U.S. patent number 3,852,601 [Application Number 05/269,668] was granted by the patent office on 1974-12-03 for scanning device for scintigraphy according to three orthogonal planes.
This patent grant is currently assigned to Ital Elettionica S.p.A.. Invention is credited to Renato Casale.
United States Patent |
3,852,601 |
Casale |
December 3, 1974 |
SCANNING DEVICE FOR SCINTIGRAPHY ACCORDING TO THREE ORTHOGONAL
PLANES
Abstract
A device for the scintigraphic scanning according to three
orthogonal planes, comprising a carrier structure for the detecting
heads including a) one horizontally located beam, longitudinally
oriented; b) two vertical columns the bases of which are provided
with rolling means suitable to cause them to longitudinally slide
along the beam, remaining guided thereon; c) two carriages provided
with rolling means capable of causing the carriages to slide
vertically each on one column, remaining guided thereon, and
provided further with a recess with rolling means capable of
supporting and causing to horizontally and transversely slide a
support rod for the detector; d) two supporting rods each
supporting a detector - each sliding in a vertical recess in one of
the carriages; e) a bracket for a first detecting head connecting
it to the end of the associated supporting rod and provided with
pre-setting means with orthogonal axes for the rotation about the
centre of gravity of the head towards all desired directions and
oriented for descending in oblique directions so that the head will
remain below the rod and displaced towards the second column; f) a
bracket for the second detecting head connecting it to the end of
the associated support rod being provided with a knuckle for
presetting a rotative position about an axis parallel to that of
the rod and for its horizontal along it so that the head will
become displaced towards the first column with respect to the rod,
and will be thus capable of aligning with the other head in both
vertical and horizontal directions.
Inventors: |
Casale; Renato (Rome,
IT) |
Assignee: |
Ital Elettionica S.p.A. (Rome,
IT)
|
Family
ID: |
11275502 |
Appl.
No.: |
05/269,668 |
Filed: |
July 7, 1972 |
Foreign Application Priority Data
|
|
|
|
|
Jul 15, 1971 [IT] |
|
|
51666/71 |
|
Current U.S.
Class: |
250/366;
250/363.08 |
Current CPC
Class: |
G01T
1/166 (20130101) |
Current International
Class: |
G01T
1/00 (20060101); G01T 1/166 (20060101); G01t
001/20 () |
Field of
Search: |
;250/50,60,61.5,71.5S,366,369,394,360 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Borchelt; Archie R.
Attorney, Agent or Firm: Browne, Beveridge, DeGrandi &
Kline
Claims
Having thus described the present invention, what is claimed
is:
1. In a device for scintographic scanning according to three
orthogonal planes employing two detecting heads arranged for
adjustment along, above and transversely of a longitudinal and
horizontal beam position the improvement comprising;
a beam horizontally disposed in said position,
two vertical column structures including chain means for moving the
same along said beam;
two recording devices;
frame support means mounted fixedly on said beam including
longitudinally extending carriage guide means and transverse guide
means;
a horizontally disposed recording surface mounted on said frame
parallel to said guide means;
chain drive means for moving said carriage along said horizontally
extending and transverse guide means respectively;
two column carriages mounted for vertical movement along said
columns, respectively, having means for moving the same vertically
along the columns;
each last said carriage including rod means for supporting a
detector head for horizontal transverse scanning motion in respect
to the support carriage, a first said rod means in one column
including a bracket on an outer end thereof for supporting a
detecting head in rotatable movement about an inclined axis, the
bracket being rotable about the first rod means;
a detecting head rotatably mounted on said first rod means at an
outer end of said bracket for varying displacement beneath first
said rod means and toward the other column as the bracket
rotates;
a second said rod means in the other said column including a
rotatable knuckle at an other end thereof comprising means for
supporting a second detecting head beneath said second rod
means;
a second said detecting means mounted on said knuckle for rotation
about the axis of said second rod means;
said first and second rod means being adjustable vertically and
independently of each other by chain means extending vertically in
said columns and horizontally along said beam by further chain
drive means operative to move said columns therealong, said
detecting heads being rotatively adjustable to detect in like
directions vertically and horizontally, said bracket inclinable
relative to said first rod means to align said detecting heads
horizontally or vertically;
means operating said chain means for moving the columns and said
chain drive means being selectively operable for effecting desired
three plane scanning motions; and
means coupling each recording head drive means to effect motion
thereof corresponding to scanning motion of said detecting
head.
