U.S. patent number 3,777,834 [Application Number 05/225,195] was granted by the patent office on 1973-12-11 for magnet vehicle.
This patent grant is currently assigned to Hitachi Metals, Ltd.. Invention is credited to Yoshihiko Hikita, Michito Hiraoka.
United States Patent |
3,777,834 |
Hiraoka , et al. |
December 11, 1973 |
MAGNET VEHICLE
Abstract
A magnet vehicle supportedly adhered to and adapted to run over
an inclined wall surface of a structural member made of a strong
magnetic material such as iron and steel, characterized in that
said vehicle can be altered of its direction of travel as desired
on said surface.
Inventors: |
Hiraoka; Michito (Ageo,
JA), Hikita; Yoshihiko (Fukaya, JA) |
Assignee: |
Hitachi Metals, Ltd. (Tokyo,
JA)
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Family
ID: |
26376515 |
Appl.
No.: |
05/225,195 |
Filed: |
February 10, 1972 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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36753 |
May 13, 1970 |
3682265 |
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Foreign Application Priority Data
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May 16, 1969 [JA] |
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44-37383 |
Aug 1, 1969 [JA] |
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44-60410 |
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Current U.S.
Class: |
180/9.44; D12/1;
114/222; 335/296; 180/901; 451/93 |
Current CPC
Class: |
B62D
55/265 (20130101); B60L 13/04 (20130101); H01F
7/20 (20130101); B61C 15/04 (20130101); B23K
37/0264 (20130101); B63B 59/10 (20130101); Y02T
30/00 (20130101); Y10S 180/901 (20130101); Y02T
30/10 (20130101) |
Current International
Class: |
B60L
13/04 (20060101); B61C 15/00 (20060101); B61C
15/04 (20060101); B63B 59/10 (20060101); B63B
59/00 (20060101); B62D 55/18 (20060101); B62D
55/265 (20060101); B23K 37/02 (20060101); H01F
7/20 (20060101); B62d 011/00 (); B62d 055/00 () |
Field of
Search: |
;180/9.44,9.48,9.38,1VS,9.2R ;114/222 ;335/229,296 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Betts; Kenneth H.
Assistant Examiner: Pekar; John A.
Parent Case Text
This is a divisional application of copending U.S. application Ser.
No. 36,753, filed May 13, 1970, now U.S. Pat. No. 3,682,265.
Claims
We claim:
1. A magnet vehicle for operating on the surface of iron or steel
bodies, comprising a frame, a pair of endless track means located
on either side of said frame adapted to be in contact with the
surface for frictional driving of the vehicle, lateral magnet means
provided between the upper run and the lower run of said endless
track means, central magnet means disposed centrally of said frame
and assisting said lateral magnet means to keep the vehicle
attracted on the surface by the magnetic force thereof,
displacement means for displacing said central magnet means
downwardly relative to said endless track means so that said
magnetic vehicle can be supported on said surface solely by said
central magnet means, steering means for rotating the remainder of
said magnet vehicle relative to said central magnet means when said
magnet vehicle is supported solely by said central magnetic means,
and motor means for driving said endless track means.
2. A magnet vehicle as defined in claim 1 characterized in that
said steering means for rotating the remainder of said vehicle
relative to the central magnet means includes a ring gear fitted
around the central magnet means and planetary gear means secured at
one end of a shaft to be meshed with said ring gear, said shaft
being rotatably journalled in a portion of said frame, another gear
means secured at the other end of the shaft, and a motor for
driving said another gear means.
Description
The present invention relates to a steered magnet vehicle
supportedly adhered to a vertical or inclined wall surface of a
structural member made of a magnetic material such as iron and
steel and adapted to travel over said surface for various
operations such as painting, inspection of welded portions and so
on, various devices for such purposes being mounted thereon.
Heretofore, it has been necessary to construct platform for
operators by, for example, combining wooden bars or rods, or
otherwise to suspend gondola or cradle or the like from above, when
painting or inspecting ships or large buildings. Thus, the
operators had to work by hand on such platform or in such gondola
located at a considerable height. For this reason, the operation
was dangerous and, in addition to this, the efficiency of operation
was extremely low.
To overcome the above disadvantages, various steered magnet
vehicles have been proposed. However, such magnet vehicles
heretofore proposed have proved to be not satisfactory, for
example, in that, when the magnet vehicle is driven over a surface
having a certain curvature instead of a flat plane of a structural
member, it was not possible to obtain a sufficient adhesion force
for supporting its weight and further that it tended to sometimes
damage the operation surface due to the contact pressure exerted
between the vehicle and the operation surface. Thus, any
satisfactory magnet vehicle has not been put to a practical
use.
