April 1966 E. A. LABUS ETAL 3,244,883
X-RAY TUBESTAND Filed Sept. 12, 1963 I N VEN TOR. EDWARD A. LABUS Y ROBERT J. MUELLER ATTORNEY United States Patent 3,244,883 X-RAY TUBESTAND 7 Edward A. Lahus, Milwaukee, and Robert J. Mueller,
Brookfield, Wis., assignors to General Electric Company, a corporation of New York Filed Sept. 12, 1963, Ser. No. 308,405
7 Claims. (ill. 250-91) This invention relates to a tubestand for positioning an X-ray tube with respect to an X-ray table.
Among the objects of the invention are to provide an X-ray tubestand that is supported on the room structure independently of the X-ray table and away from it so that the operator may move around the table without interference by the stand.
Another object is to remove the lower guide track of such a tubestand from its customary position immediately adjacent the X-ray table, where the operator frequently tripped over it.
Another object is to support the X-ray tube on a telescoping extensible and contractible arm that facilitates transverse movement of the tube over the active width of the X-ray table and which permits the tube to be placed in a parked position where it does not interfere with activity around the table. An adjunct of this object is to 3,244,883 Patented Apr. 5, 1966 tubestand column and the criss-cross stabilizing cables therefor; I
FIGURE 5 is a schematic showingof the counter balancing means for the X-ray tube support; and
FIGURE 6 shows the details of the lower guide rollers and track as viewed in the direction of the arrows 6-6 in FIGURE 5.
Referring to FIGURE 1, the tubestand comprises an upright member. 9 including a pair ofvertical columns 10 and 11 which extend between the upperguide rail assembly 12 and a lowerguide rail assembly 13. Theupright member 9 has wheels at its upper and lower extremities which cooperate with the guide rails in such manner as to allow the upright to be translated therealong unitarily and in parallelism with the wall of the room and an X-ray table 14. The wheels are typified by a provide a laterally telescoping tube support arm whose 7 sections are adapted to move equidistantly and in unison for improved simplicity, appearance and sturdiness as compared with other telescoping supports of the prior art in which one section moved to its limit before the next section began to move. Other important features of the instant telescoping support are that its sections may be locked by locking only one section, and that it is readily adaptable of being motorized.
A further object of this invention is to provide a tubestand that facilitates directing the X-ray beam laterally and frontally through the patient, while the X-ray table is horizontal or angulated vertically, without the requirement of swinging the tube support arm parallel to the table as is necessary in prior designs. An incident to this feature is that the lower guide track for the longitudinally translatable upright member of the stand need only approximate the length of the X-ray table since the column does not have to go way beyond the table in order to direct the beam laterally through the patents upper or lower extremities.
A further object is to provide a tubestand that has a small wheel base and takes up less floor space, this being facilitated in part by use of criss-cross cables to stabilize the upright member when it is at rest and in motion.
.Yet another object is to provide a support that allows an X-ray tube to be positioned above or below the X-ray table top.
Achievement of these and other more specific objects will appear from time to time throughout the course of the specification.
A more detailed description of a preferred embodiment of the invention will now be set forth in conjunction with the drawings in which:
FIGURE 1 is a perspective view of the new tubestand installation accompanied by an X-ray table body which is shown in outline;
FIGURE 2 is a sectional view of the new telescoping tube support arm taken normal to a vertical plane whose edge may be viewed in the direction of thearrows 22 in FIGURE 1;
FIGURE 3 is a side view of the telescoping tube support arm which is partly in section as taken on the line 3-3 in FIGURE 2, some parts being omitted;
FIGURE 4 is a schematic representation of the vertical showing of the lower wheels and track in FIGURE 6.
Acarriage 15 that is adapted for Vertical movement oncolumns 10, 11 has extending from its front an extensible and 'contractible X-ray tube support arm assembly that is designated generally byreference numeral 16. Atthe end ofarm 16 theX-ray tube casing 17 is supported in such manner that it may be turned on the axis of thearm 16 and on its own longitudinal axis, thus enabling the X ray beam to be directed downwardly toward the table top or laterally and longitudinally of X-ray table 14. Attached to-the bottom ofX-ray tube casing 17 is a beam defining cone orcollimator assembly 18 which may be conventional.
In FIGURE 1,collimator 18 is disposed to direct the beam of X-rays in a vertical direction toward the top of X-ray table 14. It will be understood that X-ray table 14 is typically adapted to be angulated to either vertical position in which case thetube casing 17 would be rotated on the axis ofarm 16 in an appropriate direction for aiming the X-ray beam so that it would penetrate the table top and record an X-ray image on a film which is usually in a cassette inside the table.
