Abstract
The invention relates to an orthopedic device comprising at least one joint and a hydraulic system with at least one valve. The hydraulic system is filled with a hydraulic fluid and the hydraulic fluid contains a silicone oil (2) and an additional oil (4) which has at least one ester group.
Claims
1. An orthopedic device, comprising at least one joint; and a hydraulic system with at least one valve, the hydraulic system being filled with a hydraulic fluid, wherein the hydraulic fluid comprises a silicone oil and an additive oil, wherein the additive oil contains at least one ester group.
2. The orthopedic device according to claim 1, wherein the hydraulic fluid comprises at most 25% additive oil.
3. The orthopedic device according to claim 1, wherein the additive oil contains a glycol ester group and/or a triglyceride group.
4. The orthopedic device according to claim 1, wherein the additive oil comprises at least one bio-oil.
5. A method for filling a hydraulic system for an orthopedic device according to claim 1, comprising initially flushing the hydraulic system with additive oil; and then filling the hydraulic system with silicone oil.
6. The method according to claim 5, wherein during the flushing of the hydraulic system with additive oil, the hydraulic system is initially completely filled with additive oil and the additive oil is then drained again, wherein a proportion of additive oil remains in the hydraulic system.
7. The method according to claim 5, wherein at least some moving parts of the hydraulic system are wetted with the additive oil prior to assembly of the hydraulic system.
8. The method according to claim 5, wherein the additive oil and the silicone oil are introduced into the hydraulic system at different points.
9. The method according to claim 5, wherein the additive oil and the silicone oil are mixed outside of the hydraulic system and then filled into the hydraulic system.
10. The orthopedic device according to claim 1, wherein the hydraulic fluid comprises at most 20% additive oil.
11. The orthopedic device according to claim 1, wherein the hydraulic fluid comprises at most 15% additive oil.
12. The method according to claim 7, wherein all moving parts of the hydraulic system are wetted with the additive oil prior to assembly of the hydraulic system.
13. The method according to claim 9, wherein the additive oil and the silicone oil are gravimetrically mixed outside of the hydraulic system and then filled into the hydraulic system.
Description
[0020] In the following, a number of embodiment examples of the invention will be explained in more detail with the aid of the accompanying figures. FIGS. 1 to 4 show different schematic methods for filling a hydraulic system.
[0021] The method according to FIG. 1 begins with the provision of the silicone oil 2 and of the additive oil 4. The silicone oil and the additive oil are mixed in a mixing step 6, the desired ratio of additive oil to silicone oil being set in the process. The hydraulic system is subsequently filled with the mixed oils.
[0022] FIG. 2 shows a different method. It begins with the provision of the additive oil 4, which is used to flush the hydraulic system in a flushing step 10. Additive oil introduced into the hydraulic system at a first filling point runs, if possible, through the entire hydraulic system and leaves the hydraulic system at a drainage point. If necessary, it is sufficient to flush only parts with the additive oil, for example the metallic components and/or the components that have a metallic surface which at least partially comes into contact with the hydraulic fluid. It is important to note in this method that in the flushing step 10, the additive oil is merely passed through the hydraulic system or a part of the hydraulic system. This is followed by the provision of the silicone oil 2 and the subsequent filling 8, the hydraulic system, which has already been flushed with the additive oil, being filled with the silicone oil during the filling 8. A mixing step 6 is unnecessary with this method. The mixture ratio between the additive oil and the silicone oil, which are inside the hydraulic system upon completion of the method according to FIG. 2, is determined according to the amount of additive oil that remains adhered to the surfaces within the hydraulic system in the flushing step 10 and therefore does not leave the hydraulic system in the flushing step 10. The individual surfaces of the part of the hydraulic system that is flushed with the additive oil in the flushing step 10 remain wetted with the additive oil, so that a certain amount of the additive oil remains within the hydraulic system. During filling 8, the hydraulic system is filled with silicone oil.
[0023] FIG. 3 shows a variation of the method. It does not include a flushing step 10; rather, the hydraulic system is completely filled with the additive oil upon initial filling 8. This is followed by an emptying 12, during which the additive oil introduced into the hydraulic system during initial filling 8 is drained off again. The second filling 8 then occurs, during which the hydraulic system emptied in this way is filled with silicone oil. As in the flushing step 10 according to FIG. 2, a certain amount of the additive oil remains within the hydraulic system upon the first filling 8 and subsequent emptying 12. The surfaces of the hydraulic system that come into contact with the hydraulic fluid remain wetted with the additive oil. The hydraulic system is then filled with silicone oil during the second filling 8.
[0024] FIG. 4 depicts a further embodiment example of the present invention. This method begins with the provision of the additive oil 4. During the subsequent wetting 14, at least some of the moving parts, preferably all moving parts, of the hydraulic system are wetted with the additive oil. This is followed by the assembly 16 of the hydraulic system, during which the wetted moving parts are installed. This also results in a hydraulic system whose surfaces that come into contact with the hydraulic fluid are wetted with additive oil. In the method according to FIG. 4, this is also followed by the filling 8 of the hydraulic system with the silicone oil.
REFERENCE LIST
[0025] 2 provision of the silicone oil [0026] 4 provision of the additive oil [0027] 6 mixing step [0028] 8 filling [0029] 10 flushing step [0030] 12 emptying [0031] 14 wetting [0032] 16 assembly