2. A scintographic scanning device according to claim 1, said chain
drive means for driving the detecting heads vertically comprising
first and second primary chain drives, one for each column and said
chain drive means for driving the detecting heads transversely of
said beam comprising first and second auxiliary chain drives
extending along said rod means, respectively coupable one to one
said primary chain drive and one to the other said primary chain
drive, said primary chain drives extending parallel to each other
at least in said columns, being aligned therein by gear ring pairs
on the same axes within the columns, respectively.
3. A scintographic scanning device according to claim 2 said
primary chain drives extending in said columns about two gear ring
pairs on the same axis provided at the lower end of each column and
one gear ring pair on the same axis at the upper end of each column
and including electromagnetic means for coupling primary and
secondary chain drive means selectably and separately for selective
and separate driving of the detecting heads.
4. A scintographic scanning drive according to claim 3, said
primary chain drives extending over gear rings on the same axis
respectively driving a further auxiliary chain coupled to a further
carriage over a gear ring on said same axis and in driving relation
to chain means driving said recording devices in correspondence to
motions of said detecting heads.
5. A scintographic scanning device according to claim 4, said
recording devices comprising optical beam projectors faced toward
respective photographic plates for simultaneous photographic
recording of the three orthogonal plane scans.
6. A scintographic scanning device according to claim 4 wherein
said chain means driving said recording devices are coupled to said
primary chain drives by motion-reduction means for changing the
scale of recording relative to the scale of scanning in the three
orthogonal planes.
Description
The present invention relates to a scintigraphic scanning device
according to three possible orthogonal planes, for detecting the
distribution of the radioisotopes in the bodies of patients, with a
scanning field which can also extend to the entire body.
This scanning device affords, with respect to the known similar
devices, the advantages of having two detecting heads, two systems
for recordal on paper and two photographic recordal systems which
can be utilized in various modes in order to comply with the most
different conditions of use. Furthermore the two detecting heads
can operate on the same focal axis with opposite senses either
according to a horizontal scanning plane, reaching the dimensions
of the entire body, or according to a vertical scanning plane,
establishing on the recording devices separate and superposed
scintigraphies of the radio-activity detected by the two heads. The
heads can also operate side-by-side in longitudinal and transverse
senses according to a horizontal scanning plane; the heads can also
operate simultaneously: the first head according to a horizontal,
lateral or frontal plane, and the second head according to a
horizontal or lateral plane at right angles with respect to the
plane whereon operates the first head, determining simultaneously
the scint-igraphies of the two projections on each pair of
recording devices.
Another advantage with respect to the known systems is that
notwithstanding the plurality of the possible scanning planes and
of the modes of movement of the detecting heads in these planes,
the movement members connecting the detecting heads, the heads
writing on paper and the projectors of the recording devices are
entirely mechanical members. This fact allows the heads to be
predisposed on the areas to be scanned and to be moved
simultaneously within the pre-selected areas by manually operated
movements with no danger for the patient, so as to dispense with
the cumbersome and complicated safety systems.
Other advantages with respect to the known systems with a
mechanical coupling, consist in the possible simultaneous
observation of the patient and of the scintigraphies on paper,
during the scanning operation, and the possibility of effecting the
scintigraphies both in normal size and in reduced size.
