US3149229A

US3149229A - Tiltable table for use in the radiological examination of patients

Info

Publication number: US3149229A
Application number: US77183A
Authority: US
Inventors: Morel Frans Alfons Maria
Original assignee: Laboratory For Electronics Inc
Current assignee: Laboratory For Electronics Inc
Priority date: 1959-12-30
Filing date: 1960-12-20
Publication date: 1964-09-15
Anticipated expiration: 1981-09-15

Description

Sept. 15, 1964 Filed Dec.

F. A. M. MOREL 3,149,229 TILTABLE TABLE FOR USE IN THE RADIOLOGICAL EXAMINATION OF PATIENTS 5 Sheets-Sheet 1 IN VEN TOR.

7 FRANS ALrofis MARIA MOREL 50 By ATTORNEYS Sept. 15, 1964 F. A. M. MOREL TILTABLE TABLE FOR USE IN THE RADIOLOGICAL Filed Dec. 20, 1960 EXAMINATION OF PATIENTS 5 Sheets-Sheet 2 INVENTOR.

' FRANS ALFONS MARIA MOREL ATTORNEYS Sept. 15, 1964v F. A. M. MOREL 3,149,229

TILTABLE TABLE FOR USE IN THE RADIOLOGICAL EXAMINATION OF PATIENTS Filed Dec. 20, 1960 5 Sheets-Sheet 3 IN VEN TOR.

FIRANS ALFONS MARIA MOREL B wwwwww ATTORNEYS Sept. 15, 1964 Filed Dec. 20, 1960 F. TILTABLE TABLE A. FOR

5 SheetsSheet 4 BY lka 4L,

INVENTOR.

FRANS ALFONS MARIA MOREL ATTORN EYS.

Spt. 15, 1964 F. A. M. MOREL 3,149,229

TILTABLE TABLE FOR USE IN THE RADIOLOGICAL EXAMINATION OF PATIENTS Filed Dec. 20, 1960 5 Sheets-Sheet 5 I INVENTOR. 5O FRANS ALFONS MARIA MOREL ATTORNEYS United States Patent 3,149,229 TILTABLE TABLE FOR USE us THE RADIO- LOGICAL EXAMINATEON OF PATIENTS Frans Alfons Maria Morel, Antwerp, Belgium, assignor,

by mesne assignments, to Laboratory for Electronics,

Inc, Boston, Mam a corporation of Delaware Filed Dec. 20, 1960, Ser. No. 77,183 17 Claims. ((Il. 250-555) This invention relates in general to X-ray equipment and more particularly to a tiltable table for use in the radiological examination of patients.

In medical radiology, specially constructed tables are generally used for receiving the patient who is to be radiologically examined. These tables are generally adapted to operate in conjunction with the other X-ray equipment and commonly include within the body of the table X-ray equipment such as X-ray generating tubes, X-ray film buckys and the like. In addition the tables must provide for a tilting movement of the patient in order to take X-ray photographs at various angles while maintaining the patient immobile with respect to the table. There are a great variety of table constructions used for this purpose; however, a major drawback of many of these tables is that the tilting movements are considerably restricted, hence restricting somewhat the radiological procedures which may be employed readily. Perhaps the fundamental reason for this restriction of movement lies in the length of the table as compared to its normal working height above the floor, such that the rotational are about the transverse axis of the table is quite large. One type of construction which has been used to alleviate this problem is to construct the body of the table, below the circular configuration of the table limits the lengthwise travel of the X-ray tube head severely.

Another approach has emphasized the mechanical aspects of the adjustment and has resulted in many cases in unwieldy and complex mechanisms such as very large gear segments and the like. In addition, many of these mechanisms require that in rotating to the vertical position the table moves beyond the horizontal limits of the space occupied by the table in its normal horizontal position. One desirable adjustment of an X-ray examining table is that which allows the radiologist to raise the examining table in the horizontal position. However, in general the existing table designs do not permit the rotation to a vertical position to be initiated from any horizontal position other than the lowest or norma horizontal position.

It is, therefore, the primary object of the present invention to provide an efficient, economic X-ray examining table apparatus which is capable of vertical adjustment and of being rotated to any vertical elevation up to 90 degrees in either direction from any one of its horizontally level positions.

