees in a vertical position that matches each traveling rail 9 and a horizontal position that matches each shunting rail 11 by means of a cylinder 10a. Then, as shown in FIG. 6, each switching rail 10b is arranged so that when the lifting frame 7 is moved down, it is located slightly above this, and each switching rail 10b is placed in a horizontal position, and the exchange trolley 4 is switched. The switching station D can be moved in and out from the rails 11, 11, and the welding station can be moved between the switching station D and the welding station A along the traveling rails 9, with each switching rail 10b in a vertical position. It is possible to freely move back and forth between the two. Then, the transfer bar 5 is provided with an engaging member 5a that engages with the exchange cart 4 that is introduced from the exchange rails 11, 11 into the exchange station D, and the movement of the transfer bar 5 moves the welding station between the two welding stations. It was designed to move back and forth between stations A and D.

The exchange cart 4 is provided with casters 4c that are rotatable around a vertical axis at the four corners of its lower surface.
Each caster 4 is rotated by the rotation of each switching rail 10b.
c can be rotated.

By the way, the shunting station D can be provided at a sufficient distance from the welding station A so that a working space can be secured between the switching cart 4 on the shunting rails 11, 11 and the automatic welding device 2. Therefore, in the illustrated embodiment, the shunting station D is located forward of the intermediate station C so as to partially overlap therewith.

Furthermore, when the exchange trolley 4 enters and exits the exchange station D, the transfer bar 5 can be moved forward from the exchange station D so that the sideways position switching rail 10b does not interfere with the transfer fiber 5. However, if the transfer station D is arranged as described above, when the transfer bar 5 is moved forward from this point, the front end of the bar 5 will pass through the dispensing station B if the bar 5 is kept at the predetermined length. and protruded greatly in front of it,
A dead space corresponding to this protrusion length is created in front of the dispensing station B, and the line layout is restricted.

Therefore, in the illustrated transfer bar 5, the transfer bar 5 is made to be able to expand and contract between an extended state of the predetermined length and a contracted state of a shorter length, and the above-mentioned vehicle body transport is performed by reciprocating motion in the extended state and in the contracted state. The welding station is transported by the reciprocating movement of the welding station. To explain this in more detail, the transfer bar 5 is connected to a plurality of guide rollers 5 on guide rails 7c, 7c on both sides of the elevating frame 7, as shown in FIG.
a lower first bar 5 ₁ that is rotatably supported via b, and guide rails 5 c, 5 on the first bar 5 ₁ ;
The upper second bar ₅₂ is supported by c.
By moving the second bar ₅₂ back and forth through a rack 5f that engages with a pinion 5e on the output shaft of the telescopic motor _5d attached to the first bar 51, the transfer bar 5 is extended and contracted. 2nd bar 5
A pair of front and rear first and second locking pieces 5g ₁ on both sides of the front part of ₂ ,
5g ₂ and a pair of third and fourth locking pieces 5g ₃ and 5g ₄ in the front and back on both sides of the rear thereof, and the second bar 5 _{2 is sandwiched between the rear of the first bar 5 1 from} both sides. A fixed locking piece 5h on the front side and a movable locking piece 5j on the rear side as shown in FIG. 9, which is opened and closed by a cylinder 6i.
and when the transfer bar 5 is in the extended state, the fixed locking piece 5h is connected to the first locking piece 5 as shown in the second figure.
After g ₁ , the movable locking piece 5j is connected to the second locking piece 5g ₂
by engaging the front end of the second bar ₅₂ with the first bar.
When the transfer bar ₅ is in the contracted state, the fixed locking piece 5h is connected to the front end of the third locking piece _5g3 , and the movable locking piece 5j is connected to the fourth The second bar 52 is fixed to the first bar ₅₁ by engaging with the rear end _of the locking piece _5g4 .

Then, the engaging member 5a is attached to the rear end of the transfer bar 5 in the contracted state, that is, the rear end of the first bar ₅₁ , and is detachable from the joint member 4d protruding from the front end of the exchange cart 4. , by moving the transfer bar 5 in a contracted state to a position forward of the shunting station D, and inserting the changing cart 4 into the station D from the shunting rails 11, 11 on its side, the engagement member 5a The joint member 4d is engaged.

In this case, the bar 5 protrudes forward of the dispensing station B by the amount that the transfer bar 5 is contracted.
The length of the station B is shortened, and the dead space in front of the station B is reduced.

