LUBRICATION SYSTEM AND METHOD

Abstract

A lubrication system (1) for lubricating lubrication points (2-1 to 2-8). The lubrication system includes a lubricant reservoir (4), lubricant injectors (6-1 to 6-8) for providing lubricant from the lubricant reservoir to the lubrication points, and a control unit (8) for controlling the flow of lubricant from the lubricant reservoir to the lubricant injectors. The control unit controls the lubricant injectors to simultaneously deliver lubricant to the lubrication points in predefined lubrication cycles (C.sub.L). The lubrication system also includes a condition monitoring unit (10) for monitoring the condition of the lubrication points. When the condition monitoring unit determines the condition of at least one of the lubrication points is abnormal, the control unit controls the lubricant injector being associated with the lubrication point having the abnormal condition to individually deliver an additional dose of lubricant to the associated lubrication point.

Claims

1. A lubrication system for lubricating a plurality of lubrication points, the lubrication system comprising: a lubricant reservoir; a plurality of lubricant injectors for providing lubricant from the lubricant reservoir to the plurality of lubrication points; a control unit for controlling the flow of lubricant from the lubricant reservoir to the plurality of lubricant injectors, the control unit being configured to control the plurality of lubricant injectors to simultaneously deliver lubricant to the plurality of lubrication points in predefined lubrication cycles); and a condition monitoring unit for monitoring the condition of the plurality of lubrication points, the condition monitoring unit being configured to determine when the condition of at least one of the plurality of lubrication points is abnormal, the control unit being configured to control the lubricant injector associated with said one lubrication point having an abnormal condition to individually deliver an additional dose of lubricant to the corresponding said one lubrication point when the condition monitoring unit determines the condition of said one lubrication point is abnormal.

2. The lubrication system according to claim 1, wherein the control unit is configured to deliver the additional dose of lubricant to the lubrication point having the abnormal condition outside the predefined lubrication cycles.

3. The lubrication system according to claim 1, wherein the condition monitoring unit comprises at least one sensor for each bearing of the plurality of lubrication points, wherein the at least one sensor is configured to monitor at least one parameter of the respective lubrication point being indicative for an abnormal condition of the lubrication point.

4. The lubrication system according to claim 3, wherein the lubrication point is a bearing and wherein the at least one parameter includes temperature and/or vibration of the bearing.

5. The lubrication system according to claim 3, wherein the condition monitoring unit is configured to compare the value of the monitored parameter with a predefined threshold and is configured to determine that the condition of the respective lubrication point is abnormal when the value of the monitored parameter exceeds the predefined threshold.

6. The lubrication system according to claim 1, wherein the condition monitoring unit is configured to monitor the plurality of lubrication points continuously.

7. The lubrication system according to claim 1, wherein the control unit is configured to individually control each of the plurality of lubricant injectors to stop the transport of lubricant to the plurality of lubrication points outside the predefined lubrication cycles and to deliver an additional dose of lubricant to the lubrication point having an abnormal condition if required.

8. The lubrication system according to claim 7, wherein each of the plurality of lubricant injectors comprises a valve which is configured to be closed or opened by the control unit.

9. The lubrication system according to claim 1, wherein the control unit is configured to adjust the predefined lubrication cycles when the control unit determines over a predetermined time period that all lubrication points of the plurality of lubrication points require additional doses of lubricant outside the predefined lubrication cycle.

10. The lubrication system according to claim 2, wherein the condition monitoring unit comprises at least one sensor for each bearing of the plurality of lubrication points, wherein the at least one sensor is configured to monitor at least one parameter of the respective lubrication point being indicative for an abnormal condition of the lubrication point.

11. The lubrication system according to claim 10, wherein the lubrication point is a bearing and wherein the at least one parameter includes temperature and/or vibration of the bearing.

12. The lubrication system according to claim 11, wherein the condition monitoring unit is configured to compare the value of the monitored parameter with a predefined threshold and is configured to determine that the condition of the respective lubrication point is abnormal when the value of the monitored parameter exceeds the predefined threshold.

13. The lubrication system according to claim 12, wherein the condition monitoring unit is configured to monitor the plurality of lubrication points continuously.

14. The lubrication system according to claim 13, wherein the control unit is configured to individually control each of the plurality of lubricant injectors to stop the transport of lubricant to the plurality of lubrication points outside the predefined lubrication cycles and to deliver an additional dose of lubricant to the lubrication point having an abnormal condition if required.

15. The lubrication system according to claim 14, wherein each of the plurality of lubricant injectors comprises a valve which is configured to be closed or opened by the control unit.

