Patent Application
20190247252
This technical solution relates to medical devices such as beds and chairs used in obstetrics, surgery, oncology, gynecology, dialysis, and further for example hospital beds, transport beds or operating tables utilizing a telescopic support column which enables height adjustment of the device.
The current trend in health care beds lies in increasing the height accessibility and manipulation with the rest area. The goal of constructors and designers is to simplify the use of beds for both patients and medical staff. Thus, when reducing the manipulation time, the emphasis is also placed on maintaining easy bed maintenance. Easy positioning allows medical staff to respond faster to patient needs.
Height positioning of health care beds and chairs is currently provided by several mechanisms. The first option is a telescopic positioning by means of manually operated mechanical rastomats or scissor lifts located below the rest area. The bed can be adjusted into several height levels. Positioning is challenging and in the presence of a patient also very difficult, and the height range is not sufficient. Another type of mechanical drive are simple mechanical linear drives converting rotational motion to linear one. Typically, the screw and nut mechanisms, wheel with axis mechanisms, or cams are used. These systems are very simple; however, they have many disadvantages. Positioning speed is limited by the rotation mechanism which requires physical labor.
Another option are electronically adjustable beds with various drive options. The most common are electric, pneumatic and hydraulic drives. The differentiating criteria for the individual drives are shift speed and accuracy, maximum/minimum adjustable bed height, positioning unit size, unit service and maintenance as well as safety and hygienic requirements.
The hydraulic drives require a mechanism consisting, among other things, of a tank, a pump and a valve, which makes this drive a more complex system than other types of drive. A pressurized fluid, usually a hydraulic oil, is used as a medium performing the shift.
The pneumatic drive is a linear drive utilizing compressed air. It achieves very precise positioning even in extreme positions. The entire mechanism is simple to maintain and less expensive to purchase than the hydraulic drive. The compressed air, however, is less effective, more expensive and louder in comparison with other media due to pressure losses.
The electric drive with an electric motor ensures the highest accuracy of position adjustment. During the movement, it is possible to control speed, strength and shift position. The electric motor performs a rotary motion and it is therefore necessary to convert this movement to linear movement. Screws, shafts, belts, or chains are utilized for this task.
Adjustment mechanisms are in health care beds located in telescopic columns consisting of at least two segments. The segments have always the same shape of their floor plan but different size so they can fit into each other in the minimum position. The drive unit performs the raising or lowering of the bed by shifting the individual segments in successive order or simultaneously. The adjustment mechanism of the standard health care bed consists of two or more telescopic columns containing one electric drive for lifting thereof. Modern specific health care beds, such as beds used in gynecology, obstetrics or oncology, are provided with only one telescopic column. Such bed has more utilizable manipulation space between chassis and rest area and its maintenance and operation is also simplified. In the column design, the emphasis is placed on stability of the entire bed and variability in height positioning and tilting of the rest area.
Patent document EP2197406 discloses a mechanism of column lifting by means of a drive and a chain tensioned on toothed gear. Depending on the direction of drive rotation, the bed is lifted or lowered. This method is technologically more complex due to the single motor drive unit and the height manipulation is limited.
Patent document EP1274330 discloses a mechanism of column lifting by means of an electric motor and a rotary spindle with two opposite threads from the inner and outer side. When the spindle is moved, the threaded circular segments begin to move in a different direction, and the bed is lifted or lowered. The lifting or lowering of the bed depends on the direction of the spindle rotation. The mechanism is controlled by one electric motor. This results in a time-consuming lifting of the bed because of the complexity of the mechanism. Friction losses occur in the mechanism and the threads are highly worn.
Patent document EP2594157 discloses a mechanism of column lifting with one electric motor and 2 helical spindles. The spindles functions as a screw-nut mechanism in which the hollow spindle acts as the nut with a hole diameter corresponding to the diameter of the second full spindle which acts as the screw. Column lifting is caused by rotating the spindle by the electric motor and by screwing or unscrewing thereof from the second spindle. In this solution, the minimum bed height is limited by the height of the spindle and the maximum height by combination of the heights of both spindles. The device is complicated and expensive to produce and it suffers from losses caused by the friction and rapid wearing-out of spindle threads.
These prior art technical solutions utilize only one drive unit for the vertical shift. This results in a more time-consuming complete lifting of the rest area. Solutions with a single drive unit are also unable to achieve some of the required minimum and maximum bed positions.
It is therefore clear that no solution of a telescopic column with autonomous drives for three or more column segments which would allow a greater range of minimum and maximum bed height and allowing a rapid shift from the minimum position to the operative position are known in the state of the art. Moreover, the known systems are relatively complicated and expensive to produce.
The above-mentioned drawbacks are to some extent removed by the column according to the present invention. The aim of the invention is to provide a method of vertical movement of medical devices quickly and with sufficient range. This is achieved by mounting a column drive with at least three successive linear drives and two connecting elements.
The lowest linear drive is connected by its bottom side to the chassis of the medical device and by its upper side it is connected to the lower connecting element. The middle linear drive is by its upper side connected to the upper connecting element and by its bottom side it is connected to the lower connecting element. The uppermost linear drive is connected by its upper side to the upper connecting element and by its upper side it is connected to the rest area. The use of connecting elements enables attachment of the bottom side of the middle linear drive below the level of the upper side of the lower linear drive, and the bottom side of the third linear drive can be attached below the level of the upper side of the middle linear drive. This advantageously results in a lower minimum position as the motors in this position abut close to each other.
