Floor coating agent applying machine

A floor coating agent applying machine having propelling wheels attached to a machine body and an applying device for applying floor coating agent onto a floor surface by an applying member. The applying device is vertically movably mounted on the machine body between a free-lift state where the device is lowered, by a dead weight thereof, relative to the machine body to place the applying member into pressure contact with the floor surface and a lift-up state where the applying member is lifted up away from the floor surface. A control member is provided for selectably bringing the applying device into the free-lift state or the lift-up state.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a floor coating agent applying machine 
having propelling wheels and an applying device for applying floor coating 
agent onto a floor surface by means of an applying member. 
2. Description of the Related Art 
A floor coating agent applying machine of the above-noted type is known 
from e.g. a Japanese laid-open patent gazette No. 63-315169. In this 
machine, the applying device is fixedly attached to a machine body. 
With the above-described conventional machine, however, setting and 
adjustment of applying pressure of the applying member must be effected by 
appropriately setting relative height between the applying member of the 
applying device and the propelling wheels. This tends to be difficult 
because of manufacturing and assembly errors and/or tolerances often 
present in the various elements constituting the applying device and the 
wheels. As a result, the actual applying pressure of the applying member 
often deviates from a desired value. Further, when the machine, i.e. its 
propelling wheels and applying member travel on an uneven floor surface, 
there inevitably occurs change in the height of the machine with respect 
to the floor face, which change results in change in the applying 
pressure. These effects, as combined, will render the finish condition 
poor. 
Accordingly, the primary object of the present invention is to provide an 
improved floor coating agent applying machine which is capable of 
maintaining the applying pressure at a proper value throughout an applying 
operation irrespectively of unevenness in a floor surface and which is 
superior in controllability as well. 
SUMMARY OF THE INVENTION 
For accomplishing the above-described object, a floor coating agent 
applying machine, according to the present invention, comprises: machine 
propelling wheels attached to a propelling machine body; an applying 
device for applying floor coating agent onto a floor surface by means of 
an applying member; wherein the applying device is vertically movably 
mounted on the machine body between a free-lift state where the device is 
lowered, by a dead weight, relative to the machine body to place the 
applying member into pressure contact with the floor surface and a lift-up 
state where the applying member is lifted up away from the floor surface 
and a control member is provided for selectably bringing the applying 
device into the free-lift state or the lift-up state. 
Functions and effects of the above construction will be described next. 
If the control member is operated to bring the applying device into the 
lift-up state, the applying member is lifted up away from the floor 
surface, whereby the machine can travel and maneuver smoothly without 
unnecessary friction or contact between the applying member and the floor 
surface. On the other hand, if the control member is operated to bring the 
applying device into the free-lift state, the applying member is brought 
into pressure contact with the floor surface by the dead weight of the 
applying device, thereby enabling an applying operation. 
The contact pressure, as the applying pressure, between the applying member 
and the floor surface is determined by the dead weight of the applying 
device. Thus, even if there exist some manufacturing and assembly errors 
or tolerances in the propelling wheels and/or the applying device, the 
applying pressure can be maintained properly by appropriately determining 
the dead weight of the applying device. Further, when the propelling 
wheels and the applying member travel on an uneven floor surface, i.e. a 
ridge or a recess in the surface, the applying device will freely move up 
or down relative to the machine body by an amount depending on the 
magnitude of and shape of the unevenness, whereby the applying pressure 
can still be maintained properly. 
Advantageously, the applying device is made capable of dead-weight rolling 
action. This feature is advantageous in that the applying device can swing 
to automatically follow the unevenness in the floor surface with respect 
to the propelling machine body whereby the applying pressure can be 
maintained properly through the entire working face of the applying 
machine. 
In summary, according to the present invention, the applying pressure of 
the applying device is obtained by the dead weight of the applying device 
per se. Therefore, through appropriate setting of the dead weight which 
setting is much easier than control of manufacturing and assembly errors 
and tolerances, the applying pressure can be constantly maintained at a 
proper value irrespective of possible unevenness in the floor surface to 
be treated. Consequently, the machine can assure superior finish all the 
time. 