16. The lubrication system according to claim 15, wherein the control unit is configured to adjust the predefined lubrication cycles when the control unit determines over a predetermined time period that all lubrication points of the plurality of lubrication points require additional doses of lubricant outside the predefined lubrication cycle.

17. A lubrication method for lubricating a plurality of lubrication points, the method comprising: controlling a plurality of lubricant injectors to deliver lubricant from a lubricant reservoir to a plurality of lubrication points in predefined lubrication cycles; monitoring the condition of the plurality of lubrication points, and, when it is determined that the condition of at least one of the plurality of lubrication points is abnormal, controlling the lubricant injector being associated with the at least one of the plurality of lubrication points to deliver an additional dose of lubricant to the at least one of the plurality of lubrication points.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In the following, preferred embodiments of the present disclosure are described in relation to the drawings, wherein the drawings are exemplarily only, and are not intended to limit the scope of protection. The scope of protection is defined by the accompanied claims, only.

[0022] The figures show:

[0023] FIG. 1: a schematic view of a lubrication system; and

[0024] FIG. 2: a diagram illustrating the lubrication cycles of the lubrication system of FIG. 1.

DETAILED DESCRIPTION

[0025] In the following same or similar functioning elements are indicated with the same reference numerals.

[0026] FIG. 1 shows a lubrication system 1. The lubrication system 1 is configured to lubricate a plurality of lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. The lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 may be for example bearings. In FIG. 1, the bearings are shown as ball bearings but may also be any other kind of bearing, for example any other kind of rolling bearings like roller or angular contact ball bearings or plain bearings without any rolling elements.

[0027] The lubrication system 1 comprises a lubricant reservoir 4 which may be combined with a pressure valve, forming a pump unit. The lubrication reservoir 4 comprises a lubricant like oil or grease. Further, the lubrication system 1 comprises a plurality of lubricant injectors 6-1, 6-2, 6-3, 6-4, 6-5, 6-6, 6-7, 6-8, which are configured to provide lubricant from the pump unit 4 to the plurality of lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. The flow of lubricant is controlled by a control unit 8. Particularly, the control unit 8 is configured to control the plurality of lubricant injectors 6-1, 6-2, 6-3, 6-4, 6-5, 6-6, 6-7, 6-8 to simultaneously deliver lubricant to the plurality of lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8) in predefined lubrication cycles (C.sub.L, shown in FIG. 2 and explained below in further detail). The delivery of lubricant in predefined lubrication cycles implements an automatic and centralized lubrication of the lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. The predefined lubrication cycles may be defined beforehand based on application considerations, like the typical amount of lubricant and intervals the lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 will require re-lubrication.

[0028] In addition, the lubrication system 1 further comprises a condition monitoring unit 10 for monitoring the condition of the plurality of lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. The condition monitoring unit 10 may comprise a plurality of sensors 12-1, 12-2, 12-3, 12-4, 12-5, 12-6, 12-7, 12-8 which are able to measure at least one parameter of each of the lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. The parameters may be any kind of parameter being suitable for assessing the lubrication point condition or state of the respective lubrication point 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8.

[0029] The condition monitoring unit 10 may determine, for example based on the measured parameters, that the condition of at least one of the plurality of lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 is abnormal. This may be the case for example when the temperature as the measured parameter exceeds a predefined threshold.

[0030] In case one or more of the lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 is determined as to be abnormal, the control unit 8 is configured to control the lubricant injector 6-1, 6-2, 6-3, 6-4, 6-5, 6-6, 6-7, 6-8 being associated with the lubrication point or points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 being in the abnormal state or condition to individually deliver an additional dose of lubricant to the associated lubrication point or points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8.

[0031] The lubrication system 1 may use a close to real-time monitoring for assessing the lubrication condition of the lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. The assessment may be based on one or more parameters like vibration, temperature, ultrasound, or the like, as described above. When an abnormal condition associated with one of the lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 is detected, the control unit 8 will trigger an extra lubricant dose to the specific lubrication point/bearing 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8, without modifying its standard lubrication cycle.

[0032] Further, after each extra lubrication dose, the control unit 8 may re-assess the lubrication condition of the re-lubricated lubrication point 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 to determine if another extra lubrication dose is required. The lubrication system 1 can be configured to have a predetermined number of extra lubricant doses or to continue lubricating until the abnormal condition is cleared by the lubrication system 1. Further, all other lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 may also be constantly monitored and re-lubricated when necessary.

[0033] The lubrication system 1 may store the lubrication point condition(s) and system operational conditions for post-processing, trending, and analysis. For example, for the purpose to adjust the predefined lubrication cycles when necessary.