In case of steered magnet vehicles heretofore proposed, they are
adhered to an operation surface by permanent magnet means and/or
electromagnet means mounted thereon, and driven by driving or
magnetic belts provided on both sides of the vehicle, which belts
being driven by electric motors. In case of changing the direction
of travel of the magnet vehicle of this type, it was done by
driving only the belts located on one side of the vehicle, while
the other belts located on the opposite side being stopped or
reversely driven, whereby turning the magnet vehicle in a certain
radius of turn. However, when the vehicle is supported on an almost
vertical wall surface, it had the tendency of slipping at the
contact area either of the right or left belts during the turn of
the vehicle owing to the change in the contact pressure between the
vehicle and the wall surface. Accordingly, remarkable skill was
required to turn the magnet vehicle exactly in the desired
direction, and it required a relatively large radius of turn and a
long time to accomplish turning of the vehicle.
It is therefore an object of the present invention to provide a
steered magnet vehicle which can alter its direction of travel with
high reliability, with ease, in a remarkably short while in
comparison with the conventional ones and even in a considerably
restricted area.
In accordance with the present invention, there is provided a
steered magnet vehicle comprising central magnet means, lateral
magnet means, the gap between the lower end of the electromagnet
means and an operation surface being adjusted in accordance with
the curvature of said operation surface in order to maintain a
predetermined adhesion force therebetween, driving endless belt
means adapted to be driven by driving pulley means, take-up pulley
means and guide pulley means mounted on frame members, planetary
gear means associating with a gear fixedly secured to said central
magnet means for altering the direction of travel of the magnet
vehicle.
In accordance with another embodiment, the invention is a steered
magnetic vehicle comprising central magnet means mounted on an
upper frame and including means for automatically adjusting the
vertical movement of the central magnet means in order to maintain
a constant adhesion force between the vehicle and the surfaces upon
which it rides, a pair of endless track means disposed on opposite
sides of said frame for frictional driving of the vehicle, lateral
magnet means disposed between the upper and lower runs of said
track means, and a pair of motor means each adapted to drive a
different one of said track means to enable steering thereof.
Other objects, features and advantages of the present invention
will become apparent to those skilled in the art from the following
detailed description and attached drawings on which, by way of
example, only the preferred embodiments of the present invention
are illustrated, in which:
FIG. 1 is a plan view illustrating one embodiment of the steered
magnet vehicle according to the present invention.
FIG. 2 is a side view of the vehicle shown in FIG. 1.
FIG. 3 is an enlarged view in section on the line III--III shown in
FIG. 1.
FIG. 4 is a longitudinal, sectional view illustrating lateral
magnet means in detail.
FIG. 5 is a plan view illustrating another embodiment of the magnet
vehicle according to the present invention.
FIG. 6 is a side view illustrating the magnet vehicle of FIG. 5 in
its vertical section.
FIGS. 7 and 8 are sectional views illustrating in detail a steering
means incorporated in the magnet vehicle shown in FIG. 5.
One preferred embodiment of the present invention will now be
described hereinunder merely by way of example with reference to
FIGS. 1 through 4. In this specification it is contemplated that
dashed reference numeral means members disposed at the right-hand
side with respect to the longitudinal center line of the
vehicle.
1 and 1' and 2 and 2' are driving endless V-belts which are wound
around drive pulleys 3 and 3', take-up pulleys 4 and 4', guide
pulleys 5 and 5' and small pulleys 6 and 6' and adhered to the side
wall or the under surface of the structural body 38 made of iron or
steel and serve to drive the magnet vehicle. The aforementioned
driving endless V-belts are driven through rotation of the driving
pulleys 3 and 3'. 7 is a support member for said driving pulleys of
non-magnetic material. The driving pulleys supported in said
support member 7 by means of bearings 8 and 8' are associated with
driving motors 9 and 9' in said driving pulley support member 7 via
couplings 10 and 10', and they are driven independently by means of
said driving motors 9 and 9'.
The driving motors 9 and 9' are operated by remote control means
and are preferably of the electric or pneumatic type for the
purpose of decreasing the weight of the vehicle. 11 and 11' are
side wall members symmetrical with respect to the longitudinal axis
of the vehicle, and comprise respectively lateral magnet means 13
and 13' and three pairs of guide pulley means 14 and 14'.
