Arrangement and method for measuring the flow velocity of an air scavenging process for a thermal coating process of cylinder bores of a cylinder crankcase

Abstract

Arrangement for measuring the flow velocity of an air scavenging process for a thermal coating process of cylinder bores of a cylinder crankcase, comprising a measuring housing (10) having the shape of a cylinder crankcase, which has several cylinder bores (11) corresponding to a cylinder crankcase, and with multiple flow velocity measuring devices (12), wherein each cylinder bore (11) of the measuring housing (10) is assigned at least two flow velocity measuring devices (12), wherein the flow velocity measuring devices (12) are each arranged in a bore (13) provided in the measuring housing (10) such that the flow velocity measuring devices (12) project into the cylinder bore (11) assigned to them, wherein each cylinder bore (11) is assigned two flow velocity measuring devices (12) which project into the cylinder bore (11), characterized in that the two flow velocity measuring devices (12) of a cylinder bore (11) project into the cylinder bore (11) in such a way that the two flow velocity measuring devices (12) are arranged intersecting each other.

Description

[0001] The invention relates to an arrangement for measuring the flow velocity of an air purge for a thermal coating process of cylinder bores of a cylinder crankcase for an internal combustion engine. Furthermore, the invention relates to a method for measuring the flow velocity of an air purge for a thermal coating process of cylinder bores of a cylinder crankcase for an internal combustion engine.

[0002] The cylinder bores, in particular the wall surfaces of the cylinder bores, of a cylinder crankcase are usually coated with a coating material, preferably a metal material. The coating is usually applied using a thermal coating process, such as a plasma spraying process. In order to achieve the best possible, homogeneous coating, the cylinder bores are subjected to negative pressure by means of an extraction system during the coating process, so that an air purge with the atmospheric air is established. This air purge preferably has a flow velocity of 3 to 20 m / s, in particular 8 to 16 m / s, and serves on the one hand to supply atmospheric oxygen to achieve a desired, defined oxide formation in the coating and on the other hand to cool the coating and to remove smoke that must not penetrate the coating.Furthermore, a correctly adjusted air purge influences the uniform coating thickness.

[0003] The air purge flow rate is also called the air settling velocity. The air purge flow rate should remain as constant as possible throughout the entire coating process. To achieve this, the air purge flow rate is adjusted using a measurement.

[0004] It is known to measure the flow velocity of the air purge by hand above and thus outside the cylinder bore using, for example, a vane wheel, a measuring probe or a thermal flow probe. However, manual measurements are not repeatable and therefore the measurement results vary. A person must go into the coating system and carry out and document the measurements there by hand. If the documentation and evaluation of the measured data shows that a correction of the flow velocity of the air purge is necessary, this person must re-enter the coating system after making the correction and take a new measurement. The flow velocity of the air purge must be measured individually for each cylinder bore. The coating system must be shut down during the measurements, which leads to increased downtime of the coating system during the coating process.In addition, measuring by hand is very time-consuming and the risk of measurement errors is greatly increased.

[0005] DE 41 33 277 A1 discloses a device for investigating the flow movement in cylindrical components of reciprocating piston internal combustion engines.

[0006] US 2008 / 0 017 159 A1 describes a masking system for masking a cylinder crankcase of an internal combustion engine during a surface treatment of a cylinder running surface of a cylinder bore of a cylinder of the internal combustion engine.

[0007] WO 97 / 13 153 A1 describes a device with at least one cylindrical sleeve, one axial end of which is covered by the combustion chamber wall in the cylinder head of the engine, with means for generating a gas flow in the sleeve through at least one inlet, with a longitudinal probe guided radially through the sleeve, which is provided with at least two separate internal channels which are connected to the interior of the sleeve via two openings which lie in a plane parallel to the axis of the sleeve and intersect each other and the probe longitudinal axis in this plane, and with a differential pressure gauge, each inlet of which is connected to a corresponding internal channel of the probe.

[0008] US 2001 / 0 022 995 A1 describes a method and a device for thermally coating the cylinder liners of a cylinder block of an internal combustion engine.

[0009] The invention is therefore based on the object of providing an arrangement and a method for measuring a flow velocity of an air purge for a thermal coating process of cylinder bores of a cylinder crankcase, by means of which the measurement can be carried out in a simplified and more accurate manner.

[0010] The object of the invention is achieved by the features of the independent claims. Preferred embodiments and further developments of the invention are specified in the dependent claims.

[0011] The arrangement according to the invention comprises a measuring housing in the shape of a cylinder crankcase, which, corresponding to a cylinder crankcase, has a plurality of cylinder bores. Furthermore, the arrangement comprises a plurality of flow velocity measuring devices, with at least one flow velocity measuring device being assigned to each cylinder bore of the measuring housing. The flow velocity measuring devices are each arranged in a bore formed in the measuring housing such that the flow velocity measuring devices protrude into the cylinder bore assigned to them.