[0034] In this context it should be noted that the injectors 6-1, 6-2, 6-3, 6-4, 6-5, 6-6, 6-7, 6-8 each can provide a predefined amount or dose of lubricant. Further, a pump (not shown) may be used for supplying the lubricant from the pump unit 4 to the injectors 6-1, 6-2, 6-3, 6-4, 6-5, 6-6, 6-7, 6-8. Each of the injectors 6-1, 6-2, 6-3, 6-4, 6-5, 6-6, 6-7, 6-8 may have a valve, for example a solenoid to allow or prevent lubricant flow from the injector 6-1, 6-2, 6-3, 6-4, 6-5, 6-6, 6-7, 6-8 to the lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8.

[0035] FIG. 2 shows a diagram illustrating a lubrication cycle C.sub.L, where the x axis corresponds to the time and the y axis corresponds to the amount of delivered lubricant (0 means no lubricant is delivered and 1 means that a predefined amount or dose of lubricant is delivered). As can be seen in FIG. 2, the lubrication system 1 is an automatic lubrication system which runs a standard lubrication cycle C.sub.L (having a run time t.sub.P during which lubricant is delivered to all lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 and a pause time t.sub.P during which no lubricant is delivered). When the control unit 8 of the lubrication system 1 receives condition monitoring signals via the condition monitoring unit 10 and the sensors 12-1, 12-2, 12-3, 12-4, 12-5, 12-6, 12-7, 12-8 which indicate that a specific lubrication point 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 needs additional lubrication, a selective lubrication may be carried out as explained above. Selective lubrication means that the control unit 8 reacts by providing an additional lubrication dose which is isolated to only the lubrication point(s) 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 which need(s) additional lubrication. This additional lubrication occurs at a time t.sub.Extra during the regularly scheduled pause time t.sub.P for the rest of the lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. At the same time, it does not alter the standard lubrication cycle C.sub.L.

[0036] In the following, an example sequence of lubrication steps is described. During normal operation, the control unit 8 runs a typical lubrication cycle C.sub.L. (standard lubrication cycle), which consists of an amount of the expected run time t.sub.R and a typically much longer pause time t.sub.P. The control unit 8 completes this cycle continuously to deliver grease to all lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. When an abnormal under-lubrication condition is detected, this condition (alarm status) of only the affected bearing or lubrication point 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 is communicated to the control unit 8. During the pause time t.sub.P of the standard cycle C.sub.L, the control unit 8 closes all injector valves except for the affected lubrication point or points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 and initiates an extra lubrication dose for the affected lubrication point or points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8. The extra lubrication t.sub.Extra is completed inside of the overall pause time t.sub.P. When the overall pause time t.sub.P is over and the run time t.sub.P begins, all lubrication points 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 will be lubricated. This extra lubrication can continue through multiple lubrication cycle time intervals C.sub.L if the under-lubrication condition persists. In practice, it is typically only necessary for 1-2 extra lubrications during normal operation. When a bearing or lubrication point 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8 is damaged, a long-term demand for extra lubrication may be expected and these may be programmed via the control unit 8.

[0037] In summary, the herein described lubrication system provides an improved lubrication of different kind of lubrication points, for example bearings, by a combination of an automatic, centralized lubrication at predetermined lubrication cycles and an additional lubrication at specific, individual lubrication times for lubrication points requiring an additional lubrication. The lubrication system successfully combines predictive maintenance with lubrication automation, resulting in a lubrication system that modifies its cycle according to the bearing or lubrication point condition.

[0038] The lubrication system may be particularly suitable for critical applications, helping to avoid unscheduled machine shutdowns caused by lubrication system issues and bearing faults. As additional lubricant is provided when specific monitoring parameter levels surpass alert thresholds, the extra lubrication can help to slow down the degradation of the respective bearings or lubrication points. The automation of additional lubrication makes manual intervention unnecessary and contributes to worker safety. Critical asset runnability may be extended and/or unplanned shutdown may be eliminated due to the ability of the automatic extra lubrication when necessary. Further, as the additional lubricant is only delivered to lubrication points which require the additional lubrication, the overall lubricant consumption may be reduced (when compared to manual lubrication) because it adds more lubricant only after confirmation that more lubricant is needed and preferably only lubricates the point that requires it and not all the injectors connected to the same line.

REFERENCE NUMERALS

[0039] 1 Lubrication system [0040] 2-1 to 2-8 bearing/lubrication point [0041] 4 lubricant reservoir/pump unit consisting of a reservoir and a pressure valve [0042] 6-1 to 6-8 lubricant injector [0043] 8 control unit [0044] 10 condition monitoring unit [0045] 12-1 to 12-8 sensor [0046] C.sub.L lubrication cycle [0047] t.sub.P pause time [0048] t.sub.R run time [0049] t.sub.Extra additional lubrication time