It is another object of the present invention to provide a completely automatic X-ray table apparatus which can be adjusted vertically and rotated to any vertical elevation up to 90 degrees.

It is still another object of the present invention to provide a completely automatic, vertically adjustable X-ray examining table which provides for full longitudinal travel of the Xray film carriage or tube head contained within it.

Patented Sept. 15, 1964 It is still another object of the present invention to pro-.

vide an economic, rugged, eflicient X-ray table apparatus which may be adjusted to any elevation up to degrees above the horizontal in either direction and in which the table remains substantially within the horizontal limits of the space occupied by the table in its normal horizontal position.

Broadly speaking, the X-ray table of the present invention employs a novel, simple linkage system which provides that the X-ray. table may be easily and efficiently moved through a path of motion which keeps the table substantially within the horizontal limits of the space it originally occupied and which permits the table to be formed with depending elements such as side and end skirts which extend almost to the floor beneath the table. This linkage, which will be described in more detail below, consists of four rotating links, two of which support the table structure above a centrally located base member and the other two of which connect the first two links to each other and the base. Each of the first two supporting links is pivotally connected at one end to the base member near the longitudinal center of the base member. The other end of one supporting link is pivotally attached to the table near one end while the other end of the other supporting link is pivotally attached to the table near its oppositeend. The links are attached to the table in a manner which permits the table to be selectively rotated around either one of these attaching pivots. The connecting links provide that when the table is rotated around the attaching pivot of one of the supporting links, that link itself rotates in the opposite direction around its pivotal connection to the base member. The resultant motion of the table is, then, not circular with respect to the base but rather follows a somewhat irregular curved path. For example, when tilting to the right, as the left hand end of the table moves upward and to the right, the right hand end also moves up and towards the centerline of the base. It is this motion which allows at the same time the movement of the table to remain within the horizontal confines of its original position and also to have a deep rectangular shape since the motion eliminates the usual problem of the lower corner of a rectangular shaped table describing an are which brings it into contact with the floor before the overall table can achieve a 90-degree vertical elevation.

Other objects and advantages will become apparent from the following detailed description when taken in conjunction with the accompanying drawing in which:

FIG. 1 is a perspective view having a cutaway portion to show the internal mechanism of an X-ray table in ac cordance with the principles of this invention;

FIG. 2 is a perspective view of a modification of the X-ray table illustrated in FIG. 1;

FIG. 3 is a cross-sectional view taken along the line 33 of FIG. 2;

FIG. 4 is a perspective view of the X-ray table of FIG. 2 in the raised horizontal position;

FIG. 5 is an illustration partially in perspective and partially in diagrammatic form of the X-ray table of FIG. 2 adjusted to a 90-degree elevation above the horizontal to the right;

FIG. 6 is an illustration of a portion of a diiferent embodiment of an X-ray table in accordance with the principles of this invention having a broken-away section to show the internal mechanism;

FIG. 7 is a diagrammatic side elevation of the X-ray table of FIG. 6 adjusted to an elevation of 90 degrees above the horizontal to the right;

. FIG. 8 is a cross-sectional view taken through the line AA of FIG. 6.

FIGS. 9A and 9B are detailed views of the coupling mechanism in the table of FIG.

FIG. is a cross-sectional View taken through the line BB of FIG. 6.

With reference now specifically to FIGS. 1 and 2, the table structure 1 is seen to have a generally rectangular vertical cross-section, and as indicated in FIG. 3, it also has a generally rectangular horizontal cross-section, thus forming a rectangular box-shaped structure. The upper surface 20, on which the patient to be examined is placed, is formed as a smooth rectangular surface. The body of the table is formed by generally rectangular side panels 21 and 22 and a bottom panel 23. The enclosed center portion is left unobstructed in order to accommodate the sliding film carriage and X-ray tube head (not shown). Outer skirts 24 are mounted to the side panels and cover the linkages, both for appearance and toprevent accidental damage to the mechanism or operator.