In order to achieve the above disclosed advantages, a carrier
structure for the detecting heads comprises: a) a beam,
horizontally and longitudinally located which rests on the floor on
suitable supports; b) two vertical columns, the bases of which are
provided with rolling means suitable to allow the columns to slide
longitudinally along the beam keeping the columns steadily vertical
while moving therealong thereon; c) two carriages provided with
rolling means suitable to allow the carriages to slide vertically
each on one column, keeping the carriages uniformly guided
therealong and having also a recess with rolling means suitable to
support and to allow the horizontal sliding of a rod supporting the
detector, with a transverse direction of movement, i.e. horizontal
and in a direction at right angles to the direction of movement of
the column along the beam; d) two supporting rods for the detectors
each sliding in the associated recess in its carriage; e) a bracket
connecting the first detecting rod to the end of the associated
supporting head provided with two presettable articulated couplings
with axes at right angles to one another for the rotation about the
centre of gravity of the head toward all directions at will; which
bracket is oriented in oblique descending direction, in order to
locate the head entirely below the rod while being displaced toward
the second column; f) a bracket or arm connecting the second
detecting head to the end of the associated supporting rod,
provided with an articulated coupling for the presetting its
rotation about the centre of gravity of the head about an axis
parallel to that of the rod and for its movement along that axis;
which bracket is horizontally oriented so that the head will be
displaced towards the first column with respect to the rod, and can
be thus aligned with the other head in both vertical and transverse
directions.
In order to achieve these advantages a recording unit for the
scintigraphic scanning comprises: a) a frame, rigidly connected to
the beam of the carrier beam, provided with two longitudinal guides
one above the other whereon there is mounted a horizontal plane for
the recording on paper of two scintigraphies, side-by-side located
in a transverse sense; b) a carriage, movable with respect to the
carriage on the two guides; c) a guide horizontally supported by
the carriage in a direction transverse to the plane of recording on
paper; d) a carriage sliding on the transverse guide and carrying
both heads for the recording paper; d) a double photographic
recorder with films located in a vertical plane, parallel to the
direction of the two guides on which moves the first named
carriage, in the dark chamber of said photographic detector
extending through a light tight passage, two vertical parallel
guides, parallel also to the plane of the film, and cantilever
supported by the carriage; f) two carriages sliding on the two
vertical guides of the photographic recorder, one of said last
cited carriages supporting the photogrpahic recorder, and the other
the counterweight therefor; g) a metal tape drive or the like
connecting the two carriages of the photographic recorder and the
carriage of the recorder on paper so that the movement of the
projector and of its counterweight will occur towards opposite
directions, in order to prevent the tape drive from imparting a
lateral thrust to the carriage of recordal on paper.
In order to attain the above indicated advantages, this invention,
utilizes as driving means for the detecting heads and the recording
devices on paper, of a drive system including: a) two chains which
will be called: line feed of the detecting heads and scanning
primary chain of the detecting heads, respectively, each passing
around two gear rings the shafts of which are rigid with the beam
at opposite ends thereof, then around three gear rings the shafts
of which are rigid with the first column, and around three other
gear rings the shafts of which are rigid with second column, so
located that the portions of chain comprised between one gear ring,
the shaft of which is rigid with the beam, and one gear ring the
shaft of which is rigid with the one column and between gear rings
the shafts of which are rigid with each of the columns, will be
parallel to the direction of movement of the columns on the beam,
whereby the total length of each chain will be constant when the
column moves along the beam, and that portion of each chain
comprised between gear rings the shafts of which are rigid with
each of the two columns, will be parallel to the direction of the
movement of the carriages on the columns; b) two chains which will
be called: line feed of the recording devices and scanning primary
chain for the recording devices, respectively; the first chain
passes around about two gear rings with shafts rigid with the frame
and with at least one portion of the path parallel to the direction
of the movement of the carriage for the recording group with
respect to the frame, and in that portion the chain is connected to
the carriage, while the second chain passes around about two gear
rings the shafts of which are rigid to the frame, and about three
gear rings the shafts of which are rigid with the carriage, so that
the portions of chain comprised between one gear ring the shaft of
which is rigid with the frame and a gear ring the shaft of which is
rigid with the carriage, will be parallel to the movement of the
carriage with respect to the frame, whereby the total length of the
path of the chain will be constant when the carriage moves with
respect to the frame, and one portion comprised between two gear
rings the shafts of which are rigid with the carriage will result
almost vertical; c) two devices, the first of which connects
directly, or with a scaled-down motion one of the gear rings the
