Hydraulic lifting columns and medical devices

Abstract

To provide an improved hydraulic elevation support capable of simply attenuating stage transition impact shock in moving the elevation support with high cost performance.SOLUTION: A hydraulic elevation support 1, in particular for a medical device, includes a hydraulic cylinder unit, a base element 2, a carrier element 3 and at least one of intermediate elements 4, 5. The hydraulic cylinder unit is constituted to move the elevation support 1 along a moving axis FA between a contraction position and an extension position. The hydraulic elevation support 1 further includes at least one first engagement member 6 disposed on the carrier element 3 and formed independently from the carrier element 3, and the first engagement element 6 is brought into contact with the intermediate elements 4, 5 when the elevation support 1 is moved between the contraction position and the extension position to drive at least one of the intermediate elements 4, 5. The first engagement element 6 has an attenuation element, and the attenuation element is, in particular, made of plastic.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a hydraulic lifting column, and more particularly to a medical device equipped with such a lifting column. [Background technology]

[0002] Such lifting columns are used in particular in the medical field, for example for operating tables, surgical robots or other medical devices, the purpose of which is to adjust the height of a medical element fixed to the lifting column, for example the lying surface of an operating table, as gently as possible relative to the floor.

[0003] The demands on these hydraulic lifting columns have been increasing in recent years, especially due to the rapid progress seen in the further development and improvement of a wide variety of surgical procedures, as well as due to the space requirements and comfort specifications of hydraulic systems. Such lifting columns are especially constructed of a telescopic design including several stages. Engagements provided between the stages ensure that the respective stages are moved together when the lifting column is moved.

[0004] For example, it may be necessary to move the lifting column during surgery if the patient needs to be repositioned, for example by changing the height of the operating table. When moving the lifting column or the operating table between individual stage transitions, noticeable jerking and audible impacts may occur as the respective stages are moved. Such stage transition impacts occur especially when the engagement members of one stage abut the engagement members of the other stage and the engagement members begin to drive the other stage. The impacts are caused by the sudden large static friction compared to the sliding friction that must be overcome to move the stage to be transported. To dampen such stage transition impacts, damping engagement members are preferably used.

[0005] Hydraulic lifting columns with corresponding engagement members are known from the prior art. These use complex metal sliding elements between the stages to reduce shocks. These must be greased and the gaps between the sliding elements must be precisely adjusted. However, very complex and expensive spring damper systems, e.g. torsion spring systems, which are also maintenance intensive, are also used as engagement members for damping.

[0006] It is therefore an object of the present invention to provide an improved hydraulic lifting column in which stage transition shocks as the lifting column is moved can be damped simply and cost effectively. Summary of the Invention

[0007] This problem is solved by a hydraulic lifting column according to claim 1. Preferred further embodiments are set out in the dependent claims.

[0008] The hydraulic lifting column according to the invention comprises a hydraulic cylinder unit, a base element, a carrier element and at least one intermediate element. The hydraulic cylinder unit is configured to move the lifting column along a movement axis between a retracted position and an extended position. At least in the retracted position, the at least one intermediate element is arranged between the base element and the carrier element. The carrier element and the at least one intermediate element can be moved relative to the base element along the movement axis by the hydraulic cylinder unit acting on the carrier element. The lifting column further comprises at least one first engagement member arranged on the carrier element and formed separately from the carrier element, where the first engagement member abuts against the intermediate element and drives the at least one intermediate element when the lifting column is moved between the retracted position and the extended position. It is preferred that the first engagement member comprises a damping element, which is made from plastic. It is preferred that the engagement member is a one-piece engagement member, i.e. an engagement member consisting of only a single part. In other words, the engagement member and the damping element can be provided as one-piece, unitary member.

[0009] In this way, the engagement member can drive the intermediate element when the carrier element is moved, so that when the engagement member of the carrier element abuts the intermediate element during extension, the intermediate element is extended. The damping element of the engagement member absorbs the impact upon abutment, which is also referred to below as "stage transition impact". The damping element made from plastic results in a simple and cost-effective engagement member of only one component.