[0012] According to the invention, the measurement of the air purge flow velocity takes place in the measuring housing, which is a detailed replica of a cylinder crankcase, with the measurement taking place directly within this measuring housing. For this purpose, a plurality of bores are provided in the measuring housing, with at least one bore each opening into one of the cylinder bores of the measuring housing, so that each cylinder bore is assigned at least one bore. However, it is also possible for more than one bore to be assigned to each cylinder bore. A flow velocity measuring device is arranged within each of the bores. The flow velocity measuring devices can, for example, be measuring sensors or measuring probes. For example, the flow velocity measuring devices can each be designed as a so-called Prandtl Pitot tube.The flow velocity measuring devices are positioned in the bores in such a way that they extend beyond the bores and into their respective cylinder bores. This ensures that at least one flow velocity measuring device extends into each cylinder bore. Because the flow velocity measuring devices are located directly within the measuring housing, manual measurements outside the cylinder bores and thus outside the measuring housing are no longer necessary. It is also no longer necessary for a person to enter the coating system to perform the measurement. The risk of measurement errors caused by manual measurements can thus be significantly reduced.The positioning of the flow velocity measuring devices within the bores enables very precise positioning of the flow velocity measuring devices, which ensures very accurate measurement results, thus enabling a significantly improved measurement of the air purge flow velocity compared to conventional methods. Furthermore, such an arrangement enables repeatable measurements. Since a person is no longer required to enter the coating system to take the measurement, the downtime of the coating system for measurements during a coating process can also be significantly reduced.In addition, the measuring housing, which is shaped like a cylinder crankcase, allows simultaneous measurement of the air purge flow velocity in all cylinder bores, further reducing the time required for measuring the air purge flow velocity. For example, the measuring housing can be retracted into the coating system between two coating processes of cylinder crankcases to be coated to perform control measurements to determine whether the air purge in the coating system is optimally adjusted.

[0013] The flow velocity measuring devices are preferably positioned such that they extend into the respective cylinder bores along the length of the cylinder bores of the measuring housing, between a first end section and a second end section of the cylinder bores of the measuring housing. The measurement of the air purge flow velocity is thus not carried out at an upper or lower edge of the cylinder bores, but rather within or in an interior space of the cylinder bore defined by the wall surface of the cylinder bore. For example, the flow velocity measuring devices can extend into the cylinder bores approximately midway along the length or the entire length of the cylinder bores. This very central positioning of the flow velocity measuring devices within the respective cylinder bore enables very high measurement accuracy to be achieved.

[0014] Preferably, the flow velocity measuring devices each have two or more measuring ranges. The multiple measuring ranges and the resulting different measuring positions per flow velocity measuring device can increase the measurement accuracy. An average value can be calculated from the individual measuring ranges per flow velocity measuring device, which can be used for evaluation.

[0015] To further increase measurement accuracy, the invention provides two flow velocity measuring devices that extend into the cylinder bore. However, it is also possible for each cylinder bore to be assigned more than two flow velocity measuring devices.

[0016] According to the invention, two flow velocity measuring devices are assigned to each cylinder bore. Thus, the two flow velocity measuring devices of a cylinder bore preferably extend into the cylinder bore in such a way that the two flow velocity measuring devices are arranged in an intersecting manner. This allows the measurement accuracy to be further increased.

[0017] To enable direct evaluation of the data measured by the flow velocity measuring devices, the flow velocity measuring devices are preferably connected to an evaluation unit. The data measured by the flow velocity measuring devices is preferably transferred to the evaluation unit automatically, eliminating the need for manual transfer. Preferably, all flow velocity measuring devices transfer their measured data to one and the same evaluation unit, so that the data measured by the individual flow velocity measuring devices can be consolidated in the evaluation unit and evaluated there together. The data can be transferred to the evaluation unit via cable or wirelessly, for example, via Wi-Fi or Bluetooth.Within the evaluation unit, electronic evaluation of the measured data is possible, so that this no longer has to be done manually by a person.

[0018] The system preferably further comprises a control device by means of which the flow rate of the air purge in the cylinder bores can be individually adjusted. The control device preferably enables automated control of the air purge separately in each individual cylinder bore. Manual adjustment of the air purge flow rate by a person who must enter the coating system prior to adjustment is thus no longer necessary.

[0019] Preferably, this control device is coupled to the evaluation unit in such a way that data from the evaluation unit can be transmitted directly to the control device, and the air purge flow rate in the individual cylinder bores can be adjusted directly based on the data transmitted by the evaluation unit. Coupling the evaluation unit with the control device thus enables automated adjustment of the air purge flow rate in the individual cylinder bores, whereby the evaluated data enables continuous, optimized adjustment of the air purge flow rate.