shaft of which if fixed to the beam and around which passes the
feed line chain for the detecting heads with a gear ring, the shaft
of which is rigid with the frame around which passes the feed line
for the recording devices, and the second of which makes a similar
connection for two gear rings about which pass the two primary
scanning chains; d) two secondary scanning chains for the detecting
heads, which pass: the first chain about four gear rings the shafts
of which are rigid with the carriage of the first column, with such
a path that one portion will result parallel to the movement of the
carriage with respect to the column, and that one portion will be
disposed parallel to the movement of the rod with respect to the
carriage, and the second chain is similarly applied to the carriage
of the second column, both secondary chains being connected to the
rods at a point in the portion parallel to their motion with
respect to the carriages; e) a secondary scanning chain for the
recording devices passing around four gear rings the shafts of
which are rigid with the carriage of the recording group with such
a path that one portion will be parallel to the path of a
substantially vertical portion of the primary scanning chain of the
recording devices, which portion will be parallel to the movement
of the carriage guiding the heads recording on paper; the secondary
scanning chain for the recording devices being connected directly
to the primary chain in a point of the portion where the two chains
have parallel paths and being connected to the carriage driving the
heads for recording on paper at a point where the chain has its
path parallel to the carriage notion with the interposition of a
device allowing an adjustable clearance for removing the
scallopping of recording and comprising a second auxiliary
carriage; f) a group of eight electromagnetic clutches for
selectively governing the feed line notion directions for the
selection of the scanning planes and for positioning the scanning
areas, two of which allow the feed line chain for the detecting
head to be fixed to each of the two columns at a pre-selectable
point along one of the portions parallel to the movement of the
columns along the beam, two other of said clutches allowing said
chain to be fixed to each of the two carriages at a point
pre-settable along one of the portions parallel to the movements of
the carriages along the columns, other four clutches locking the
columns to the beam and the carriages to the column; so that the
feed line movement of each detecting head can be selected
independently in longitudinal direction with the movement of the
columns along the beam, or in vertical direction with the movement
of the carriages along the columns while on the recording devices
it follows always the direction of the carriage in the frame; g) a
group of four electromagnetic clutches for pre-setting the
connection of the secondary scanning chains, for selecting the
scanning plane of the first detecting head and for positioning the
scanning areas, allowing one to fix the secondary scanning chains
to the carriage or to the primary chain at a point pre-selectable
along the portion wherein their path is parallel to the movement of
the carriage, by operating said clutches, together with the
clutches as already mentioned, for locking the carriages to the
columns, the scanning movement of the first detecting head can
occur in vertical direction, moving the carriage along the column,
or in transverse direction, by moving the rod with respect to the
carriage by means of the secondary chain, while the second
detecting head and the recording head on paper will be always
transversely moved through the associated secondary chains, and the
projectors of the photographic recorders will be always vertically
moved through the further intervention of the tape drive; h) a
motor with a gear box which drives, through two electromagnetic
clutches, the same rotational movements to both a gear ring the
shaft of which is rigid to the beam and around which passes the
feed line chain for the detecting heads, and to a similar gear ring
about which passes the primary scanning chain of said head; when
the clutch for the motor-scanning chain is actuated the feed line
chain is locked by the pre-setting clutches or by a suitable clutch
while the motor-feed line chain clutch is free, the motor imparts
the scanning movements to both the detecting heads and to the
recording devices; when both the clutches between the motor and the
chains are actuated and the locking device for the feed line is
released, the motor which moves to an equal extent the two chains
imparts the feed line movements while preventing relative movement
between the two chains, no scanning movement will occur; when all
three electromagnetic clutches are released, the heads can be
manually moved for searching the hot point, or for positioning.
The scintigraphic scanning device according to three planes as
described can obviously be embodied in reduced scale, without the
second detecting head with its associated supporting column and
without the second pair of recording devices or without
photographic recorders, without departing from the scope of the
present industrial privilege.
For a more complete disclosure of this invention, reference will be
made hereinafter to the attached drawings where:
FIG. 1 shows a perspective view of the system;
FIG. 2 shows the second column without the covering members and in
partially exploded view of the carriage and of the chains;
FIG. 3 shows the recording unit with part of the structure removed
and part in exploded view for showing the motor reducer, the scale
reducer, the chains and the carriage.
FIG. 4 shows the details of the photographic recording portion of
the unit of FIG. 3.
FIG. 5 shows a diagram of the driving elements for the detecting
heads and for the recording devices.