The table structure 1 is supportedabove a base member by a linkage system which includes

extendable links

8 and 9 and connecting

links

12 and 13. As is most clearly indicated in FIG. 3, the table I is supported by duplicate linkage systems on the front and back face of the table; however, the operation will be described in terms of the linkage on only one face of the table since in all cases their operation is identical.

Links

3 and 9 are, in this embodiment, telescoping hydraulic cylinders capable of extending to more than three times their original minimum lengths. The fixed portion of each of these cylinders is pivotally coupled to the base member at the

pivots

4 and 5 respectively. The extendable portion 6 of cylinder 8 is pivotally coupled to the table structure at pivot 2, while the extendable portion 7 of cylinder 9 is pivotally coupled to the table structure at pivot 3.

Connecting links

12 and 13 may be formed as pivoted bars, link 12 being pivoted at one end to cylinder 8 at point It) and link 13 being pivoted at one'end to cylinder 9 at point 11. The other ends of

links

12 and 13 are joined together at pivot 14 which is arranged to ride within a T-shaped slot 16 in an upraised portion of the base 15. The slot 16 may be inverted or upright. In FIG. 1, the T-shaped slot is'inverte'd and the connecting

links

12 and 13 are joined near the open end of

cylinders

8 and 9, whereas in FIG. 2 the T-shaped slot is in the normal position and the connecting links are joined to

cylinders

8 and 9 about midway from the length of the fixed portions. Hydraulic lines 5% and 51 supply the hydraulic fluid to the cylinders, the pressure being controlled 'by a conventional hydraulic valve-pump arrangement (not shown), permitting selective extension of either of the cylinders. A pair of bumper blocks 17 and 18' are located at either end of the table and serve the purpose, as will be described below, of both guiding the linkage in its 90-degree elevation position and of stabilizing the table in that position.

The two forms of construction shown in FIGS. 1 and 2 operate in essentially the same manner. Operation of the second form will now be discussed with reference to FIGS. 2, 4, and 5. In FIG. 2 the table is shown horizontally level and in its lowermost position, while in FIG. 4 the table shown horizontally level and partially elevated. In FIG. 5 the table apparatus of FIGS. 2 and 4 is tilted up to the vertical position to the right in bold outline and the dotted lines indicate both the horizontal and oneintermediate position. As indicated in the view of FIG. 2 when the table is in the horizontally level lowermost position, hte pivot joint 14 rests at the lower end of slot 16 and the movable portions 6 and 7 of

cylinders

8 and 9 respectively are fully retracted to a position of minimum extension. In order to raise the table vertically while maintaining it in the horizontally level position, the cylinders must be extended equally, as indicated in FIG. 4. Extending the cylinders equally causes

cylinders

8 and 9 to rotate about

pivots

4 and 5 respectively toward one another; hence, junction 14 is driven upward in slot 16. The equal extension of hydraulic cylinders may be achieved by simultaneously actuating the valve controls for each of the hydraulic lines and 51.

In order to tilt the table 1 vertically to the right from the lowermost horizontal position, as illustrated in H6. 5, it is necessary to extend only cylinder 8. This raises pivot point 2 vertically. When pivot point 2 and consequently the left hand end of table 1 are raised, the table will rotate around pivot point 3, but the raising of pivot point 2 will cause cylinder 8 to rotate about the base pivot point 4, thus pushing rod 12 away and, in the embodiment illustrated in FIG. 2, raising pivot joint 14 within slot 36. Consequently, rod 13 will also be pulled vertically upwards and pivot points 11 and 3 will rotate around the base pivot 5 in the direction of the center of the table. The overall'efiect, then, is that by raising pivot point 2, pivot point 3 is also raised somewhat and brought in towards the center enabling the entire table to rotate to the vertical position without the right-hand lower corner striking the floor. This is illustrated diagrammatically in FIG. 5 where the positions of the

cylinders

3 and 9 are illustrated as being at point a for the lowermost horizontal position, point b for the intermediate position right-hand tilt, and point 0 for the 90-degree tilt to the right.

Link members

12 and 13 are shown only in the position corresponding to the 90-degree vertical tilt in order not to obscure the illustration.

