US2775496A - Tilting x-ray medical examination table - Google Patents

Description

Dec. 25, 1956 D. E. BERGGREN TILTING X-RAY MEDICAL EXAMINATION TABLE Filed April 22, 1954 INVENTOR DETLOF EMANUEL BERGGREN AGEN T i i i s 2,775,496 TILTlNGX-RAY MEDICAL EXAMINATION TABLE Detlof Emanuel Berggrem. Eindhoven, Netherlands, as-

i sigor to Hartfo-d National Bank and Trust Company,

4 u icati n prm, 1954, sefi No. '424,997

Claims priority, application N etherlands May 13, 1953 I I "1 claim; {C li 31I-`-6) -This invention relates to-a table utilized in X-ray medical examinationsp i ing tablesare available in which the'position of the supportingsurfajce for the patient `is varied by rotatingthe `table top about a horizontal axis; The table top must be capable of being arranged not' only horizontally but also vertically and must be capable of assuming intermediate positionsg* 1n'addition',it'is 'desirablefo'r the :spitabe exceed a predetermined value and the half length of the table top generally exceeds this value. If the axis of rotation should lie in the middle of the table top, several advantages would be obtained. The construction can be lighter 'and less material is required. Such a device could be manufactured cheaper if the realization of the symmetrical arrangement would not ental complications. The difference between the half length of the top and the height of the supporting surface above the floor requires the table top to shift longitudinally also during rotation.

The structural parts used in different tables to permit the table top to be fixed in any desired position and which also cooperate with the driving members to etfect the rotary movement of the table top due to their weight increase the mass of the parts required to be moved. In addition to the known semi-circular discs which are secured to the table top and are driven along their circumference use has been made of rods to revolve the table top. Although the last-mentioned embodiment increases the weight of the table top to a lesser extent, in practice the first-mentioned manner of driving the table top is used almost exclusively.

It is an object of the invention to restrict the weight of the moving parts of a supporting table to a minimum and also to reduce the inertia forces in other respects. The present invention permits the symmetrical arrangement in which these forces are reduced to a minimum to be approximated. According to the invention the table top is rotatable without shifting along a curved sur-face of a supporting base. In addition, use is made of flexible pulling means to connect a rotary disc arranged in the base and driven by a driving mechanism to the table top at two points of application lying on either side of the point at which the contact surface of the table top rests upon the curved surface of the base. The said connecting means may be chains. To prevent the table top from shifting when it is revolved about the curved surface use may be made of steel tapes or similar connecting means which from both ends of the table top are slun g over the curved surface of the base and on either side 2,775,49'6` Patented Dec. 25, 1956 2 thereof are firmly attached. A groove and bead connection by means of which the surfaces ofcontact of the table top and the rounded base-head engage each other prevents the table top from being displaced transversely. The" above andbther, features, objects andadvantages of the present invention will be fully understood from the following description considered in connection with the accompanying llustrative' drawings.`

Fig. 1 is a diagrammatic view of the X-ray tablearrangement embodying the present invention,

Figs. 2 and` 3 `are diagrammatic views of alternate e'mbodiments of thepresent invention. i `The construction is based on recognition of the fact that two curves determined by difierent equations may partly coincide upon a proper choice of some dimensions.

.i t This will be illustratedin Fig. 1 of the drawing. 573 For medical examination by means of X-rays` support- Referring more particularly to -Figure 1 the numeral 1 designates the table top and 2 a surface of the base 5 `which iscircularly curved about a point 3 and along which` the table top can rotate. If this movementis considred as a rotation of the base withrespect to thetable top,1the cente` 3` of the`curved` surface 2 is seen tofm'ove to `3 'alongja stigightlinfe. g Theibase comprses a disc 1 7 which is 'rotatabl eabout "the 'ce nter l "This mov e"s^"to 4 along part of a cycloid upon rotation of the table. It is supposed that this movement is such that the distance of the point 4 relatively to the table top 1 is equal to that of the point 4. This cycloid is determined by the radius of the circle 2 and the distance between the points 3 and 4.

The point 4 is connected to two points 6 and 7 of the table top 1 in that a belt rope or chain attached at these points is arranged over a rotary disc 17. consequently point 4 must also describe an ellipse of which the lines 8 and 9 are the radius Vectors. It is possible to construct an ellipse which has the points 4 and 4 and the apex 4 in common with the cycloid described above by a proper choice of the joining line 6-7. The foci 6 and 7 :follow from this Construction. It has been found possible for the position of the joining line to be arranged so that the two curves are substantially coincident along the distance covered by the angle of rotation of a value of Furthermore, upon` a proper choice of the dismensions the' deviation is found to -be so small that it can easily be ob- Viated by the use of a rotary disc which is arranged resiliently.

This leads to the arrangement shown diagrammatcally in Fig. 2. In this figure the table top is shown in different positions and in addition the points are indicated at which the center of gravity 10 of the table top carrying a patient is located in each of the positions. When the top 1 is rotated along the surface 2, the center of gravity 10 moves along the indicated curve 19. From this it will be seen that the difference of height described bythe center of gravity in a complete rotation is very sli-ght and much smaller than if the top rotates about a stationary axis consequently the energy required to rotate the table top can also be less.

Since the radius of the surface 2 is greater the symmetrical arrangement is approximated. However, the increase of this dimension cannot be pushed too far since this causes the stablity of the table top 1 to decrease as it approximates to its vertical position. In addition, the increase of the curvature of the cycloidal course of the point 4 causes the distance between the points 6 and 7 in which the connecting means of the table top 1 are attached to decrease with a resultant decrease of the sta bility. consequently the radius must be made as large as possible but not too large, for example not exceeding one half of the height of the space available below the table top in its horizontal position.

The most advantageous arrangement of the rotary disc is at as small as possible a height above the floor on the l'e'bise'ting "the angle of rotation. In this case it is spaced' 'from the' table top 'by"a 'maximum 'distance 'and `it describes a symmetrcal course relatively thereto.

Fi g. &shows the arrangement of the tabletop 1. on the base* andfthe'means preventingithe table *top f'omshift- 'n'g relativlyfto the curved surface 2. "These means are int'he "form offiexib'le 'tapes` 11 and l'zmadeflor example, of steel. 'One o'f 'these tap'es `is attathed to the table top 1 at I 3 and to .the'base 5 at 1.4. Tape connects to the point-15 at one end of the table top 1 and tape 12 .connects at one of its ends to the point 16 of the base 5. The motar-y disc .is designated :17. It .acts :as a driving member for the t-ape .or chanlS: attac'hedto the table top 1 :at .the two ;points -6 and 7. -Rotation ;of the dis'c 17 causes the position of'the :table .top to vary. For this punpose a flrivin'g;mechanismbuiltaintothe base may be -use'd whidh'is actuated by*handor by means of `an e'lectric What is claimed is:

'X-*ray `medical examination table 'comprisinga base having at least one curved tsurface, a table top rotatable on said curved surface, the radius of said curved surface not exceeding /z the height measured from the bottom of said base to the bottom :surface of said table top, a rotating disc, means mounting said disc on said base, and connecting means comprisin'g at least one flexible tape' fixed to points t opposite ends of said base and-engaging said ?curved surface and .said table top, and another exible tape Secured at both ends to -spaced points "on said table top, a part of the intermediate portion of said other flexible tape being passe'd arou'nd and in e'ngagement with said-disc. i

Referencescited i thefile of this patent UNITED STATES PATENTS 'Francen Mai'. 1'948

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