The column is attached to the bottom side of the rest area at the side edge of the seating portion so that at least 70% of its floor plan is located behind the longitudinal axis of rest area in the direction of the marginal outline of the rest area. From the other side, the column is attached to the chassis. The column is also used as the sole support for the rest area, thus saving space facilitating bed manipulation and maintenance.
The connecting elements include metal plates to which metal or plastic covers of the column drive are attached, which are telescopic segments. These segments are connected by sliding elements which are located on the outer upper side of each segment, except the upper segment, and the inner bottom side of each segment, except the lower segment.
The linear drive according to the present invention is an electric linear drive, converting the rotary motion of the electric motor into a linear tensile or pressure movement by means of a gear and a threaded rod with a nut.
Control of the column drive is located on the lateral side of the rest area or optionally on the rail. Alternatively, the column drive is controlled by a remote manual controller by wire or wireless or by foot wire or wireless controller. Control of the column drive on the rail of the medical device is lockable, which prevents unwanted actuation of the drive and shift of the rest area.
Exemplary embodiment of the invention is a medical device, e.g. a gynecological examination bed or birthing bed such as in
The upper load-bearing area contains a detachable rest area 9. The rest area 9 is adapted for easy maintenance. The rest area may be for example a layer of soft material for interaction with patient's body. The rest area may be formed for example by a foam layer from polyurethane foam, cold foam or a combination thereof. The foam layer is enclosed in a washable cover.
Chassis frame contains wheels. It contains at least three wheels, preferably four, a fifth center wheel can be added for better manipulation. The wheels can have a brake system which can be electrically, mechanically or hydraulically operated. Activation of the braking system may be performed by manual controller, foot controller or it can be automatic after period of time during which the medical device is not moving, or a combination thereof.
An infusion stand holder can be rotatably positioned on the chassis frame. The infusion stand holder can be rotatable between inactive and active position. In the active position, the infusion stand can be inserted into the infusion stand holder. In the inactive position, the infusion stand holder does not protrude outside the chassis frame, thereby eliminating the risk of tripping.
The upper load-bearing area may be composed of for example a back portion 10c, a seating portion 10b and a foot portion 10a. These portions may be formed, for example, by two or more castings and by upper and lower area. The upper and lower area may be, for example, a molded sheet metal. The castings may be interconnected for example by welding, screwing, rivet fastening or gluing to form a central portion. The central portion is connected to the upper or lower area for example by welding, screwing, rivet fastening or gluing. After connecting the upper and lower areas, a portion with enclosed area is created. Enclosure creates a space suitable for e.g. wiring and the surface of the portion is easier to maintain.
The column drive displayed in
Control of the column drive may be for the service staff located on the lateral side of the rest area of the back portion 10c and for the patient it can be located on the right or left side rail 11. Alternatively, the control may be located at any place easily accessible by hand or foot of the staff or the patient, as is known in the prior art. The control of the column drive by the patient can be locked so that he/she cannot move the bed.
In the construction of the medical device, the column drive is located below the seating portion 10b, for example at its edge or in the center. The most advantageous version of the column drive location is the location at the edge of the seating portion, thus as far as possible from the longitudinal axis of the rest area of bed or chair, in the direction of the lateral outline of the rest area. This opens the space below the rest area 9 in this embodiment for manipulation and storage of the foot portion 10a.
The column drive can consist of four or more telescopic segments. These segments are shaped to accommodate the individual linear drives.
In some embodiments, for achieving great maximum height, it is advisable to utilize for example four linear drives and a circular or square cross-section of the telescopic segments. Alternatively, for example, a rectangular or any optional n-angled shape of the telescopic segments, which forms the outer cover of the column drive, may be utilized.
In the exemplary embodiment, all the segments 14a, 14b, 14c, 14d are provided by sliding elements which ensure column guidance during vertical movement and which also serve as a column support.
The uppermost segment 14d is firmly connected to the rest area 9 and the lowest segment 14a is firmly connected to the chassis 12. The lowest segment includes a plate 4 with an inner hole sized approximately to the size of the inner hole of the narrowest segment, firmly connected to the lowest segment at the upper part of the lowest segment. The number of connecting elements is one less than the number of linear drives, and the connecting elements are attached at the upper part of each inner segment. The connecting elements are in this exemplary embodiment plates with the inner hole sized approximately to the size of inner opening of the narrowest segment and the load-bearing portion spaced apart from the metal plates for the location and attachment of the linear drives, wherein the load-bearing portions spaced apart from the metal plates are connected by means of the sheet metal elements 15. In the lowest retracted position, the connecting element plates and the lowest segment plate abut close to each other and all linear drives, including control cables and cables conducting current, are housed essentially in their entirety in the lowest segment without any limitations.
In the exemplary illustrative four-segment embodiment of three linear drives illustrated in
This connection allows to achieve very low height of the rest area 9 by the linear drives 1, 2, 3 in the lowest retracted position, wherein all metal plates 4, 6, 5 abut close to each other in the lowest retracted position shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| PV 2016-582 | Sep 2016 | CZ | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CZ2017/050042 | 9/13/2017 | WO | 00 |