Moreover, because of the control member used for selectably providing the 
free-lift state and the lift-up state of the applying machine which latter 
state is convenient and useful for e.g. a turning operation of the 
propelling machine, the controllability and maneuverability of the machine 
has been improved as well. 
Incidentally, although it is conceivable to adapt the applying device only 
to move upwards in the free-lift state, the above-described feature of the 
rolling function will be more advantageous in actuality. 
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.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Preferred embodiments of a floor coating agent applying machine relating to 
the present invention will be particularly described hereinafter with 
reference to the accompanying drawings. 
As shown in FIGS. 1 and 2, a floor coating agent applying machine includes 
a propelling type machine body 4, a pair of right and left propelling, 
i.e. driving front wheels 1, 1, a pair of right and left non-driving, i.e. 
free rotation rear wheels 2, 2, a steering handle 3 and a coating agent 
tank T disposed at a rear position of the machine body 4. 
At a forward end of the machine body 4, there are attached a plurality of 
feed nozzles 6 . . . , disposed side by side in the transverse dirction of 
the machine body 4. These feed nozzles 6 . . . are connected with the tank 
T through an electric pump P and a feed tube 5 incorporating therein a 
relief valve RV, so that floor coating agent or liquid is fed supplied 
from the tank T to the respective feed nozzles 6. Further, the machine 
body 4 also mounts an applying device 8 including an applying member 7 
positioned rearwardly of the nozzles 6 and an electric motor M1 and so on. 
The machine body 4 further mounts an air guide member 10 defining a hot 
air discharge opening 9 oriented downwards rearwardly of the applying 
member 7. This air guide member 10 is adapted for introducing therein air 
from an electric blower B1 disposed above the member 10 and for 
discharging this air after heating thereof by an unillustrated electric 
heater through the hot air discharge opening 9 onto the floor surface. At 
a bottom of the machine body 4, there is attached a pipe 12 which forms a 
plurality of downwardly-oriented blower openings 11 . . . disposed side by 
side rearwardly of the hot air discharge opening 9 along the transverse 
direction of the machine body 4. Also, a further electric blower B2 is 
attached to a rear region of the machine body 4, so that the blower B2 
feeds air flow of room temperature through an air feed tube 13 to the pipe 
12. As a result, the room-temperature air is distributed and discharged 
through all the discharge openings 11 . . . downwardly to the floor 
surface. A machine-propelling electric motor M2 is attached to a front end 
region of the machine body 4 for driving the right and left front wheels 
1, 1 through a front axle 14 and a transmission belt 15. A control unit 16 
is attached to a rear position of the machine body 4 for controlling the 
electric pump P, an electromagnetic valve V, the electric blowers B1 and 
B2 and the electric motors M1 and M2. These devices and members together 
constitute the self-propelled type floor coating agent applying machine. 
In operation, a thermoplastic resin type floor coating solution is 
discharged and reserved in the tank T, and the machine is self-propelled 
on a target floor formed of stone, wood, concrete, various kinds of 
artificial materials or the like. Then, in automatic response to this 
propelling action of the machine body, the pump P withdraws the floor 
coating solution from the tank T and feeds the solution evenly to all the 
feed nozzles 6 . . . while returning excess solution via the relief valve 
RV to the tank T. More specifically, each of the feed nozzles 6 . . . 
feeds and discharges a predetermined amount of the solution onto the floor 
surface and then the applying member 7 applies the discharged solution 
over the floor surface. Next, the hot air through the hot air discharge 
openings 9 heats the solution applied by the applying member and 
evaporates water content therein for plasticizing the same. Then, the 
room-temperature air flow through the air discharge opening 11 cools and 
cures the solution. 
The construction of the applying device 8 will be more particularly 
described next. 
As shown in FIG. 1, the applying member 7 is attached through an attaching 
plate 19 to a lower face of an applying-device frame 18 made of plate 
metal. This attaching plate 19 has its rear end attached to a frame 
portion 4a of the machine body 4 through a pair of right and left 
connecting rubber elements 17, 17. Further, on the upper face of the frame 
18, there is mounted the electric motor M1. Further, a lever type control 
member 23a or 23b is attached to a control member support portion 4b of 
the machine body 4 through a pivot shaft 22 acting also as a control 
member link shaft. Then, with a manual pivotal operation on this control 
member 23a (23b), there is selectively provided an operative, free-lift 
state of the applying device 8 or an inoperative, lift-up state of the 
same for storage. 