Further, as shown in FIG. ₈ , the first bar 51 is equipped with a drive motor 5m having a pinion 5l on an output shaft that meshes with a rack 5k fixed to the lifting frame 7.
The first bar 5 ₁ and therefore the transfer bar 5 are caused to reciprocate by the motor 5 m, and a pair of first and second reciprocating stoppers 12 ₁ and 12 ₂ are provided at the front of the lifting frame 7; 1st 2nd pair of rear front and rear
double-acting stoppers 13 ₁ and 13 ₂ are provided, and the second
The forward movement stopper 12 ₂ and the first backward movement stopper 13 ₁ are respectively movable upwardly and retractably.
The forward movement stopper 12 ₂ is made to protrude upward, and the first return movement stopper 13 ₁ is retracted downward, so that the second return movement stopper 12 ₂ and the second return movement stopper 13 ₂ are connected to each other.
The transfer bar 5 is reciprocated within a stroke range that is half of the vehicle body transfer _distance from welding station A to payout station B, which is regulated by
is retracted downward and the first reciprocating stopper 13 ₁ is projected upward, and the transfer bar 5 is moved between the forward movement position in front of the shunting station D regulated by the first forward movement stopper 12 ₁ and the first reciprocating stopper 13 1 . 1 double-acting stopper 13
The welding station A is made to reciprocate between the front and backward movement position regulated by ₁ .

In addition, in the illustrated example, the support legs 8a of each first work receiver ₈₁ provided on the intermediate station C are provided so as to be able to protrude in the front and rear directions inside the traveling rail 9 by cylinders 8b, and when the support legs 8a are brought down, the workpieces are In order to prevent the receiver ₈₁ from interfering with the traveling rail 9, the workpiece receiver ₈₁ can be rotated and retracted inside the traveling rail 9 by a rotary actuator 8c attached to the tip of the supporting leg 8a. 1
With the workpiece receiver 8 ₁ rotated and retracted, the supporting leg 8
When a is laid down, the workpiece receiver ₈₁ is stored in the inner space at a lower level than the traveling rail 9,
The exchange cart 4 can be moved in and out of the exchange station D and reciprocated with the welding station A without interfering with the workpiece receiver ₈₁ .

Next, the overall operation of the above embodiment will be explained.

During welding work, the automobile body W welded at the welding station A is transferred to the intermediate station C as described above by reciprocating the transfer bar 5 in the extended state.
The vehicle body W is transported from the welding station A by the forward movement of the transfer bar 5, and at the same time the car body W is transported from the welding station A by the forward movement of the transfer bar 5. The floor of the car body will be welded next using a set cart (not shown) from the station.
Wa, the roof Wb, and the side panel Wc are carried into the welding station A, and these parts are delivered to the welding jigs 1, 1 of the automatic welding devices 2, 2 on both sides to perform welding. If the delivery cart becomes long due to the installation of exchange station D in the middle, the delivery cart can be moved to welding station A as in the past.
If the welding cart is moved back and forth between the welding station A and the welding station B, welding will be completed before the welding cart returns to the welding station A, resulting in loss time, but the reciprocating stroke of the transfer fiber 5 is equal to Since it only takes half the time, the vehicle body can be transported efficiently without such loss time.

When replacing the welding jig 1, place an empty exchange cart 4 on the shunting rails 11, 11 on one side of the shunting station D, and place the welding jig to be used next on the shunting rails 11, 11 on the other side in advance. The exchange cart 4 loaded with the tools 1 and 1 is placed on standby, and first, the intermediate station C
The supporting legs 8a of the first work receiver ₈₁ are laid down, and the supports attached to the front and rear end portions of the transfer bar 5, that is, the front part of the first bar ₅₁ and the rear part of the second bar ₅₂ . After removing member 6,
The second bar 5 ₂ is advanced relative to the first bar 5 ₁ to bring the transfer bar 5 into a contracted state, and the transfer bar 5 is further moved forward from the switching station D, and then the switch 10 is moved forward. The switching rails 10b are rotated to the sideways position, and the empty exchange trolley 4 is introduced into the shunting station D from one side of the shunting rails 11, 11, and the joint member 4d at the front end is connected to the transfer bar 5. is engaged with the engaging member 5a at the rear end.