The lateral magnet means 13 and 13' consist respectively of frames
12 and 12' of non-magnetic material, permanent magnets 15 and 15',
upper heel pieces 17 and 17' and lower heel pieces 18 and 18'.
Guide grooves 19 and 19' are provided for receiving the driving
belts 1 and 1' and 2 and 2' on the upper surface of the frames 12
and 12' and on the lower surface of the lower heel pieces 18 and
18', respectively.
The guide pulley means 14 and 14' are provided in the frames 12 and
12' in three pairs on the right and left of the vehicle, and
comprise guide pulleys 5 and 5', support frames 20 and 20' for said
guide pulleys, bolts 21 and 21' for suspending the support frames
20 and 20' from the frames 12 and 12' and springs 23 and 23'
provided between said frames 12 and 12' and said support frames 20
and 20' and disposed around the bolts 21 and 21' and nuts 22 and
22'.
24 is a central magnet means which is comprised of upper frame 25,
worm 26, worm wheel 27, cover 28 for these members, shaft 30
including a screw 29 adapted to be vertically displaced through the
rotation of said worm wheel 27 and magnet 31 fused to the lower end
of said shaft 30. 32 is a coil, which is mounted within a yoke 34
by means of a shaft 33. 35 is a reduction and lift motor which is
associated with the worm 26 via the coupling 36. A limit switch 37
is attached to the yoke 34 cooperating with the reduction and lift
motor 35 so that the distance between the electromagnet 31 and the
structural member 28 of iron or steel may be maintained constant.
There are provided on the lateral frames 12 and 12', a plurality of
guide rollers 39 and 39', respectively, so that the electromagnet
31 may be vertically moved along a suitable groove formed in the
yoke 34 when it is moved upward or downward.
40 is a support frame of non-magnetic material for supporting the
take-up pulleys 4 and 4' and the small pulleys 6 and 6'. Take-up
pulleys 4 and 4' are mounted thereon in the manner that their
location may be adjusted with ease. 41 is a painting nozzle mounted
on the upper frame 25.
Said frame pulley support frame 7, lateral frames 12 and 12', upper
frames 25 and support frame 40 are respectively interconnected with
each other by suitable means such as bolts and nuts, and they
constitute the magnet vehicle together with the aforementioned
various elements and means.
In the above arrangement, when the magnet vehicle is placed upon a
side wall or under surface of the structural member 38 by means of
suitable means such as a crane, the lateral magnet means 12 and 13'
adhere to the surface of the structural member 38 via the driving
V-belt 1 and 1' and 2 and 2' guided by the grooves 19 and 19'
formed in the upper surface of the frames 12 and 12' and the lower
heel pieces 18 and 18'. Subsequently, when the electromagnet 31 is
activated by the limit switch 37 in association with the mechanism
comprising the reduction and lift motor 35, coupling 36, worm 26,
worm wheel 27, screw 29 and shaft 30, the magnet vehicle then
adheres to and is firmly supported on a side wall or under surface
of the structural member 38.
After the vehicle adheres to and is supported on the structural
member, it is operated by means of remote control means (not shown)
mounted on the vehicle and a control board (not shown) provided on
or away from the structural member 38. When it is required to
advance the vehicle straight, the two driving motors 9 and 9' are
rotated at the same speed, whereupon the driving pulleys 3 and 3'
are rotated intermediary of the respective couplings 10 and 10' to
advance the driving V-belts 1 and 1' and 2 and 2'. When it is
required to change the direction of advance, only one of said two
driving motors 9 and 9' is driven.
During the movement of the vehicle, the entire weight of the
vehicle and various devices mounted thereon are supported by either
of or both of the central magnet means 24 and the lateral magnet
means 13 and 13'. It is preferable that the gap between the
respective heel pieces 18 and 18' of the lateral magnet means 13
and 13' and the surface of the structural member 38 be in the
magnitude of about 1-3 mm. Such magnitude of gap is achieved by the
driving V-belts 1 and 1' and 2 and 2' fitted in the grooves 19 and
19' formed in the heel pieces 18 and 18'. The springs 23 and 23' of
the guide pulley means 14 and 14' act in accordance with the
curvature of the structural member 38 so that said gap between the
lower surface of the heel pieces 18 and 18' and the surface of the
structural member 38 may be maintained constant.