[0010] The base element is preferably fixed to the floor, for example screwed into place. Of course, it is also conceivable that the base element is mounted on a chassis. Such a chassis can preferably be fixed relative to the floor, such that further movement of the chassis relative to the floor can be prevented.

[0011] In addition, the hydraulic lifting column may comprise at least one second engagement member arranged on the intermediate element and formed separately from the intermediate element, where the first engagement member is configured to abut the second engagement member, which is considered part of the intermediate element when arranged on the intermediate element. This allows driving of the intermediate element by moving the carrier element along the movement axis. Further engagement members may be provided, for example, on the base element or on other intermediate elements. The second engagement member may comprise, for example, a damping element, which may be made from plastic. The second engagement member may have the same characteristics as the first engagement member.

[0012] The damping element is made from a first plastic material and a second plastic material, the first plastic material preferably having a higher elasticity than the second plastic material. The damping element preferably has a higher elasticity transverse to the axis of movement than parallel to the axis of movement. Meanwhile, the stiffness is higher transverse to the axis of movement than parallel to the axis of movement. This is achieved by using two different plastics with different properties in one component. As a result, a different stiffness, elasticity and damping is achieved in the direction of the axis of movement than transverse to the axis of movement.

[0013] The damping element is preferably formed as a one-piece member. The damping element is preferably an injection-molded damping element. The one-piece construction of the damping element means that it can be cost-effectively produced without additional components, which further allows a reduction in the number of assembly steps and the duration of the assembly. The damping element may be produced using a two-component injection molding process, so that it can be made from two different plastic materials as mentioned above.

[0014] The damping element is preferably configured to be elastic in the direction of the axis of movement and rigid transversely to the axis of movement. In other words, the damping element is preferably more elastic in the direction of the axis of movement than transversely to the axis of movement. When the engagement members of the lifting columns abut against each other, the damping element allows elastic deformation in the direction of the axis of movement, while deformation and crushing transversely to the axis of movement is significantly reduced or prevented. This can, for example, prevent the engagement members from unintentionally loosening or coming off, while at the same time damping stage transition shocks.

[0015] In addition, the first engaging member can have a first end and a second end transverse to the axis of movement and a rod connecting the first end and the second end. This allows the realization of a geometrical directional dependency in only one component. This leads to a higher stiffness of the engaging member transverse to the axis of movement and a higher elasticity in the direction of the axis of movement, and therefore also to its firm retention in the respective element of the lifting column.

[0016] The damping element preferably has an elastic part made from a first plastic material. The bar is made from a second plastic material, which separates the elastic part into an upper elastic part and a lower elastic part in the direction of the movement axis. This ensures stability of the damping element transversely to the movement axis. The upper and lower elastic parts ensure better shock absorption.

[0017] Preferably, an upper flexible arm portion is formed at each of the first and second ends in the direction of the movement axis and surrounds the upper elastic portion such that the upper elastic portion is disposed between the rod and the upper arm portion. The arm portion prevents the elastic element from bending laterally.

[0018] Preferably, the lower flexible arm is formed at each of the first end and the second end in the direction of the movement axis, and surrounds the lower elastic part so that the lower elastic part is disposed between the rod and the lower arm. The number of arms is not limited. For example, only one flexible arm may be formed to connect the first end to the second end.

[0019] The first engagement member preferably has a first plane of symmetry parallel to the direction of the axis of movement and a second plane of symmetry preferably perpendicular to the direction of the axis of movement. The symmetrical shape of the engagement member allows for simple and quick installation of the engagement member and suitable damping during extension and retraction of the lifting column. This means, for example, that only limited attention to specific orientations is required during installation.