Occasions arise when the radiologist desires to take a lateral radiograph of a patient who is lying on the table top while the table is in an essentially horizontal position or while the patient is upright as a result of tilting the table to one of its vertical positions. In such instances, theX-ray tube casing 17 is rotated 90 degrees more or less so that the beam emerges out of bottom of the collimator which is to its left sideas it appears in FIGURE 3. To permit rotation of the X-ray tube casing, it is journaled on four equiangularly spacedbearing pads 19 in an apby actuation of ahandle 21 whose associated mechanism is not shown in detail because it can be readily devised by a skilled mechanical designer. In FIGURE 3, it may also be seen that the X-ray tube casing is adapted for being rotated on the longitudinal axis of thetelescoping arm assembly 16. This involves making a shaft and bearing connection betweenbracket 29 and theinnermost section 25 oftelescoping arm 16. The shaft and bearing are not shown but it may be seen that thebracket 20 andsection 25 abut each other through the agency ofcircular bearing plates 22 and 23 which may be clamped and unclamped by actuation of acam operating lever 24.
In FIGURE 1, the conventional electric power cables extending from theX-ray tube casing 17 to thepower supply enclosure 26 have been omitted for the sake of clarity. The means for draping and handling the cables have also been omitted. The cable is admitted to thecasing 17 via asocket 53, see FIGURE 3.
The telescoping X-ray tubesupport arm assembly 16 will now be described primarily in connection with FIG-URES 2 and 3. Thearm assembly 16 extends from the verticallymovable carriage 15. The carriage is mounted on tracks that are on the back of columns '10, 11 but these and their rollers are not shown since they are a matter of designers choice. In FIGURE 3 it will be observed that, in this example, thetelescoping arm assembly 16 comprises four tubular sections, the outer one 55 of which is the largest and is fixed oncarriage 15. The others aremovable sections 45, 35 and 25 which are adapted to roll or slide telescopically within each other and to reach their most contracted position within fixedmember 55. The interconnection of the sections is such that if any one of them is urged in such direction as to contract the arm assembly, each section will move an equal distance concurrently, after which they will all come to rest in their home nesting position withinfixed section 55. All movable sections also move equal distances concurrently when the arm assembly is extended. a I
The various telescoping arm sections, in this example, are steel tubes of square cross-section. They may be adapted to glide within each other by any suitable means such as on rollers. In this embodiment, the largestmovable section 45 hassteel blocks 27, 28, and 29 welded to it. Each block has a shaft on which there is journaled a ball hearing orroller 30. Ifsection 45 is Withdrawn fromfixed section 55,roller 30 and the rollers that are carried onblocks 23 and 29, will roll on the internal surface of bothsection 55 and a bearing surface created by anangle rail 31 which is welded to the interior ofsection 55. It will be seen that the rollers on supportingblocks 27 and 2&5 accept th vertical stress due to the cantilever loading imposed by the X-ray tube casing and collimator while the other guide rail associated withblock 29 guides and stabilizes the telescoping assembly against lateral loads. It will be seen by inspection of FIGURE 2 that thesections 25 and 35 are also provided with correspond-- ing pairs of rollers that rotate on horizontal axes and another roller on a vertical axis which cooperates with guide tracks that are fixed on the next largest section for the purpose of supporting and guiding each section with respect to the other. Each guide rail like 31, is almost coextensive in length with the telescoping section to which it is attached. In FIGURE 3, the guide rollers and rails are omitted to facilitate explanation and eliminate the obscurity that would result from superposition of the parts in the drawing.
As stated earlier, thevarious telescoping sections 25, 35, and 45 are adapted to move in unison and equidistantly when a force is applied to any one of them for the purpose of contracting or extending thetube support arm 16. To achieve this end, the various sections are interconnected with chain and rack and pinion drives.Section 35 carries ashaft 33 which is journaled in abearing 34 that is fixed onsection 35.Shaft 33 is provided at one end with asprocket 36 over which a closed loop of chain 37 runs. As seen in FIGURE 3',sprocket 36 has a mating idler sprocket 39 which is also journaled in a bearing like 34 that is fixed insection 35 and near the outside end thereof.
The chain loop 37 is closed by anchoring its ends to a fixedblock 46 on the smallestcentral section 25; Also onshaft 33 is apinion 41 that engages with-agear rack 42 thatis fixed on the inside ofsection 45 by screws or other suitable means.