Next, after rotating each switching rail 10b to the vertical position, the transfer bar 5 is moved back toward the welding station A, and the exchange cart 4 is carried into the welding station A. The welding jigs 1, 1 of the welding devices 2, 2 are transferred to the exchange cart 4, and then the transfer bar 5 is moved to a position in front of the exchange station D, and the exchange truck 4 is transferred to the exchange station D. , and rotate each switching rail 10b to the sideways position again to send out the exchange trolley 4 onto the switching rails 11, 11 on one side, and transfer the switching rails 10b from the switching rails 11, 11 on the other side. The exchange trolley 4 loaded with the welding jigs 1, 1 to be used next is placed in the exchange station D, and the exchange trolley 4 is carried into the welding station A in the same manner as described above, and the automatic welding equipment 2 on both sides of the exchange trolley 4 are loaded into the exchange station D. , 2, transfer the welding jigs 1, 1 on the exchange trolley 4, then return the empty exchange trolley 4 to the exchange station D in the same manner as above, and replace it on one side or the other side. Shunting rail 1
The exchange cart 4 is sent out onto 1 and 11.

Next, the transfer bar 5 is returned to its extended state, and then support members 6 corresponding to the next model are attached to both sides, and finally, the support legs 8a of the first work receiver ₈₁ are erected to complete the replacement work.

(Effects of the Invention) As described above, according to the present invention, the exchange cart is carried from the exchange station in the middle of the conveyance path connecting the welding station and the delivery station to the welding station via the conveyance path, and the welding jig is It is possible to perform the replacement work efficiently, and unlike a system that has replacement rails on both sides of the unloading station, it is possible to secure a wide working space on both sides of the unloading station for transferring the workpiece to a hanger, etc., improving work efficiency. In addition, even if the distance between the welding station and the unloading station becomes long due to the presence of the shunting station, the workpiece is sequentially fed from the welding station to the unloading station via the intermediate station using the transfer bar, so the workpiece The transfer can be carried out efficiently without any loss time, improving productivity. Furthermore, since the exchange trolley is also transferred using the transfer bar, there is no need for a separate drive source for conveying the trolley, and the equipment can be saved. This has the effect of reducing costs.

[Brief explanation of drawings]

Fig. 1 is a plan view of an example of the embodiment of the present invention, Fig. 2 is a side view taken along the line - - in Fig. 1, Fig. 3 is a front view of the welding station during welding work, and Fig. 4 is transportation of the exchange cart. FIG. 5 is a front view of the welding station when the jig is replaced, and FIGS. 6 to 9 are enlarged cross-sectional views taken along the - line to - line in FIG. 2, respectively. It is a front view. A... Welding station, B... Unloading station, C... Intermediate station, D... Exchange station, 1... Welding jig, 2... Automatic welding device, 3... Transport path, 4... Exchange trolley , 5...transfer bar, 7...lifting frame, 9...travel rail, 10...switch, 11...shunting rail.

Claims (1)

[Claims] 1 Workpieces are welded by an automatic welding device equipped with a welding station and a delivery station in front of the welding station, and has welding jigs placed on both sides of the welding station, and the welded workpieces are removed from the welding station. The welding line is configured to be transported to the welding station via a forwardly extending transport path, and the automatic welding device is configured to transport an exchange cart on which a welding jig can be mounted to the welding station via the transport path. A transfer bar is provided on the transfer path, and the reciprocating motion of the transfer bar causes the workpiece to be delivered from the welding station via an intermediate station provided at the center of the transfer path. A switching station for the exchange trolley is provided in the middle of the transport path, and a switch for the exchange trolley extending from the welding station to the shunting station is provided on both sides of the transfer bar arrangement part of the transport path. A traveling rail and a shunting rail for an exchange bogie connected to the traveling rail via a switch are provided on both sides of the shunting station, and the exchange bogie is introduced from the shunting rail into the shunting station. Welding in a welding line, characterized in that an engaging member that engages with the transfer bar is provided on the transfer bar, and the exchange cart is reciprocated between the shunting station and the welding station by the movement of the transfer bar. Jig exchange device. 2. The transfer bar can be freely expanded and contracted between an extended state in which the rear end portion is located at the welding station or the intermediate station and a contracted state in which the front end portion is located at the intermediate station or the payout station. , the workpiece is transferred by reciprocating motion of the transfer fabric in the extended state, and the engagement member is attached to the rear end portion of the transfer fabric in the contracted state, and the transfer bar is moved from the shunting station in the contracted state. Replacing a welding jig in a welding line according to claim 1, characterized in that a replacement cart is reciprocated between the two stations by reciprocating from a front position toward the welding station. Device.