To tilt the table in the other direction, the procedure is opposite to the one just described; in this case it is point 3 only which must be raised and the movements of point 2 are then correlated with those of point 3. The over-all path in tilting in either direction is then not a circular one but rather a somewhat irregular curvature representing the resultant curve described by rotating the table about a rotation axis which is itself rotating in the opposite direction with a diiferent radius.

In tilting the table either to the right or to the left, the hydraulic controls must be selectively operated such that the extension movement is limited to one or the other of cylinders E3 or 9. It should also be noted that if the initial position of the table is in the horizontally level raised position as indicated in FIG. 4, the tilting action may also be initiated from this position. For example, if thetable is to be tilted to the right, then the controls effecting the extension of cylinder 9 must first be operated to retract this cylinder to its minimum extension and then the control effecting cylinder 8 may be operated to extend cylinder 8 to its maximum extension.

The control system may be made completely automatic by conventional programming techniques such that the table will go to any one of a preselected group of positions, such as 15 degrees to the right, degrees to the right, degrees to the right, or the same to the left by flipping a corresponding switch. The same programming techniques may, of course, be used to have a discreet number of preselected raised horizontally level positions.

While the above operation has been described in terms of a single hydraulic cylinder on either end of the table, it is, of course, apparent, as mentioned above, that there is a matching setof linkages on the other face of the table (as illustrated in FIG. 3 cross-section) and actuation of a cylinder actually corresponds to actuating a pair of cylinders such that only the longitudinal axis of the table is tilted. As indicated in FIG. 5, the bumper 18 abuts cylinder h when the table'is in the 90-degree vertical tilt to the right, thus preventing any over-swing of the table. beyond the 90-degree position and giving vertical stability within this position. Bumper 17 serves the same function in a 90-degree tilt to the left.

While, in the embodiments above, the extending elements were shown as hydraulic cylinders, it should be apparent that any means of extending the rotating links will be suitable for operating this table. For example, cylinders actuated by air compression or extended by screw drives and the like may be employed to obtain the same action.

With reference now to FiG. 6 and FIG. 7, a second embodiment of the X-ray apparatus of this invention is shown. As in the previous embodiment, the basic sup port linkage again consists of four rotating links, two of which join the table to the base and two of which join the first two links to each other and-to the base. Turning now to FIG. 6, a portion of the front face of the table is shown with the outer skirt broken away in order to clarify the detail of the operating mechanism. The table structure 1 carries on it two

diagonal track members

63 and 65 respectively. Track 63 is mounted directly to the body of the table, for example being mounted fluish to the front face 59 of the table, and this track 63 runs from a point near the upper righthand corner of the table to a point near the lower lefthand corner. The track 63 would typically be formed of a U-shaped channel member with a hollow center section having inwardly protruding flanges 79 as the track guide means, as is perhaps most clearly illustrated in the crosssectional view of FIG. 10. Extending the length of the track member 63 and confined within its outwardly facing open center channel is lead screw 64, which is mounted in a fashion to allow rotation. Screw 64 is coupled through a coupling unit '77 (as indicated in FIG. 7 and FIG. 9) to a reversible motor 95. The second diagonal track 65 which runs from the upper left corner to' the lower right corner of the table is mounted outboard of track 63 by means of supporting struts 86 through 83. The outboard track 65 is again formed of a channel member having the same structure as track 63, but with the open channel section facing inwardly thus providing that the open sections of each track are facing one another. A second lead screw 66 is mounted within channel 65 with freedom to rotate and is coupled through coupling unit 76 to a second reversible motor 97. A pair of rotating links 61 and 62 which typically might be formed as relatively flat bar members arepivotally connected to base member 50 at

points

53 and 54, respectively. Link 62 is pivotally coupled at its other end to a lead screw follower block 75 at pivot 52. The lead screw block follower 75 is mounted, as is most clearly illustrated in FIG. 10, on lead screw 64 and adapted to ride within track 63. The lead screw follower is thus adapted to ride up and down track 63 in response to rotations of the lead screw 64. Lead screw 64 has a left-hand thread and hence follower block 75 travels downward when the lead screw is rotated clockwise and travels upward when the lead screw is rotated counter-clockwise. Link member 61 is coupled in the same fashion at pivot 51 to lead screw follower 78 mounted on lead screw 66 and the follower 78 is adapted to ride up and down in track 65. The thread on lead screw 66 is reversed; that is, a right hand thread, so that if both lead screws are rotated in the same direction both follower blocks move up or down. A pair of connecting

links

56 and 57 are pivotally coupled at pivot points 70 and 71 respectively to rotating links 61 and 62 respectively.