In case of the central magnet means 24 on the other hand, it is
also preferable to maintain the gap between the electromagnet 31
and the structural member 38 at a predetermined optimal value. For
this purpose, there are provided on the lateral wall of the
electromagnet 31 a plurality of limit switches 37 for normally or
reversely rotating the reduction and lift motor 35 and thereby
displacing the electromagnet 31 upwardly or downwardly. Thus, the
gap between the electromagnet 31 and the structural member 38 can
be automatically adjusted at a given constant value, in spite of
the fact that the curvature of the structural member 38 varies
along the pass of the vehicle. The magnet vehicle can be removed
with ease from the surface of the structural member 38 by simply
supporting the magnet vehicle by suitable means such as a crane, or
otherwise by switching off the limit switches 37 to their
non-operable positions and abutting the yoke 34 of the
electromagnet 31 to the structural member 38 and thereby cutting
off the electric current and removing the magnetic force exerted by
the lateral magnet means 13 and 13' to the structural member
38.
Another preferred embodiment of the present invention will now be
described below with reference to FIGS. 5 through 8. In the
drawings, 101 is an electromagnet, 102 is a coil for said
electromagnet 101, and 103 is a central frame for interlocking and
supporting various elements of the vehicle. 104 and 104' are
driving wheels while 105 and 105' are driven wheels. 106 and 106'
are lateral frames. 107 is an air cylinder means for vertically
moving the electromagnet 101, and comprises an air cylinder 108
secured to the frame 103, a piston 109 adapted to be slidingly
moved within said cylinder 108 and a rod 110 fixed to said piston
109 at one end and to said electromagnet 101 at its opposite end.
111 and 112 are inlet and exhaust ports of compressed air used for
vertically moving the piston 109, and connected to a pipe
respectively. 113 is a bearing in which the rod 110 is slidingly
moved. 114 is the lower end portion of the heel piece of the
electromagnet 101. 115 is a steering means and it comprises a
driving motor 116, bevel gears 117 and 118, a shaft 119 having the
bevel gear 118 secured at one end, a spur gear 120 secured at the
other end of said shaft 119 and large gear 121 to be engaged with
said spur gear 120 and fixedly mounted on the electromagnet 101.
122 is a bearing for the shaft 119 provided in the in the center
frame 103, and 123 is a guide bore for said shaft 119 provided in a
bracket 124. 125 and 125' are driving belts wound around the
driving wheels 104 and 104' and the driven wheel 105 and 105'. 126
and 126' are driving motors mounted on a support frame 127 provided
in the center frame 103, which motors are arranged to drive the
driving wheels 104 and 104', respectively, and thus, via driving
belts 125 and 125', the magnet vehicle is driven. 128 is a gap
existing between the surface 129 of a structural member made of
iron or steel and the adhesion end 114.
In the arrangement of the present invention, the force for adhering
the magnet vehicle to the surface of the structural member is
exerted by the electromagnet 101 and permanent magnet means
incorporated in the lateral frame 106 and 106'. In case that the
total weight of the magnet vehicle itself and associating devices
mounted thereon is relatively low, it is possible to dispense with
the permanent magnet means incorporated in the lateral frame 106
and 106', and it is also possible to dispense with the central
magnet means and to support the vehicle merely by lateral magnet
means.
When driving the magnet vehicle along the wall surface 129, the
adhesion end portion 114 of the electromagnet 101 must be adjusted
beforehand with respect to its location. Thereafter, the magnet
vehicle is brought adjacent to the wall surface 129 of the
structural member by the use of appropriate means such as a crane,
and then by applying electric current to the electromagnet 101 and
energizing the same the magnet vehicle can be firmly supported on
the wall surface 129. The entire operation of the magnet vehicle on
the wall surface 129 is controlled by a suitable control means.
By the driving of the driving wheels 104 and 104' by means of the
driving motors 126 and 126', the magnet vehicle is advanced
straight. When it is required to alter the direction of travel,
compressed air is introduced into the air cylinder means 107
through the port 111 so that the electromagnet 101 fixed at one end
of the rod 110 may be lowered downward due to the pressure acted
upon the piston 109, to the extent that the adhesion end portion
114 abuts to the surface 129. When the electromagnet is further
depressed, the driving belts 125 and 125' are at last lifted away
from the wall surface 129. The large gear 121 mounted on the
electromagnet 101 is arranged such that it can be vertically slided
along the teeth of the spur gear 120 with its teeth engaged with
those of the spur gear. In the above case, the weight of the magnet
vehicle itself and associated devices mounted thereon is supported
only by the adhesion force of the electromagnet 101. After this,
the steering motor 116 is activated to a desired direction and the
spur gear 120 is rotated intermediary of the bevel gear 117 and 118
and shaft 119. As the large gear 121 of the electromagnet 101
cannot be rotated relative to the wall surface 129 of the
structural member owing to the fact that the vehicle is then being
supported by the adhesion end portion 114 away from the wall
surface 129, the spur gear 120 is obliged to rotate around the
periphery of the large gear 121, whereby the magnet vehicle can
alter the direction of its travel as desired. After the vehicle is
altered of its direction of travel to a desired direction, the
rotation of the vehicle is stopped by switching off the steering
motor 116, and at the same time compressed air is introduced into
the air cylinder means 107 through the port 112 and discharged from
the port 111 so that the piston 109 is lifted upward to the extent
that the adhesion end portion 114 of the electromagnet 101 is
retracted relative to the under surface of the driving belts 125
and 125'. Thereupon, said belts 125 and 125' are brought into
contact with the wall surface 129 again, and thus the magnet
vehicle is ready for advancing straight forward by the aid of the
driving motors 126 and 126'.