With reference to FIG. 1, there has been shown a horizontal beam 1
supported by four feet 2. On the beam 1 slides a base 3 supporting
a column, concealed by the cover 4 and a second base 5 supporting a
second column concealed by the cover 6. The bases 3 and 5 are
provided with rolling means, not shown for sake of simplicity
suitable to cause said bases to slide along the beam 1, maintaining
said bases steadily guided thereon, i.e., in fixed orientation
while moving smoothly therethrough. The structure of the like
columns is shown in FIG. 2, wherein is shown the base 5 and the
column proper 7 the structure of the two columns being similar.
Along each of the two columns slides vertically a carriage, which
in FIG. 1 is covered by the fairings 4 and 6, the second column
carriage 8, being shown in FIG. 2. Vertical sliding of the carriage
along the column is obtained by suitable rolling means capable of
causing the carriage to slide vertically maintaining it steadily
guided in a well known manner on the column the illustration of
which has been omitted for sake of simplicity. The weight of the
carriage 8 and elements attached thereto is balanced by a suitable
counter-weight, contained in the column 7 supported by chains 9 and
10 on pinions 11 and 12. The carriage 8 is provided in its lower
part with a recess 13 within which axially slides a rod 14 guided
and supported by suitable rolling means, not shown for sake of
simplicity. The carriage of the first column is similar to that of
the second column, shown in FIG. 2, with the difference that the
recess for the rod is in the upper part of the carriage instead of
being in its lower part, whereby as can be seen in FIG. 1 that rod
15 at parity of heights of the carriages, will be at a lever higher
than rod 14. This make possible translations of the columns at
right angles to the beam, of the carriages at right angles to the
axes of the columns, and the rods at right angles to the carriages,
whereby the detecting heads supported on the rods can carry out the
scanning in three orthogonal planes namely horizontal, frontal
vertical or lateral vertical.
At the end of the rod 15 is connected a bracket 16 supporting the
detecting head 17. This bracket is constructed to rotate about the
inclined axis A-A' passing through the center of gravity of the
head 14, which head in turn can rotate with respect to the bracket
16 about the axis B-B' which also passes through its center of
gravity. By means of said rotations about two axes at right angles
the head 17 can be rotated about its centre of gravity towards any
wanted direction, and to be fixed in said direction by frictional
means or suitable brakes not illustrated for simplicity. At the end
of the rod 14 there is connected a bracket 18, horizontally
mounted, which supports the detecting head 19, rotatable about the
axis C-C' which passes through its centre of gravity, by means of
the slidable knuckle 20. This allows the head 19 to both rotate
about the axis C-C' and sliding along that axis. A brake, not shown
in the figure may be provided in order to lock the knuckle 20. The
direction and the sense wherein each of the two detecting heads is
sensitive to radiation, has been shown for the head 17 by the arrow
D and for the head 19 by the arrow E,. FIG. 1 shows a
predisposition of the heads suitable to the simultaneous scanning
of two co-planar areas horizontal and at right angles with respect
to D and E, located side-by-side in the longitudinal direction of
the beam, with equal and simultaneous movements of the two heads.
The location and the dimensions of the brackets 16 and 18,
particularly and of the various elements generally, is such that as
shown by the FIG. 1, the two heads can also be located side by side
causing the axis B-B' to correspond with the axis C-C' and
maintaining unaltered the direction and the sense of the arrows D
and E, suitable to the simultaneous scanning of two horizontal
areas located side by side in transverse direction. If a rotation
through 180.degree. is effected about the axis C-C', of the head 19
with respect to its position as shown in FIG. 1, lowering suitably
the carriage 8 of the second column 7, the arrows D and E can be
aligned on the same vertical straightline, with opposite and
convergent senses allowing thus the scanning of the same horizontal
area with a sensitivity doubled with respect to that of a single
head. If also the two heads will be rotated through 90.degree. with
respect to the position shown in FIG. 1, about the axes B-B' and
C-C', the arrows D and E can be aligned along a single horizontal
straightline, in transverse direction, with opposite and convergent
senses, allowing the scanning of a lateral vertical plane with a
sensitivity doubled with respect to that of a single head. If the
bracket will be rotated with respect to the position of FIG. 1,
about the axis A-A', downwards until carrying the axis B-B' on a
vertical plane, frontally located along the direction of the beam
1, the head 17 will be rotated about the axis B-B' until the vector
D will be located horizontally, perpendicular to the frontal plane
and turned towards the person who observes the FIG. 1, and finally
the head 19 will be moved along the axis C-C' towards the person
who observes the FIG. 1, and the head 17 through a suitable
downwards displacement of the carriage which supports the same head
17, will be located in a position suitable for scanning a frontal
plane, while simultaneously the head 19 can scan a horizontal
plane.
