BACKGROUND OF THE INVENTION
1 FIELD OF THE INVENTION
[0001] The present invention relates to a spray painting system, and more particularly to
a spray painting system of a continous assembly line, the system including a plurality
of work machines for spray painting disposed side by side along a direction for conveying
a work object inside a spray painting booth.
2 DESCRIPTION OF THE RELATED ART
[0002] With conventional spray painting systems of the above-described type, as illustrated
in Fig. 5, inside a spray painting booth having a length ranging generally between
30 and 50 m, each of a plurality of work machines 6 is arranged movable within a predetermined
distance ℓ (usually about 1 m) in the object-conveying direction on a mounting frame
fixed on a floor surface of the booth. As guide mechanisms for moving the respective
machines differ from each other, it has been impossible to connect these guide mechanisms
so that the machines may share one common guide mechanism.
[0003] In recent years; however, there often arises the necessity of adjusting the postitions
of the work machines beyond the predetermined movable distances in order to dispose
each machine at the best position to cope with various changes in the kind or type
of paint, spraying guns, the shape of the work object and the other working conditions.
Obviously, the above-described conventional systems do not allow such work machine
position adjustments beyond the predetermined ranges. Then, as a means to overcome
this problem, it has been attempted to restrict the changes in the working conditions
per se thereby restricting the amount of position adjustment required by the changes.
Then, even after such modifications or arrangements in the work conditions, if the
positions of the work machines still need to be adjusted beyond the adjustable range;
then, the work machines are eventually dismounted from the floor surface and redisposed
on new locations with appropriate reinforcement of the floor surface of these new
locations as required for the machine installment. In such case, as the relocation
work takes a considerable time, it is necessary to suspend not only the production
line including these machines but also other production lines associated therewith
for many days. Consequently, the production efficiency of the entire line suffers
significantly.
SUMMARY OF THE INVENTION
[0004] For overcoming the above-described problem of the convention, a spray painting system
according to the first characterizing features of the invention, comprises: a plurality
of work machines disposed side by side along a direction of conveying a work object
inside a spray painting booth; and an upper rail and a lower rail for guiding the
work machines to move along the conveying direction, with each of the machines running
on the upper rail.
[0005] According to the second characterizing features of the invention, the rails guide
the movement of the machines in the object-conveying direction with the machines supported
on respective frames and each machine is detachably supported on the respective frame.
[0006] Functions and effects of the above features will be described next.
[0007] According to the first characterizing features of the invention, the same upper and
lower rails guide the movement of a plurality of work machines in the object-conveying
direction with the machines running on the upper rail.
[0008] Therefore, when there arises the necessity of changing the positions of the work
machines by a considerable amount to cope with changes in the work conditions such
as the type of paint, the spray guns, the shape of the object to be spray-painted
and so on, the position adjustment of the machines is readily possible without having
to change the disposing order of the machines and by a sufficient range determined
by the length of the rails.
[0009] Accordingly, the system of the invention can readily cope with frequent position
adjustment operations of the machines as required and also substantial changes in
the work conditions without requiring total relocation of the machines. Consequently,
the spray painting system of the present invention has achieved significant reduction
in the shutdown period of the production line which used to be required for troublesome
position adjustment or total relocation of the work machines, thus improving the entire
operation efficiency of the production line including this system as well as other
lines associated therewith.
[0010] With the second characterizing features of the invention, through selective detachment
of the machines each of which is detachably mounted on its frame, the system can change
the disposing order of the work machines in the object-conveying direction.
[0011] Further and other objects, features and effects of the invention will become more
apparent from the following more detailed description of the embodiments of the invention
with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Accompanying drawings Figs. 1 through 4 illustrate a preferred embodiment of a spray
painting system according to the present invention; in which,
Fig. 1 is a plane view of the entire system,
Fig. 2 is a cross sectional view of the system,
Figs. 3 and 4 are an enlarged side view and an enlarged front view showing a moving
construction of the system, respectively.
Fig. 5 is a plane view showing a conventional spray painting system.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] Preferred embodiments of the invention will now be described in particular with reference
to the accompanying drawings.
[0014] Referring to Figs. 1 and 2, a tunnel-like spray painting booth 1 accommodates a conveyor
device 1 for conveying an object 2 (an automobile body in the instant embodiment),
an overhead outlet vent 4 for downwardly discharching a ventilation air and a demister
5 for eliminating spray mist contained in exhaust air by traping the mist in cleaning
water. Inside this booth 1, there are installed a purality of work machines 6 for
the spray painting, with the machines being disposed side by side along a direction
of conveying the object 2 inside the booth.
[0015] The work machines 6 comprise various kinds such as one-hand robbot 6a for opening
and closing doors of the object 2, i.e. automobile body, a further one-hand robbot
6b for controlling a spray gun 7a to spray-paint interior surfaces of the object
2, a side-face spraying machine 6c for vertically moving a spray gun 7b to spray-paint
side outer surfaces of the object 2, an upper-face spraying machine 6d for controlling
rotary, reciprocating and vertical linear movements of an arm 7d equipped with a spray
gun 7c so as to spray-paint upper surfaces of the object, and a touchup spray painting,
one-hand robbot 6e for controlling a further spray gun 6e to effect a touchup spray-paint
operation on the object.
[0016] These work machines, as shown in Figs. 3 and 4, are detachably mounted on frames
8 of the idential construction; and each frame is movable by drive force along the
object-conveying direction.