In one embodiment of the magnet vehicle in accordance with the
present invention, in which:
outernal dimension; width 850 mm .times. length 1050 mm .times.
height 380 mm
traveling speed; 10 meters per minute,
electrical capacity
of the center magnet; 1.2 KW DC
capacity of driving motors; 1 KW .times. 2
capacity of reduction motor; 1 KW
weight of the magnet vehicle; 370 kg
gap between the heel pieces 18 and 18' of the lateral magnet means
13 and 13' and the structural member 38; 3 mm
gap between the yoke 34 of the center magnet means 24 and the
structural member 38; 8 mm
the adhesion force exerted has been proved to be 1680 kg, and the
vehicle loaded with 50 kg could travel even on a vertical wall of
structural member 38 at will. For the purpose of utilizing this
magnet vehicle in painting operation for ships, there were
installed on the deck of a ship a control board, power source for
direct electric current, a pump and a compressor used for painting.
Further, there was mounted on the magnet vehicle a spray nozzle for
painting. With the arrangement as above, the magnet vehicle was
placed on a side wall of a ship having a radius of curvature of 10
meters, and operated by the remote control means installed on the
deck of the ship. It has proved from this experiment that the
painting according to the magnet vehicle is satisfactory and the
surface to be painted was not scarred or damaged at all.
In another embodiment of the magnet vehicle in accordance with the
present invention, the arrangement was as follows,
electrical capacity of the center magnet; 0.4 KW
capacity of the driving motors; 0.75 KW .times. 2
capacity of the steering motor; 0.4 KW
load; 80 kg
traveling speed; 15 meters per minute
gap between the adhesion end portion and the wall surface; 5 mm
The magnet vehicle arranged as above was driven along a circular
pass of 8 meter radius and it has proved that it takes three
seconds to alter the direction of travel by 90.degree.. The vehicle
could move over the wall surface at will without damaging the
same.
Although, in the aforementioned embodiments, flexible endless
V-belts or flat belts have been used as driving means, it is of
course possible to use such belt as coupled by chain or the like
with elastic element of such a reinforced plastic material.
Similarly with respect to the central magnet means, it is possible
to arrange such that a worm and a worm wheel are secured at one end
of the shaft of the electromagnet, or otherwise piston and cylinder
means are provided for moving the electromagnet upward and downward
by the aid of air pressure or oil pressure. Similarly, in place of
springs used for damping purpose in the guide pulley means, any
device having damping effect, for example, those in use of air
pressure or oil pressure can be employed.
Although in the second embodiment the magnet vehicle was operated
with the gap between the adhesion end portion and the wall surface
always constant, it is possible by adjusting the gap by use of a
gap sensor to utilize efficiently the adhesion force according to
the circumstances.
According to the magnet vehicle of the present invention, it is
possible to dispense with the platform and other devices which have
been necessary in case of conventional methods. Further, it is easy
to remove the magnet vehicle from the structural member since the
vehicle is adhered thereto only by magnetic force, and in addition
to this the magnet vehicle can be supported safely upon the
structural surface even in case that the electromagnet is not
energized. Furthermore, in accordance with the present invention,
the magnet vehicle can alter its direction of travel with high
reliability even on a considerably restricted operation surface,
without damaging same at all, and it has proved that the efficiency
of painting operation can be increased by about three times and the
expense can be reduced to about one-tenth in comparison with the
conventional arts.
Although the present invention has been described with respect to
specific details of certain embodiments thereof, it is not intended
that such details be limitations on the present invention except
insofar as set forth in the following claims.
* * * * *