[0020] A sliding lining is preferably attached to the carrier element and to the at least one intermediate element. The sliding lining can further preferably be attached to the base element. The sliding lining can be used to reduce the static and sliding friction between the carrier element and the at least one intermediate element and the base element, so that the forces required during stage transitions are reduced. This can reduce the impact and audible noise during extension of the lifting column. It is possible to provide sliding surfaces in individual areas of the elements, for example to reduce costs. However, it is also possible for most of the elements to be fitted with sliding linings in order to reduce friction to a minimum.

[0021] The invention further relates to a medical device comprising a lifting column as described above.

[0022] The invention will be explained in more detail below with reference to embodiments shown in the drawings, in which: FIG. [Brief description of the drawings]

[0023] [Figure 1] FIG. 2 is a view of the lifting column fully extended. [Diagram 2] 2 is a cross-sectional view of the fully extended lift column of FIG. 1 taken along line BB. [Diagram 3] FIG. 3 is a detailed view of region Y of the engagement member on the extended lift column of FIG. 2. [Figure 4] FIG. 13 is a diagram of the lifting column fully retracted. [Diagram 5] FIG. 5 is a cross-sectional view of the fully retracted lift column of FIG. 4 taken along line AA. [Figure 6] 6 is a detailed view of region Z of the engagement member in the retracted lift column of FIG. 5. FIG. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which like reference symbols indicate corresponding or identical elements in the various drawings, and in which:

[0025] FIG. 1 shows the lifting column 1 in a fully extended state. The lifting column 1 is of telescopic design and comprises a base element 2, a carrier element 3, a first intermediate element 4 and a second intermediate element 5. The first and second intermediate elements 4 and 5 are at least partially arranged between the base element 2 and the carrier element 3. The second intermediate element 5 is at least partially arranged in the carrier element 3. The first intermediate element 4 is at least partially arranged in the second intermediate element 5 and the base element 2 is at least partially arranged in the first intermediate element 4. The base element 2 can, for example, fix the lifting column 1 to a floor or a mobile chassis (not shown) via a base plate (not shown). In particular, a medical device (not shown), such as an operating table, a surgical robot, etc., can be attached to the carrier element 3. Of course, the lifting column 1 may only have the first intermediate element 4 or more than two intermediate elements.

[0026] The lifting column 1 also has a hydraulic cylinder unit (not shown) configured to move the lifting column 1 along a movement axis FA between a retracted position and an extended position. The retracted position represents the position of the lifting column 1 in a fully retracted state, as shown in Figure 4. The extended position represents the position of the lifting column 1 in a fully extended state, as shown in Figure 1.

[0027] FIG. 2 shows a cross-sectional view of the fully extended lifting column 1 of FIG. 1 along the line BB. The lifting column 1 comprises several engagement members 6, which will be described in detail below. Two of the engagement members 6 are arranged on the base element 2, where two engagement members 6 are arranged in the upper half of the base element 2 in the direction of the movement axis FA. Two further engagement members 6 are arranged on the carrier element 3, where two further engagement members 6 are arranged in the lower half of the carrier element 3 in the direction of the movement axis FA. The engagement members 6 arranged on the carrier element 3 may also be referred to as first engagement members within the meaning of the present invention. On the first intermediate element 4, two of the engagement members 6 are arranged in the lower half of the first intermediate element 4 in the direction of the movement axis FA, and two of the engagement members 6 are arranged in the upper half of the first intermediate element 4 in the direction of the movement axis FA. The second intermediate element 5 has the same number and arrangement of engagement members 6 as the first intermediate element 4. The engagement members 6 arranged on the intermediate elements 4, 5 may also be referred to as second engagement members within the meaning of the present invention. The engagement members 6 are formed separately from the base element 2, the first and second intermediate elements 4, 5 and the carrier element 6. The engagement members 6 located on the upper half of the elements are hereinafter referred to as the "upper engagement members". The engagement members 6 located on the lower half of the elements are hereinafter referred to as the "lower engagement members".