FIG. 3 shows the frame 20 of the recording unit, rigidly connected
to two beam 1, and on said frame is located the plane 21 for the
simultaneous recordings on paper. Fixed to the frame in
longitudinal direction are the cylindrical guide 22 and the square
section guide 23 along which slides the carriage 24 (which in FIG.
3 is partially removed and in exploded view in order to permit the
driving members to be seen) by means of the three sliding supports
25, 26 and 27. The carriage 24 supports the cross-guide 28 on which
slides the carriage 29 guiding and driving the writing heads 30 and
31. FIG. 4 shows the double photographic recording device with the
dark chamber 32 within which extend the vertical guides 33 and 34
cantilever supported by the carriage 24 through a light tight
passage allowing said guides to move longitudinally with the
carriage. Along the guide 33 slides the carriage 35 supporting the
two projectors 36 and 37 which are faced to the photographic plates
38 and 39 which are shown in FIG. 4 as removed and contained in
their associated plate-carriers. Along the guide 34 slides the
counter-weight 40 which is moved oppositely to the carraige 35 by
the steel tape 41 which is extended about the pulleys 42, 43, 44
and 45 and which is operated in turn by the carriage 29 controlling
the writing heads. The counter-weight prevents the tape 41 from
imparting a static lateral thrust to the carraige 29.
The FIG. 5 shows a diagram of the driving elements for the
detecting heads and the recording devices consisting of a chain
system operated by a single gearbox-motor unit and of
electromagnetic clutches in order to connect them according to the
exigencies.
The same elements of the diagram corresponds to those shown in
FIGS. 2 and 3, denoted by the same numeral references.
In FIG. 5 there is shown the primary scanning chain 46 for the
detecting heads passed around ten gear rings numbered 47 to 56, the
gear rings 47, 48, 49 and 56 having their axes fixed on the unit
consisting of the recording device frame and of the beam, while the
gear rings 50, 51 and 52 have their axes fixed to the first column,
and the gear rings 53, 54 and 55 fixed to the second column. During
the movement of the columns along the beam, the extent of the path
of the chain 46 does not change as the three portions comprised
between the gear rings 49 and 50, 52 and 53, 55 and 56, are
parallel to the movement of the columns along the beam. FIG. 5
shows also the feed line chain 57 for the detecting heads, having a
path similar to that as previously described and passed about ten
gear rings numbered 58 to 67. Also, the primary scanning chain 68
for the recording devices is shown, extended about the five gear
rings numbered 69 to 73, the gear rings 69 and 73 having their
shafts fixed to the frame for the recording devices, while the gear
rings 70, 71 and 72 have their shafts fixed to the carriage of the
recording device. The portions of the chains comprised between the
gear rings 73 and 72 and between the gear rings 70 and 69 are
parallel to the direction of movement of the carraige on the frame,
causing a constant length of path of the chain 68 when the carriage
slides along the frame. In FIG. 5, also the feed line chain 74 for
the recording devices is shown, passed about the gear rings 75 and
76, the shafts of which are fixed to the frame. The chain 74 is
connected to the carriage 24 is a portion of the path parallel to
the movement of the carriage along the freme. The gear ring 48 is
connected to the gear ring 69 by means of interconnector group 77
containing two electromagnetic clutches and four gears whereby it
is possible to select a direct coupling or a reduction of speed
when passing from the gear ring 48 to the gear ring 69, for
instance down from 4 to 1 in order to obtain a corresponding
reduction in the recording scale. A similar interconnector group 78
connects the gear ring 59 to the gear ring 75. The group 78 is
shown in FIG. 3 in exploded view in order to show the gear rings
behind it. FIG. 5 shows also the secondary scanning chain 79 of the
first carriage extended about the four gear rings 80 to 83, all
these gear rings having their shafts rigid with the carriage of the
first column. The portion of the chain 79 comprised between the
gear ring 80 and 81 is parallel to the portion of the primary
scanning chain 46 comprised between the gear rings 51 and 52 and
the portion comprised between the gear rings 81 and 82 is parallel