More particularly, when either of the right and left control members 23a or 
23b is forwardly pivoted on the pivot axis in the longitudinal direction 
of the machine body 4, the applying device 8, by its dead weight, 
elastically deforms the connecting rubber elements 17 and moves downwards 
relative to the machine body 4. With this, the applying member 7 is 
brought into pressure contact with the floor surface at a predetermined 
pressure of about 50 g/cm.sup.2 determined by the effective applying area 
of the applying member 7 and also by the dead weight of the applying 
device 8. If the propelling wheels 1, 2 and the applying member 7 travel 
on some unevenness present in the floor surface, due to elastic 
deformation of the connecting rubber elements 17, some looseness in 
connection resultant from free pivotal motions of the control members 23a 
and 23b with respect to the attaching portion 4b, reaction received by the 
applying member 7 from its contact with the floor face and also to the 
dead weight of the applying device, the applying device 8 effects a free 
lift or rolling motion relative to the machine body 4. As a result, the 
machine can applying the coating agent uniformly to the floor surface 
despite the floor surface unevenness, i.e. undulations and/or slants. This 
is the free-lift state of the applying device 8. 
On the other hand, as shown in FIG. 3, if the control member 23a or 23b is 
operated in the opposite direction until both these control members 23a 
and 23b move to positions rearwardly of the machine body where a free of 
the operated control member 23a (23b) comes into contact with a stopper 
pin 24 attached to the control member support portion 4b, this operating 
force is transmitted through a link rod 21 and so on to lift up the 
applying device 8 while deforming the connecting rubber elements 17. This 
is the lift-up state of the applying device where the applying device 8 is 
lifted away from the floor surface for facilitating the propulsion of the 
machine body 4 and is maintained at this state with the device 8 being 
supported by the stopper pin 24. 
As shown in FIG. 4, for enabling the electric motor M1 to drive the 
applying member 7, the applying-device attaching plate 19 is attached to 
the frame 18 through a plurality of connecting rubber elements 25 . . . 
disposed vertically relative to the machine body. Further, on the upper 
face of the attaching plate 19, there is mounted a bearing holder 18 
supporting therein ball bearings 27 and a rotary cam 28 surrounded by the 
bearings 27. The rotary cam 28 is fitted on a motor output shaft 29 so as 
to be rotatably driven by the motor M1 about a vertical axis X2 which is 
displaced relative to an inner ring rotary axis X1 of the ball bearings 
27. In operation, as the electric motor M1 is driven, because of the 
resultant rotational force of the rotary cam 28 and of the eccentric 
arrangement of the axes X1 and X2, the applying-member attaching plate 19 
rotates about the vertical axis X2 so that the applying member 7 rotates 
about this vertical axis X2 along the floor surface. Further, with the 
rotary motion of the applying-member attaching plate 19, this motion 
causes all the connecting rubber elements 25 . . . to pivot at or relative 
to their top ends fixed to the frame 18 while their lower ends fixed to 
the attaching plate 19 effect vertical motion. Consequently, the applying 
member 7 effects a vertical swing motion. 
Some alternate arrangements will be specifically described next. 
The front wheels can comprise free rotation type instead of the 
motor-driven type disclosed in the foregoing embodiment, so that the 
machine body 4 can be propelled manually. 
It is conceivable to arrange so that the applying member 7 effects only 
either the rotary motion or the vertical swing motion. Further, the 
applying member 7 can be adapted to effect neither the rotary motion nor 
the vertical swing motion so that the member 7 applies the agent while 
sliding on the floor surface with the propelling action of the machine 
body. 
For the free-lift and dead-weight rolling arrangement of the applying 
device 8, any other convenient means should be apparent for one skilled in 
the art rather than the connecting rubber elements 17 and 20. For 
instance, for the attachment to the machine body 4 and for the operative 
connection with the control members 23a and 23b, various attaching or 
connecting means such as pivot shafts, connecting pins with corresponding 
slots, hinges, chains or cables can be employed depending on the 
convenience and necessity. 
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.