[0020] The object of the invention is further achieved by means of a method for measuring a flow velocity of an air purge for a thermal coating process of cylinder bores of a cylinder crankcase, in which a measuring housing having the shape of a cylinder crankcase, which has a plurality of cylinder bores corresponding to a cylinder crankcase, is used, and in which bores are introduced into the measuring housing in such a way that at least two of the bores open into each cylinder bore of the measuring housing, and in which a flow velocity measuring device is introduced into each bore, so that at least two flow velocity measuring devices are assigned to each cylinder bore, wherein the flow velocity measuring devices are arranged in the bores in such a way that the flow velocity measuring devices protrude into the cylinder bore assigned to them,wherein each cylinder bore is assigned two flow velocity measuring devices which protrude into the cylinder bore in such a way that the two flow velocity measuring devices are arranged crossing one another.,

[0021] With regard to the advantages and further embodiments of the method according to the invention, reference is made to the above explanations.

[0022] Further measures improving the invention are presented in more detail below with reference to the description of preferred embodiments of the invention with reference to the following figures.

[0023] They show: Fig. 1 a schematic representation of an arrangement with a measuring housing in the form of a cylinder crankcase according to the invention, Fig. 2 a schematic sectional view along a long side of the Fig. 1 shown arrangement according to the invention, Fig. 3 a schematic plan view of the Fig. 2 shown arrangement, Fig. 4 is a schematic sectional view along a longitudinal side of a further arrangement according to the invention, and Fig. 5 a schematic plan view of the Fig. 4 shown arrangement.

[0024] The Fig. 1 to 5 show an arrangement with a measuring housing 10, which has the shape of a cylinder crankcase of an internal combustion engine. The measuring housing 10, like a cylinder crankcase, has a plurality of cylinder bores 11 arranged next to one another, here four cylinder bores 11. During the production of cylinder crankcases 10, the cylinder bores, in particular the wall surfaces of the cylinder bores 11, are provided with a coating. During the thermal coating of the cylinder bores 11, the cylinder bores 11 are subjected to a negative pressure by means of an extraction system so that an air purge with the atmospheric air can occur. This air purge preferably has a flow velocity of 3 to 20 m / s, in particular of 8 to 16 m / s, and serves, on the one hand, to supply atmospheric oxygen to achieve a desired, defined oxide formation in the coating and, on the other hand, to cool the coating.In order to ensure a constant flow velocity of the air purge, a continuous measurement of the flow velocity of the air purge is carried out by means of the measuring housing 10 between the coating processes of the cylinder crankcases by moving the measuring housing 10 into the coating system between the successive coating processes of cylinder crankcases and carrying out the measurement.

[0025] As in Fig. 2 and Fig. As can be seen in Figure 3, four flow velocity measuring devices 12 are positioned in the measuring housing 10, with one flow velocity measuring device 12 being assigned to each cylinder bore 11. For positioning the flow velocity measuring devices 12, four bores 13 are provided in the measuring housing 10, each of which opens into one of the four cylinder bores 11. The flow velocity measuring devices 12 are positioned within the bores 13 such that the flow velocity measuring devices 12 protrude into the cylinder bore 11 assigned to them.

[0026] As in Fig. As can be seen in Figure 3, the flow velocity measuring devices 12 extend so far into the cylinder bores 11 that they extend beyond the center of the cylinder bores 11. The flow velocity measuring devices 12 extending into the cylinder bores 11 extend within the cylinder bores 11 perpendicular to the longitudinal extent of the cylinder bores 11.

[0027] As in Fig. 2, the flow velocity measuring devices 12 are each positioned such that they protrude into the respective cylinder bore 11 along the length L of the cylinder bores 11 between a first end section 14 and an opposite second end section 15 of the cylinder bores 11. The measurement of the flow velocity of the air purge is therefore not carried out at an upper or lower edge of the cylinder bores 11, but rather within or in an interior of the cylinder bore 11 delimited by the wall surface of the cylinder bore 11. In the embodiment shown here, the flow velocity measuring devices 12 protrude into the cylinder bores 11 approximately in the middle of the length L or the total length of the cylinder bores 11.

[0028] All flow velocity measuring devices 12 are connected to an evaluation unit 16, as shown in Fig. 3. The connection is shown in dashed lines here, which means that the connection can be made via cable or wirelessly, for example via WLAN or Bluetooth. The data measured by the flow velocity measuring devices 12 can be transmitted automatically to the evaluation unit 16, so that manual data transmission no longer has to be carried out. In the embodiment shown here, all flow velocity measuring devices 12 transmit their measured data to one and the same evaluation unit 16, so that the data measured by the individual flow velocity measuring devices 12 can be bundled in the evaluation unit 16 and evaluated there together. However, it is also possible for each flow velocity measuring device 12 to be assigned an evaluation unit 16.The data from the individual evaluation units 16 can then be bundled in another unit, for example a master computer.