Connecting links

56 and 57 are pivotally connected at their other ends through

pivots

73 and 72 respectively to a sliding block 55. The

sliding block 55 has two inwardly protruding stud members 74 which ride a vertically elongated slot 66 within a raised center portion 58 of base member 50.

Having described the interconnection of the mechanism, its operation will'now be considered. Considering first the case where both lead

screws

64 and 66 are rothe table 1 frame, yet, relative to the base, both of these pivot points are rotated to a slightly higher vertical position. The over-all effect is to raise the table above the base member while maintaining it in a horizontally level position. The limit of this movement is reached when each of the rotating links 61 and 62 are raised to almost the straight vertical position, which places the table in its uppermost horizontally level position. From this position the table may be lowered again to its initial low horizontally level position by reversing the drive on the lead screws 64 and 66.

In order to tilt the table, either to the right or to the left, from its lowermost horizontally level position, only one of the lead screws need be rotated. Thus, for example, in order to tilt the table to the right (as indicated in FIG. 7), lead screw 66 is rotated clockwise, thus driving the follower 78 to the lower end of track member 65. This action forces rotating link 61 up to the vertical position. Rotating link 62 is also pulled to the vertical position due to the interconnection through

connesting links

56 and 57. The resultant position of the table is, as indicated in FIG. 7, a -degree elevation to the right. In order to return to the horizontally level lowermost position, lead screw 66 is rotated counter.- clockwise which lowers the table back to the position indicated in dotted lines in FIG. 7. In order to tilt the table to the left the same procedure is followed with regard to lead screw 64 which is rotated clockwise while lead screw 66 is not rotated.

If it is desired to tilt the table to one side, initiating the action not from the lowermost horizontal position, but from some intermediate raised horizontally level position, then one lead screw is first rotated counter-clockwise until its follower block is driven to the uppermost point of the track and the other lead screw is then rotated clockwise to raise its corresponding end of the table. For example, if it is desired to tilt the table to the right from an intermediate position then lead screw 64 is first rotated counter-clockwise until follower block 75 is in the position as indicated in FIG. 6 and then lead screw 66 is rotated clockwise thus raising the left-hand end of the table.

In the above-described tilting action of the table, it is seen that the path of motion of the table is again, as in the embodiment illustrated in FIGS. 1 and 2, one in which one end of the table is rotated about a pivot point in the opposite end of the table and that pivot point is simultaneously rotated in the opposite direction about a pivot point in the base. Thus, tilting the table to the right, the left-hand end of the table is rotated around pivot point 52, while pivot point 52, being fixed to bar 62, is rotated with it towards the center line of the base around pivot point 54. Therefore, again in this embodiment the right-hand end of the table in a tilt to the right is moved up and towards the center line while the lefthand end is moved up towards the top position, thereby providing that a deep rectangularly shaped table does not collide with the floor on which the base member is set.

The driving source for the lead screws in the embodiment illustrated in FIGS. 6 and 7 may be any conventional motor arrangement, the reversible electric motors being typical examples. The motors may be located as shown within the body of the table and coupled to the lead screws through couplings as are illustrated in FIGS. 9A and 9B. In FIG. 9B, the coupling for the lead screw 64 which intersects the bottom of the table is shown with a flexible joint in order to provide that the coupling extends the minimum amount below the lower edge of the table. The lead screw 64 in FIG. 9B is connected through a thrust bearing 99 to a flexible joint 90 which permits flexibility in the vertical plane but which is pinned through pin 91 to provide for rotational coupling. This joint is coupled through another thrust bearing 98 to a bevel gear 162 which is operating in conjunction with a 90-degree displaced bevel gear 193, the latter being driven by the motor. 95. The coupling '76 for lead screw 66 is similar, but does not require a flexible joint since it is not positioned in close proximity to the upper edge of the table.