[0028] Passage openings 7 are provided in the base element 2, the first and second intermediate elements 4, 5 and the carrier element 3, within which the engagement members 6 are arranged such that they project inwards and outwards of the respective elements. A passage opening 7 is provided for each engagement member 6.

[0029] The hydraulic cylinder unit is operatively connected to the base element 2 and engages the carrier element 3. When pressure is applied to the hydraulic cylinder unit in a conventional manner, the lifting column 1 extends. The lifting column 1 can be retracted by gravity or (additionally) by applying an appropriate pressure.

[0030] Starting from the lifting column 1 fully contracted as shown in FIG. 4, the hydraulic cylinder unit first moves the carrier element 3 axially upwards along the movement axis FA when the hydraulic cylinder unit engages with the carrier element 3. When the carrier element 3 is extended until the engagement member 6 of the carrier element 3 reaches the upper engagement member 6 of the second intermediate element 5, the engagement member 6 of the carrier element 3 abuts on the upper engagement member 6 of the second intermediate element 5. As a result, the second intermediate element 5 is driven and moved in the direction of the movement axis FA, as is the carrier element 3. When the lifting column 1 is further extended, the lower engagement member 6 of the second intermediate element 5 abuts on the upper engagement member 6 of the first intermediate element 4, as shown in the detailed view of FIG. 3. As a result, the first intermediate element 4 is driven and moved in the direction of the movement axis FA, as is the carrier element 3 and the second intermediate element 5. The lifting column 1 can still be extended until the lower engagement member 6 of the first intermediate element 4 abuts the engagement member 6 of the base element 2. This position of the lifting column 1 is also referred to as the extended position, as shown in FIG.

[0031] When all the engagement members 6 of each outer element are attached to the corresponding engagement members 6 of each inner element, the lifting column 1 can no longer be extended further. The order in which the elements are moved can be arbitrary, for example the first intermediate element 4 can be moved first, then the second intermediate element 5 and finally the carrier element 3.

[0032] Retracting the lifting column 1 works in the opposite manner to extending the lifting column 1 as described above. Figure 5 shows a cross-section of the fully retracted lifting column from Figure 4 along line AA. The lifting column 1 is retracted in the opposite direction until the engaging member 6 of the outer element abuts the engaging member 6 of the inner element.

[0033] Figure 6 shows a detailed view of the area Z of the engagement members 6 in the retracted lifting column 1 from Figure 5. It can be seen that in the retracted position, the engagement members 6 of the respective outer elements abut the engagement members 6 of the respective inner elements from above, whereas in the extended position, the engagement members 6 of the respective outer elements abut the engagement members 6 of the respective inner elements 6 from below, as shown in Figure 3.

[0034] Furthermore, a sliding lining 8 is attached to the first and second intermediate elements 4, 5 as well as to the carrier element 6. The sliding lining may be attached to the inner and / or outer surface of the first and second intermediate elements 4, 5 as well as to the inner surface of the carrier element 6. Furthermore, the sliding lining 8 may be attached to the outer surface of the base element 2. The sliding lining 8 reduces friction between the individual elements when the lifting column 1 is moved. Preferably, a lubricant- and grease-free sliding lining 8 is used for medical devices.

[0035] The engagement members 6 will now be described below with reference to Figures 7 to 9. In this exemplary embodiment, all engagement members 6 are configured identically. However, it is of course possible for the engagement members 6 to be configured differently. For example, since the engagement members 6 of the carrier element 3 carry the maximum weight when the lifting column 1 is fully extended, it may make sense in some circumstances to reinforce these engagement members 6.

[0036] Fig. 7 shows a top view of the engagement member 6. The engagement member 6 has a damping element 9 that dampens the impact when the engagement member 6 abuts. In particular, the damping element 9 is made of plastic. The damping element 9 is preferably made of a first and a second plastic material. The first plastic material has a higher elasticity than the second plastic material. On the other hand, the second plastic material is more rigid than the first plastic material.