The driving interconnection between the other sections is similar. To elaborate, thesection 45 supports a bearing 43 in which ashaft 44 is jour'naled. At one" end of th shaft there is asprocket 46 with achain 47 running over it, the free ends of the chain being connected to a block 43 that is carried by movable section 35.- Shaft 44- a'lso carriesapinion 49 that meets with arack 50, the latter being permanently attached to the interior of fixedsection 55. Thechain 47 also runs on anidle sprocket 51 which is journaled in a Wall ofsection 45.
An understanding of howsections 25, 35, and 45 are compelled to move in unison when any one of them is urged axially, may be gained by focusing attention onshaft 33 and its affiliated parts. In reference to FIGURE 2, assume that a force is applied tocentral section 25 such as to withdraw it lengthwise from the plane of the paper. Upon this event, chain 37 will translate and it will causesprocket 36 to rotate. Were it not forshaft 33, no relative movement would take place betweensections 25 and 35. However,pinion 41 onshaft 33, as a result of its interaction withrack 42, causesshaft 33 to translate andurge section 35 in the same direction assection 25 is moving.
Attention is now focused onshaft 44 and its associated parts to discover howsection 45 is moved. Whensection 35 commences movement, it carries with itchain anchor block 48 which causes chain 4-7 to translate and rotatesprocket 46, which rotates withshaft 44 andpinion 49. The interaction betweenpinion 49 and stationary rack on fixed section then causessection 45 to translate at the same rate and distance assections 25 and 35.
A concomitant of thetelescoping section 25, 35, and 45 moving equal distances and in unison when one of them is moved, is that the locking of any one of the sections locks the others against relative movement with respect to each other. Thus, only a single lock is required in the instant design as compared with prior art telescoping supports in which each section must be locked individually. In the instant case, an electromagnetic lock is used. It consists ofa stator housing 69 which has an internal winding, not shown, that produces a magnetic field when energized. Extending through housing 65 is ashaft 61 that carries at its lower end abrake disc 62 which is attrace abl into frictional engagement with the stator frame when energized. This stops rotation of shaft el. At the top end ofshaft 61, as viewed in FIGURE 2, there is attached asprocket 63 over which achain 64 runs. The ends of the chain are connected with an anchor block 66 that is hired on and moves withtelescoping section 45. When the brake is deenergized, movement of the telescoping sections merely translates the chain and causesshaft 61 to rotate freely. When the brake is energized,disc 62 adheres and prevents rotation ofshaft 61 which in turn prohibitschain 63 from translating and causes holding ofsection 45. By virtue of the interconnecting driving mechanism described above, the holding force is transmitted to the various sections and they are all prevented from moving.
How the telescoping assembly may be motorized should now be apparent. It is only necessary to substitute a motor for the brake assembly in whichcase shaft 61 may be. turned bi-directionally for transmitting a driving force through a chain like 64. If a brake and motorized assembly are both used, the motor unit may be mounted on the side of theoutside section 55 as viewed in FIGURE 2. Because the outside fixedsection 55 is fixed and extends through the front ofvertical carriage 15, a drive motor may be located similarly to thebrake assembly 60 in the back of the vertical carriage so that it is not seen from the front. It may also be remarked, incidentally, that necessary clearance between the wall of'the room and the tubestand is held to a minimum by reason of the telescoping sections not extending backwardly beyond col umns 10, 11 when the sections are retracted.
An important feature of the invention resides in the manner in which theupright 9 is maintained in true vertical attitude when it is being translated along guide tracks 12, 13. By reference to FIGURE 4, one may see thatcolumns 16 and 11 are joined at their lower ends by a connectingmember 70 which is equipped withwheels 71 that run on a floor mountedtrack 13. The upper ends ofcolumns 10 and 11 are joined by amember 73 having characteristics similar to member 7a at the bottom. There is a pair of groovedpulleys 74 and 75 on bottom member 70'. Another pair ofpulleys 76 and 77 are journaled for rotation on thetop member 73. A stabilizingcable 78 originates at ananchor point 79, at a suitable place ontrack 13, and runs overpulleys 75 upward of column 11 and overpulley 77 to a point 80 where the cable is anchored toupper guide track 12. Another cable 81 originates at ananchor point 82 on the bottom track and it runsoverlower pulley 74, up tocolumn 10, whereupon it passes overpulley 76 and crosses over theother cable 78 and continues to ananchor point 83 on the upper track.