The second embodiment of the X-ray table apparatus has utilized track members with carrier blocks adapted to be driven along the track members, which carriers have been pivotally attached to the upper ends of the rotating link arms. While the specific apparatus discussed has employed lead screw drives for controlling the motion of the carrier blocks, the invention is not so limited, but includes any other suitable means of controlling the position of. the pivotally attached carriers within the track members. Similarly, the tracks may be of dif-' ferent construction and may be replaced by other types of guide means adapted to define the paths of travel of the carrier blocks. Having described the invention herein, it is apparent that many modifications and improvements may now be made by those skilled in the art, and it is intended that the invention disclosed herein should be limited only by the spirit and scope of the appended claims.

What is claimed is:

1. X-ray apparatus comprising, a generally rectangular box-shaped table structure; a base member disposed generally in the horizontal plane beneath said table structure in close proximity to the bottom of said table structure; elevating means adapted to vertically raise said table structure above said base member up to a predetermined distance and to maintain said table structure at any selected increment of said predetermined distance; positioning means adapted to position and support said table structure at any elevation of its longitudinal axis up to 90 degrees above horizontal; said positioning means co-acting with said elevating means in such a manner that said positioning action may be initiated from any incremental position of said elevating means.

2. X-ray apparatus comprising, a generally rectangular box-shaped table structure; a relatively rigid base member disposed generally in the horizontal plane; means for positioning and supporting said table structure at any elevation of its longitudinal axis up to 90 degrees above the horizontal; said elevation being obtained by rotating in a first direction one end of said table structure in a circle centered on a first axis of rotation transverse of said table structure longitudinal axis and located within said table structure near the opposite end thereof and simultaneously rotating in the opposite direction said first axis of rotation of said table structure in a circle centered on a second axis of rotation located within said base member.

3. X-ray apparatus comprising, a table and a relatively rigid base; means adjustably supporting said table upon said base and including a first pair of links, each having an end pivotally afiixed to respectively spaced points on said base and an opposite end pivotally affixed to respectively spaced points on said table; a second pair of links each having an end pivotally afiixed to a respective one of said first links; means for pivotally joining the opposite ends of said second links; guide means for constraining the motion of said pivotally joined ends of said second links to a limited path; and means for axially extending the length of either and both of said first links.

4. X-ray apparatus comprising, a table and a relatively rigid base; means adjustably supporting said table upon said base and including a first pair of links, each having an end pivotally afiixed to respectively spaced points on said base and an opposite end pivotally affixed to respectively spaced points on said table; a second pair of links each having an end pivotally aifixed to a respective one of said first-links; means for pivotally joining the opposite ends of said second links; guide means for constraining the motion of said pivotally joined ends of said second links to a limited path, said guide means being secured to said base and being disposed intermediate of said first links, said limited path being T-shaped in form,

and means for axially extending either and both of said first links; means on said table co-acting with said first and said second links for compelling the motion of said pivotally joined ends of said second links into a restricted portion of said T-shaped path under conditions of substantially maximum extension of either one of said first links under conditions of substantially minimum extension of the other one of said first links.

5. X-ray apparatus comprising, a table and a relatively rigid base; means adjustably supporting said table upon said base and including first and second links, each having an end pivotally aifixed to respectively spaced points on said base and an opposite end pivotally affixed to respectively spaced points on said table; third and fourth links, each having an end pivotally affixed to a respective one of said first and second links; means for pivotally joining the opposite ends of said third and said fourth links; guide means for constraining the motion of said pivotally joined ends of said third and fourth links to a limited path, said guide means being secured to said base and disposed intermediate of said first and said second links and substantially centered on the longitudinal dimension of said table, said limited path being T-shaped in form; means for axially extending either and both of said first and said second links, whereby, by extending said first link and not extending said second link said table may be elevated up to degrees above the horizontal in one direction, by extending said second link and not extending said first link said table may be elevated to 90 degrees above the horizontal in the other direction and by extending both said first and said second links said table may be displaced vertically.