[0037] The damping element 9 is preferably a one-piece damping element, i.e. a damping element consisting of only one part. The damping element 9 is manufactured, for example, by means of an injection molding process. The damping element 9 may also be manufactured from a first and a second plastic material in a two-component injection molding process.

[0038] The damping element 9 has an upper elastic part 10 in the direction of the movement axis FA. The damping element 9 further has a lower elastic part 11 in the direction of the movement axis FA. Furthermore, the engagement member 6 has a first end 12 and a second end 13 transversely to the movement axis FA. A rod 14 is formed between the first end 12 and the second end 13 and connects the first end 12 to the second end 13. The upper elastic part 10 and the lower elastic part 11 are separated by the rod 14. The rod 14 prevents deformation of the engagement member 6 transversely to the movement axis FA.

[0039] The upper elastic part 10 and the lower elastic part 11 are made from a first plastic material having a higher elasticity. The rod 14, the first end 12 and the second end 13 are made from a second plastic material having a higher stiffness. As a result, the damping element 9 is elastic in the direction of the axis of movement FA and stiff transversely to the axis of movement FA.

[0040] The damping element 9 further has two upper flexible arms 15, one attached to a first end 12 and the other to a second end 13 in the direction of the movement axis FA. The upper arms 15 surround the upper elastic part 10 such that the upper elastic part 10 is arranged between the rod 14 and the upper arms 15. The upper arms 15 are molded from a second plastic material. The upper arms 15 have a constriction 16 connected to the first end 12. By means of the constriction 16 the upper arms 15 are configured to be bendable and thus allow elastic deformation of the upper elastic part 10.

[0041] The damping element 9 further has two lower flexible arms 17, one attached to the first end 12 and the other to the second end 13, in the direction of the movement axis FA. The lower arms 17 surround the lower elastic part 11 such that the lower elastic part 11 is arranged between the rod 14 and the lower arms 17. The lower arms 17 are molded from a second plastic material. Like the upper arms 15, the lower arms 17 comprise a constriction 16 connected to the first end 12. The constriction 16 allows the lower arms 17 to be bendable and allows elastic deformation of the lower elastic part 10.

[0042] 7, the engagement member 6 has a first plane of symmetry SE1 parallel to the direction of the movement axis FA. The first plane of symmetry SE1 extends through the midline of the rod 14 such that the upper elastic portion 10 is symmetrical to the lower elastic portion 11 and the upper arm portion 15 is symmetrical to the lower arm portion 17. Furthermore, the engagement member 6 has a second plane of symmetry SE2 perpendicular to the direction of the movement axis FA.

[0043] 8 shows a rear view of the engagement member 6. The engagement member 6 has a recess 18 and a protrusion 19 formed in the upper arm portion 15 and the lower arm portion 17. The recess 18 protrudes beyond the protrusion 19. The shape of the recess 18 corresponds to the shape of the protrusion 19.

[0044] As shown in Figures 3 and 6, the projections 19 of the engagement members 6 project inwards from their respective elements and the recesses 18 project outwards. During movement of the lifting column 1, when the engagement members 6 come into abutment, the projections 19 of one engagement member 6 abut against the recesses 18 of the other engagement member 6.

[0045] 9 shows a side view of the engagement members 6. The engagement members 6 have latching claws 20 formed at the first end 12 and the second end 13, respectively. The latching claws 20 engage with the interior of the respective elements and form barbs. This ensures that the engagement members 6 are firmly fixed in the respective passage openings 7. To disengage the engagement members 6, they are elastically deformed by moving the latching claws 20 towards each other, i.e. in the direction of the first plane of symmetry SE1. [Explanation of symbols]

[0046] 1 Hydraulic lifting column 2 Base Elements 3. Career elements 4. First intermediate element 5. Second intermediate element 6 Engagement member 7 Passage opening 8 Slip-resistant lining 9. Damping Elements 10 Upper elastic part 11 Lower elastic part 12 First end 13 Second end 14 bars 15 Upper flexible arm section 16 Stenosis 17 Lower flexible arm section 18 Recess 19 Convex 20 Latch claw