Thus, if there were a tendency forupright 9 to rotate clockwise as viewed in FIGURE 4,cable 78 would be placed in tension so as to prevent such movement. Conversely, cable 81 is placed in tension if there is a tendency for the columns to rotate counterclockwise. Consequently, no matter where a force is applied toupright 9 that would tend to cause it to translate along the upper and lower tracks, there will be no rotational movement and the upright will remain perfectly vertical. This eliminates any possibility of skewing and binding of the upright when it is being translated.
Because of the stabilizing influence ofcables 78 and 81, it is possible to havewheels 71 close to each other rather than to have them spaced apart on a wide foot as is required in prior art room mounted tubestands. Hence, it is possible to move the tubest-and over the entire length of the X-ray table 14 on a track that is about the length of the table. This facilitates installing the tubestand in a smaller room than was heretofore possible.
How theupright 9 is adapted to run on rails may be seen in FIGURE 6. Here it will be seen that there are a pair of lateral restraint rollers 84 that are in compressive relation with opposite sides of the upstanding portion offloor track 13 so as to prevent column 11 from moving away from the wall. There is also aroller 71 that bears the vertical thrust of the tubestand column.
It is easy to counterweight the verticalX-ray tube carriage 15 as may be seen in the schematic diagram in FIGURE 5. Acounterweight 85 is arranged for vertical movement in anenclosure 86. The counterweight is suspended on acable 87 which has one end fixed at 88 and another end fixed at 89. Thevertical carriage 15 is suspended oncable 87 in balanced opposition to the tension imposed bycounterweight 85 by means of a pair of grooved pulleys 9t), 91 which are journaled on the back of the carriage for rotation. At the top of the vertical column there are providedrotatable pulleys 92 and 93 over which the cable runs in opposite directions in parallel with the guide track. One part of thecable 87 runs over a fixedpulley 94 on its way to the counterweight suspension pulley 95. Thus, it is seen that when theupright 9 is translated,vertical carriage 15 will remain at the same level since there will be no change in the length of the cable betweenpulleys 92 and 90, for example. Rather,cable 87 will pay out from one end and take up on the other end. An advantage of this arrangement is that thecounterweight 85 need not be carried by the vertical columns and thereby impose additional load when the tubestand is moved. If thevertical carriage 15 is moved up or down,counterweight 85 moves in an opposite direction through a distance that is in the ratio of one-to-one.
In summary, there has been described an X-ray tubestand that is adapted for being located immediately next to the wall of a room away from the X-ray table itself. The tubestand offers a minimum of interference to movements of the operator about the table. The stand is provided with a telescopinug arm that allows frontal and lateral aiming of the X-ray beam with respect to the patient when the table is in any attainable position without requiring the upright to be rotated or the arm to be swung during lateral radiography. The arrangement is such as to allow the guide tracks of the tubestand to be shorter than usual. The X-ray tube carriage can be moved entirely out of the way when it is not in use. The telescoping support also features unitary movement of its sections so as to facilitate their being interlocked or motor driven by a single braking or driving element. In
addition, the size of the tubestan'd is reduced and its stability improved through the use of criss-cross cables which maintain its vertical alignment during translation.
Although a preferred embodiment of the invention has been described, such description is to be considered illustrative rather than limiting, for the invention may be variously embodied and is to be limited only by the terms and scope of the claims which follow.
It is claimed:
1. An X-ray tubestand comprising:
(a) an upright member having guide roller means at its upper and lower ends,
(b) upper and lower horizontal tracks with which the rollers cooperate to allow translation of the upright member lengthwise of an X-ray table,
( c) a carriage that is mounted on the upright member for bi-directional vertical movement thereon,
(d) an extensible and contractible X-ray tube support extending in cantilever fashion from the carriage,
( e) an Xray tube casing that is carried by the support for being moved acrossthe width of the X-ray table, said casing being mounted for rotation about its axis at an end of the support that is remote from the carriage,
(f)-.first and second pairs of pulleys, with each being rotatably mounted near opposite ends of the upright member in substantial vertical alignment with the other pulley in a pair,
(g) a pair of tense cables, each of which runs along the upright member and over each pulley in a pair and then substantially horizontal and opposite directions from each pulley toward fixed terminal points that are substantially on the level of the upper and lower guide track means, respectively.