6 X-ray apparatus comprising, a generally rectangular table member; a base member; support means; said support means having first and second hydraulic cylinder elements, each of said cylinder elements having a fixed portion and an extendable portion; said extendable portion being adapted to extend in a direction along the loagitudinal axis of said cylinder member; said fixed portion of each of saidcylinders being pivotally mounted to said base member; said extendable portion of said first cylinder member being pivotally mounted to said table member at a point near one end thereof; said extendable portion of said second cylinder element being pivotally mounted to said table member near the opposite end thereof; first and second links, said first link having one end connected pivotally to said fixed portion of said first cylinder member; said second link having one end pivotally connected to said fixed portion of said second cylinder element; the other ends of said first and second links being pivotally joined together; means extending vertically from said base member and defining a T-shaped guide; and means containing the path of motion and pivotal joint to said T-shaped guide.

7. X-ray. apparatus in accordance with claim 6 wherein said support means is adapted to tilt said table longitudinally to the left by extending said hydraulic cylinder element coupled to the right-hand end of said table and to tilt said'table longitudinally to the left by extending said hydraulic cylinder element attached to the right-hand end of said table.

8. Apparatus in accordance with claim 6 wherein the lower limit of said T-shaped slothas a higher vertical position than the vertical position of the pivotal connections between said links and said hydraulic cylinders.

9. X-ray apparatus comprising, a generally rectangular table member; a base member; support means, said support means having at least one pair of hydraulic cylinders, each of said hydraulic cylinders having a fixed portion and an extendable portion, each of said extendable portions being adapted to extend in a direction along the longitudinal axis of its respective cylinder, said fixed portion of each of said cylinders being pivotally mounted to said base member; said extendable portion of each of said hydraulic cylinders being pivotally mounted at longitudinally spaced points to said table member; links,

each of said links having one end pivotally connected to said fixed portion of one of said hydraulic cylinders, the other ends of said links being pivotally joined together; means extending vertically from said base member, said means including a vertical slot having the form of an inverted T, said pivotal joint being adapted to ride within said slot.

l0. X-ray apparatus comprising, a generally rectanguular boxshaped table and a relatively rigid base, said table having a normal position with respect to said base in which the bottom of said table is disposed in close proximity to said base and said table is generally in a horizontal position; support means, said support means including first and second links, each having an end pivotally afiixed to respectively spaced points on said base and an opposite end pivotally afiixed to respectively spaced points on said table, said links being confined within said table in said normal horizontal position; third and fourth links each having an end pivotally affixed to a respective one of said first and second links; means for pivotally joining the opposite ends of said third and fourth links; guide means for containing the motion of said pivotally joined ends of said third and fourth links to a limited path; means for axially extending the length of either and both of said first and said second links whereby by extending said first and said second links selectively said table may be positioned at any elevation up to 90 degrees above the horizontal.

ll. X-ray apparatus comprising, a generally rectangular box-shaped table and a relatively rigid base; means adjustably supporting said table upon said base and including first and second pairs of links, each having an end pivotally affixed to respectively spaced points on said base, each of said first pair of links having an opposite end pivotally affixed to respectively spaced points on one side of said table, each of said second pair of links having an opposite end pivotally afiixed to respectively spaced points on the opposite side of said table; a third pair of links each having an end pivotally affixed to a respective one of said first pair of links; means for pivotally joining the opposite ends of said third pair of links, a fourth pair of links each having an end pivotally afi'ixed to a respective one of said second pair of links; means for pivotally joining the opposite ends of said fourth pair of links; guide means for constraining the motion of said pivotally joined ends of said third pair and said fourth pair of links to a limited path; means for axially extending selectively each of said first and said second pair of links.

12. X-ray apparatus comprising, a generally rectangular table member; a base member; support means; said support means including first and second hydraulic cylinder elements, one end of said first hydraulic cylinder element and one end of said second hydraulic cylinder element being pivotally mounted to said base member, the other end of said first hydraulic cylinder element being pivotally mounted to said table element near one end thereof, the other end of said second hydraulic cylinder element being pivotally mounted to said table member near the other end thereof; said support means being adapted to tilt said table in a longitudinal direction by rotating the pivot connection of said first cylinder element and said table around the pivot connection of said second cylinder element and said table while the pivot connection between said second cylinder element and said table member is describing a circular path around the pivot connection between said second hydraulic cylinder and said base member.