Claims

1. A hydraulic lifting column (1), preferably for a medical device, comprising a hydraulic cylinder unit, a base element (2), a carrier element (3) and at least one intermediate element (4, 5), the hydraulic cylinder unit is configured to move the lifting column (1) along a movement axis (FA) between a retracted position and an extended position; said at least one intermediate element (4, 5) being arranged between said base element (2) and said carrier element (3) at least in said contracted position, the carrier element (3) and the at least one intermediate element (4, 5) are movable relative to the base element (2) along the movement axis (FA) by the hydraulic cylinder unit acting on the carrier element (3), At least one first engagement member (6) is arranged on the carrier element (3) and is formed separately from the carrier element (3); the first engagement member (6) abuts against the intermediate element (4, 5) when the lifting column (1) is moved between the contracted position and the extended position, and drives the at least one intermediate element (4, 5); said first engagement member (6) having a damping element (9), said damping element (9) being preferably made of plastic; the first engagement member (6) has a first end and a second end (12, 13) transverse to the movement axis (FA), and further has a rod (14) connecting the first and second ends (12, 13); A hydraulic lifting column (1), wherein the damping element (9) has elastic parts (10, 11) made from a first plastic material and the rod (14) is made from a second plastic material, the rod (14) separating the elastic parts (10, 11) in the direction of the movement axis (FA) into an upper elastic part and a lower elastic part (10, 11).

2. 2. A hydraulic lifting column (1) according to claim 1, characterized in that it comprises at least one second engagement member (6) arranged on the intermediate element (4, 5) and formed separately from the intermediate element (4, 5), and the first engagement member (6) is configured to abut against the second engagement member (6).

3. 3. A hydraulic lifting column (1) according to claim 1 or 2, characterized in that the damping element (9) is made from the first plastic material and from the second plastic material, the first plastic material having a higher elasticity than the second plastic material.

4. 2. A hydraulic lifting column (1) according to claim 1, characterized in that the damping element (9) is formed as a one-piece piece and manufactured by injection molding.

5. 4. A hydraulic lifting column (1) according to claim 3, characterized in that the damping element (9) is formed as a one-piece piece and manufactured by injection molding.

6. 2. A hydraulic lifting column (1) according to claim 1, characterized in that the damping element (9) is configured to be elastic in the direction of the axis of movement (FA) and to be rigid transversely to the axis of movement (FA).

7. 6. A hydraulic lifting column (1) according to claim 5, characterized in that the damping element (9) is configured to be elastic in the direction of the axis of movement (FA) and to be rigid transversely to the axis of movement (FA).

8. 2. A hydraulic lifting column (1) according to claim 1, characterized in that an upper flexible arm portion (15) is formed at each of the first and second ends (12, 13) in the direction of the movement axis (FA) and surrounds the upper elastic portion (10) so that the upper elastic portion (10) is arranged between the rod (14) and the upper arm portion (15).

9. A hydraulic lifting column (1) according to claim 1 or 7, characterized in that a lower flexible arm portion (17) is formed at each of the first and second ends (12, 13) in the direction of the movement axis (FA) and surrounds the lower elastic portion (11) so that the lower elastic portion (11) is arranged between the rod (14) and the lower arm portion (17).

10. 2. A hydraulic lifting column (1) according to claim 1, characterized in that the first engagement member (6) has a first plane of symmetry (SE1) parallel to the direction of the movement axis (FA) and preferably has a second plane of symmetry (SE2) perpendicular to the direction of the movement axis (FA).

11. 2. A hydraulic lifting column (1) according to claim 1, characterized in that a sliding lining (8) is attached to the carrier element (3) and to the at least one intermediate element (4, 5).

12. A medical device comprising a hydraulic lifting column (1) according to claim 1, 2, 4, 5, 6, 7, 8, 10 or 11.

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