[0017] For moving the frames 4, as one common guide mechanism shared by and for independently
guiding the movements of the frames 4, there are provided an upper rail 9a and a lower
rail 9b at upper and lover portions of a side wall 1a of the booth. On the other hand,
each frame 4 has a first roller 10a for rolling on an upper face of the upper rail
9a with the weight of the frame 8 being supported by the rail 9a, a pair of second
rollers 10b which strides across the upper rail 9a and a pair of third rollers 10c
which strides across the lower rail 9b.
[0018] Further, for a chain 11 layed along the upper rail 9a, the frame 8 also has a pair
of free sprockets 12a engageable with the chain 11, a drive sprocket 12b which comes
into engagement with an inner side of the chain 11 which is formed like a reversed
letter U- shaped as being entrained about the two free sprockets 12a, and a motor
14 for driving the drive sprocket 12b via a reduction mechanism 13.
[0019] In operation, with the drive of the motor 14, the frame 8 (i.e. the work machine
6 mounted on this frame) is self-movable along the object-conveying direction within
the range determined by the length of the upper and lower rails 9a and 9b, while the
chain 11 acting as resistance againt react ion force associated with the movement
of the frame 4. In this way, if the setting position of the work machine 6 has be
changed to cope with various changes in the operating conditions such as in the type
of paint, the spray guns 7a, 7b, 7c and 7e and/or in the shape of the object 2, i.e.
the automobile body, the position adjustment is readily possible by selectively and
independently causing the machines 6 to self-move along the object-conveying direction.
[0020] Moreover, as described hereinbefore, since the work machines 6 are detachably mounted
on the respective self-propelling type machine frames of the identical construction,
re-arrangement of disposing order of the machines 6 in said direction is also readily
possible by selectively replacing or relocating the machines 6 relative to the frames
8.
[0021] On a lateral side of the spray painting booth 1, an operator box 15 having a length
extending over the entire length of the rails 9a and 9b is integrally attached to
the booth side wall 1a; and the booth side wall 1a has a window 16 for allowing an
operator inside an operator chamber 15a of the box 15 to inspect and watch the spray
painting operation taking place inside the booth.
[0022] Inside the operator box 15, a partition 11 is provided for forming an upper section
15b separately from the operator chamber 15a. The upper section 15b accommodates paint
hose-cable means 18 such as paint hoses, electric cables and pressure-air hoses for
feeding paint, electricity and pressure air to the respective work machines 6; flexible
means 19 such as flexible cable racks for allowing movements of the work machines
6 along the conveying direction and further the upper rail 9a and the chain 11.
[0023] The upper section 15b further accommodates a shaft 14a for operatively connecting
the motor 14 and the drive sprocket 12b and an opening S for inserting the hose-cable
means 18 therethrough.
[0024] Inside the operator chamber 15a, there is provided a remote control panel 22 for
remote-controlling the work machines 6. At a lower section 15c sectioned by the partition
23 from the operator chamber 15a inside the operator box 15, there are accommodated
control panel means 24 such as electric control panels and pressure-air control panels.
[0025] The operator chamber 15a is connected with a duct 21 having a dumper 20 for forcibly
introducing ventilatin air from a air feed chamber 4a through the overhead outlet
vent 4 into the chamber 15a.
[0026] Numeral 25 denotes a grating floor used for e.g. a system maintenance operation.
This grating floor 25 is provided only at a certain region inside the booth along
the object-conveying direction. For maintenance operations of the work machines 6,
the machine 6 to be maintained is driven to self-move to the region of the grating
floor 25.
[0027] That is, since the grating floor 25 is provided only at a certain region inside the
booth, cleaning operation of this grating floor 25 to eliminate excess paint adhered
thereto is required less frequently than the conventional system in which the grating
floor is provide over the entire booth floor.
[0028] Further, it is also conceivable to render this grating floor 25 movable in the object-conveying
direction. In this case, the setting location of the grating floor 25 can be changed
in accordance with the necessity and convenience.
[0029] The types of the work implements used for spray painting operation are not limited
to those described in the foregoing embodiment.
[0030] Further, the object 2, in place of the automobile body, can be any kind such as a
casing of a home electric appliance or a train body and so on.
[0031] The invention may be embodied in other specific forms without departing from the
spirit or essential characteristics thereof. The present embodiments are therefore
to be considered in all respects as illustrative and not restrictive, the scope of
the invention being indicated by the appended claims rather than by the foregoing
description and all changes which come within the meaning and range of equivalency
of the claims are therefore intended to be embraced therein.
1. A spray painting system having a plurality of work machines (6) disposed side by
side along a direction of conveying a work object (2) inside a spray painting booth(1),
characterized by:
an upper rail (9a) and a lower rail (9b) for guiding the work machines (6) to move
along said conveying direction, with each of the machines (6) running on said upper
rail (9b).
2. A spray painting system according to Claim 1,
characterized in that
said rails (9a, 9b) guide the movement of the machines (6) in the object-conveying
direction with said machines (6) supported on respective frames (8), each machine
(6) being detachably supported on the respective frame (8).
3. A spray painting system according to Claim 2,
characterized in that
said frame (8) includes a first roller (10a) for rolling on an upper face of said
upper rail (9a) with the weight of the frame (8) being supported by said upper rail
(9a), a pair of second rollers (10b) which strides across said upper rail (9a) and
a pair of third rollers (10c) which strides across said lower rail (9b).
4. A spray painting system according to Claim 3,
characterized in that
said frame(8) is driven via a chain 11 layed along said upper rail (9a).