2. A multiple section telescoping member, for supporting an X-ray tube, in which the sections move in unison when any one of them is moved, comprising:
(a) a fixed section and a plurality of tubular movable sections of progressively smaller size so that the movable sections may slide within each other and the fixed section in a common axial direction,
(b) a shaft that is journalcd for rotation through the wall of each section that is intermediate in size as compared with any two sections that are inside and outside of the intermediate section and which shaft has a pinion on one end and a sprocket on the other,
(c) a rack that is fixed inside one section, that extends in the direction of axis of the section, and that is engaged with the pinion, and
(d) a closed loop of chain that runs over the sprocket and has its ends attached to another section,
(e) whereby application of a force in the axial direction of a movable section will simultaneously impose a force on the other sections to drive them in unison.
3. An X-ray tube support comprising:
(a) a movable carriage,
(b) an axially immovable outer tubular section projecting from the carriage,
(c) a plurality of tubular sections of progressively smaller size that are adapted to slide within each other and the outer section in a common axial direction,
(d) a shaft that is journaled for rotation through the wall of the first section that is the next innermost section from the fixed section,
(c) said shaft having a sprocket on one end and a pinion on the other,
(if) a gear rack fixed on the interior of the immovable outer section and engaged with the pinion, said gear rack being disposed in the axial direction of the sections,
(g) a chain which has its ends fixed to the second next innermost section from the outer section and which runs over the sprocket,
(h) another shaft journaled for rotation through the wall of the second next innermost section,
(i) said other shaft having a sprocket on one end and a pinion on the other end,
(j) a gear rack fixed on the interior of the first innermost section and engaged with the pinion on the other shaft, said gear rack being disposed in the axial direction of the sections,
(k) a second chain which hasits end affixed to the third innermost movable section and which runs on the sprocket of the second shaft,
(1) whereby an axial force applied to any movable section effects an interchange or rotational and translational forces for moving all movable sections equidistantly and in unison, and,
(m) an X-ray tube casing mounted at an end of the most innermost movable section that is remote from the carriage.
4. The invention set forth inclaim 2 including brake means for holding all movable sections by applying a braking force to one of them, said brake means comprising:
(a) a fixedly mounted electromagnetic element, and
(b) means for effecting an attractive coupling between said one movable section and said electromagnetic member when the latter is energized.
5. The invention set forth inclaim 3 including a single brake means for holding the movable sections against axial movement, said brake means comprising:
(a) an electromagnetic member that is mounted on the outermost fixed tubular section, and
(b) means for effecting an attractive coupling between a movable section and said electromagnetic element when the latter is energized.
6. The invention set forth inclaim 3 including an electromagnetic brake for holding all sections against axial movement by holding one of them, comprising:
(a) an electromagnetic stator mounted on the outermost fixed tubular section,
(b) a shaft projecting through the stator and having a brake disk at its one end and a sprocket on the other,
(c) an idler sprocket journaled for rotation on the fixed tubular section, and
(d) a chain that runs over said sprockets and whose ends are attached to the tubular section that is next innermost from the fixed section, (e) whereby attraction of said disk by energization of the electromagnet will hold all sections that are 8 coupled together.
7. An X-ray tube support comprising:
(a) an axially immovable tubular member, I
(b) an outermost movable tubular member next inside the immovable member, 3
(c) an intermediate movable tubular member inside the outermost movable tubular member,
(d) an inner movable tubular member inside the intermediate tubular member, 7
(e) all of said movable members being movable with respect to each other and with respect to the immovable member in the direction of their common axis,
(f) individual shafts journaled for rotation in and extending through the outermost movable member and the intermediate member, respectively, the said shafts having their axes in a plane that is substantially at right angles to the common axis of the members,
(g) toothed means at each end of each shaft,
(h) tooth engaging means that are carried by the outsides of the inner and intermediate members, and by the inside of the immovable and the outermost mov: able member, which tooth engaging means are engaged respectively with the toothed means to rotate the same when any of the tubular members is moved axially.
References Cited by the Examiner UNITED STATES PATENTS 1,303,273 5/1919 Evans 25091 3,037,119 5/1962 Kizaur et a1. 25091 3,118,066 1/1964 Thomas et al. 250-9l 3,121,793 1/1964 Thomas 25091 FOREIGN PATENTS 916,178 1/1963 Great Britain.
References Cited by the Applicant UNITED STATES PATENTS 2,588,124 3/1952 Kizaur.
2,659,827 11/1953 Scag.
2,737,596 3/1956 Haupt.
2,822,477 2/ 1958 Kizaur.
RALPH G. NILSON, Primary Examiner.
A. L. BIRCH, Examiner.