to the movement of the rod 15 supporting the head 17, to which it
is connected. Likewise, the secondary scanning chain 84 for the
second carriage extended about the four gear rings 85 to 88 is
connected to the rod 14 carrying head 19. FIG. 5 shows also a
secondary chain 89 for the recording devices, which extends about
the four rings 90 to 93, all these gear rings having their shafts
rigid with the carriage 24 for the recording devices. The chain 89
has a portion comprised between the gear rings 90 and 93 parallel
to the portion of the primary chain 68 comprised between the gear
rings 70 and 71 and connected thereto. This chain has also a
portion comprised between the gear rings 90 and 91 parallel to the
movement of the carriage 29 controlling the writing heads and is
connected thereto by means of the auxiliary carriage 94. Between
the auxiliary carriage 94 and the carriage 95 there is an
adjustable clearance for eliminating the scalloping of the
recording medium. FIG. 5 shows also two electromagnetic brakes 95
and 96 locking the gear rings 61 and 64 to the columns, fixing the
feed line chain 57 to the first column and to the second column,
respectively, two auxiliary columns 97 and 98 pivoted on the
carriages and in mesh with the feed line chain 57, two brakes 99
and 100 locking on the carriages the gear rings 97 and 98 fixing
the feedline chain to the first carriage and to the second carriage
respectively, the electromagnetic brakes 101 and 102 which lock the
two columns on the beam and 103 and 104 locking the carriages to
the columns. By suitably presetting said brakes either in their
locked or released positions, the feed line movement can be
selected for the detecting heads, as either a movement of the
columns with respect to the beam, or a movement of the carriages
with respect to the columns; while on the recording devices the
feed line movement corresponds always to that of the carriage with
respect to the frame, and further when the brakes are released, the
heads can be positioned on the scanning areas. FIG. 5 shows also
the auxiliary carriages 105 and 106 sliding on vertical guides
fixed to the carriage, to said auxiliary carriages being fixed the
secondary scanning chains 79 and 84. On said auxiliary carriages
are pivoted the auxiliary scanning gear rings 107 and 1o8 engaged
with the primary scanning chain and it is possible to lock said
gear rings on the carriages by the electromagnetic brakes 109 and
110, which thus will lock the primary scanning chain 46 to the
secondary chains 79 and 84. The carriages 105 and 106 can be locked
to the column carriages by the brakes 111 and 112. By predisposing
suitably the brakes 103, 109 and 111, the scanning movement of the
first head 17 can be selected as either movement of the carriage
with respect to the column, or movement of the rod with respect to
the carriage, and also, when the brakes are released, the head can
be positioned on the scanning areas. Similar possibilities exist
for the second head, by presetting the brakes 104, 110 and 112,
although practically only the positioning of head 19 will be
utilized, utilizing as scanning movement only that of the rod with
respect to the carriage. The FIG. 5 shows also a gearbox-motor unit
113 which transmits the same movements to the gear ring 47 and
consequently to the feed line chain 46 through the electromagnetic
clutch 114 and to the gear ring 58 and consequently to the primary
scanning chain 57 through the electromagnetic clutch 115. The
electromagnetic brake 116 allows the gear ring 49 to be locked and
thus the feed line gear will be locked. When the clutch 115 is
inserted, the clutch 114 is released and the brake 116 is locked
the motor transmits the scanning movements to the head; when both
the clutches 114 and 115 are actuated and the brake 116 is
released, the feed line movement will be obtained with non scanning
movement; when both clutches and the brake are released, it is
possible to move manually the heads for positioning them, although
remaining connected their position relative to that of the
recording devices with respect to the heads.
The present invention has been illustrated and described in one
preferred embodiment, it being however understood that variations
might be practically adopted without departing from the intended
scope of the invention except as limited by the claims.
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