13. X-ray apparatus comprising, a generally rectangular table member; a generally rectangular base member; support means; said support means including first and second pairs of hydraulic cylinder members, each of said hydraulic cylinder members being extendable along its longitudinal axis; actuating means adapted to independently extent each of said pairs of hydraulic cylinder members, one end of each of said first pair of cylinder members being pivotally connected to said base member near the longitudinal center thereof, each of said second pair of hydraulic cylinder elements having one end pivotally connected to said base member near the longitudinal center thereof; the other end of each of said first pair of hydraulic cylinder members being pivotally mounted near one end of said table member, the other end of each of said second pair of hydraulic cylinder members being pivotally mounted to said table member near the other end thereof; means coupling said first pair of hydraulic cylinder elements to said second pair of hydraulic cylinder elements in a manner so that any motion of said first pair of cylinder elements around its pivot connection to said base member results in a related motion of said second pair of hydraulic cylinder elements around its pivot connection to said base member.

14. X-ray apparatus comprising, a generally rectangular box-shaped table member; a base member; first and second support members; first and second track members fixed to said table member, said first track member running from a point near the top of said table member at the left-hand end thereof to a point near the bottom of said table member at the right-hand end thereof, said second track member running from a point near the top at the right-hand end thereof to a point near the bottom at the left-hand end of said table member; first and second lead screws, said first lead screw being mounted within and coextensive with said first track member, said second lead screw being mounted within and coextensive with said second track member; first and second lead screw followers, said first lead screw follower being mounted on said first lead screw and adapted to travel in one direction when said first lead screw is rotated clockwise and in the opposite direction when said lead screw is rotated counter-clockwise, said second lead screw follower being mounted on said second lead screw and adapted to travel in one direction when said second lead screw is rotated clockwise and in the opposite direction when said second lead screw is rotated counter-clockwise; one end of each of said support members being pivotally connected to said base member, the other end of said first support member being pivotally connected to said first lead screw follower, the other end of said second support member being pivotally connected to said second lead screw follower; first and second links, one end of said first link being pivotally coupled to said first support member, one end of said second link being pivotally coupled to said second support member, the other ends of each of said links being pivotally joined together so as to form a pivot joint; guide means supported by said base member, said guide means providing a vertical path for said pivot joint; means adapted to independently rotate each of said lead screws for elevating said table member.

15. Apparatus in accordance with claim 14 in which said first and second lead screw followers are nonrotatably confined within said first and second track members respectively.

16. X-ray apparatus comprising, a table member; a base member; first and second support members, one end of each of said first and said second support members being pivotally coupled to said base member; first and second track members fixed to said table member, said first track member extending from a point near the top of said table member at one end thereof to a point near the bottom of said table member at the opposite end thereof, said second track member extending from a point near the top of said table member at the said opposite end thereof to a point near the bottom of said table member at the other end thereof; first and second carrier members, said first carrier member being adapted to ride along the longitudinal axis of said first track member and said second carrier member being adapted to ride along the longitudinal axis of said second track member, the other end of said first support member being pivotally connected to said first carrier member and the other end of said second support member being pivotaily connected to said second carrier member; positioning means adapted to independently position each of said carrier members at any point along its respective track member; coupling means coupling said first and said second support members in such a manner that any rotational motion of one of said support members around its said pivot connection to said base member induces corresponding rotational action of said other support memher around its said pivot connection to said base member.

17. X-ray apparatus comprising, a table and a relatively rigid base; means adjustably supporting said table upon said base and including a first pair of links each having an end pivotally afifixed to respective spaced points on said base; a second pair of links each having one end pivotally affixed to a respective one of said first links; means for pivotally joining the opposite ends of said second links; guide means for constraining the motion'of said pivotally joined ends of said second links to a limited path; coupling means for coupling the opposite ends 12 of each of said first pair of links to said table in such a manner that said table can be rotated around said opposite end of one of said first pair of links while said first pair of links are rotating'about said base member.

References Cited in the file of this patent UNITED STATES PATENTS