[0029] The evaluation unit 16 is in turn connected to a control device 17. The connection between the evaluation unit 16 and the control device 17 can also be established by cable or wirelessly, via WLAN or Bluetooth. The flow rate of the air purge in the cylinder bores 11 can be adjusted individually using the control device 17. However, it is also possible for the flow rate of the air purge in several or all cylinder bores 11 to be adjusted simultaneously using the control device 17. The control device 17 is coupled to the evaluation unit 16 in such a way that data from the evaluation unit 16 can be transmitted directly to the control device 17, and the flow rate of the air purge in the individual cylinder bores 11 can be adjusted directly based on the data transmitted by the evaluation unit 16.By coupling the evaluation unit 16 with the control device 17, an automated adjustment of the flow velocity of the air purge in the individual cylinder bores 11 is possible, whereby a continuous, optimized, fully automated adjustment of the flow velocity of the air purge can be made possible on the basis of the evaluated data.

[0030] In Fig. 4 and Fig. 5 shows an embodiment of an arrangement in which two flow velocity measuring devices 12 are assigned to each cylinder bore 11 of the measuring housing 10. Otherwise, the arrangement shown in the Fig. 4 and Fig. 5 shown arrangement of the Fig. 2 and Fig. 3 shown arrangement.

[0031] At the Fig. 4 and Fig. In the embodiment shown in Figure 5, eight flow velocity measuring devices 12 are provided, with two of the eight flow velocity measuring devices 12 being assigned to each cylinder bore 11. Thus, eight bores 13 are also provided in the measuring housing 10, with two bores 13 each opening into a cylinder bore 11 of the measuring housing 10.

[0032] As in Fig. 5, in this embodiment, the flow velocity measuring devices 12 protrude into the cylinder bores 11 in such a way that the two flow velocity measuring devices 12 assigned to a cylinder bore 11 intersect within the cylinder bore 11. Here, too, the flow velocity measuring devices 12 protrude so far into the cylinder bores 11 that they extend beyond the center of the cylinder bores 11. The flow velocity measuring devices 12 protruding into the cylinder bores 11 run within the cylinder bores 11 perpendicular to the longitudinal extent of the cylinder bores 11.

[0033] As in Fig. 4, the flow velocity measuring devices 12 are each positioned such that they protrude into the respective cylinder bore 11 along the length L of the cylinder bores 11 between a first end section 14 and an opposite second end section 15 of the cylinder bores 11. The measurement of the flow velocity of the air purge is therefore not carried out at an upper or lower edge of the cylinder bores 11, but rather within or in an interior space of the cylinder bore 11 delimited by the wall surface of the cylinder bore 11. In the embodiment shown here, the flow velocity measuring devices 12 protrude into the cylinder bores 11 approximately in the middle of the length L or the total length of the cylinder bores 11.

[0034] Also in the Fig. 4 and Fig.In the embodiment shown in Figure 5, the flow velocity measuring devices 12 are connected to an evaluation unit 16, wherein the evaluation unit 16 is in turn connected to a control device 17.

[0035] The flow velocity of the air purge is measured using the measuring housing 10 within the coating system when no cylinder crankcase is currently being coated. For example, it is useful to measure it at the beginning of a daily shift and then possibly again in the middle of a daily shift.

[0036] The invention is not limited in its implementation to the preferred embodiments described above. Rather, a number of variants are conceivable, which utilize the solutions presented even in fundamentally different embodiments. All features and / or advantages arising from the claims, the description, or the drawings, including design details of spatial arrangements and method steps, may be essential to the invention both individually and in a wide variety of combinations. List of reference symbols 10 measuring housings 11 Cylinder bore 12 Flow velocity measuring device 13 Hole 14 First final section 15 Second final section 16 Evaluation unit 17 Control device L Length of cylinder bore

Claims

[1] Arrangement for measuring a flow velocity of an air purge for a thermal coating process of cylinder bores of a cylinder crankcase, with a measuring housing (10) in the shape of a cylinder crankcase, which has a plurality of cylinder bores (11) corresponding to a cylinder crankcase, and with several flow velocity measuring devices (12), wherein each cylinder bore (11) of the measuring housing (10) is assigned at least two flow velocity measuring devices (12), wherein the flow velocity measuring devices (12) are each arranged in a bore (13) provided in the measuring housing (10) in such a way that the flow velocity measuring devices (12) project into the cylinder bore (11) assigned to them, wherein each cylinder bore (11) is assigned two flow velocity measuring devices (12) which project into the cylinder bore (11), characterized by that the two flow velocity measuring devices (12) of a cylinder bore (11) protrude into the cylinder bore (11) in such a way that the two flow velocity measuring devices (12) are arranged crossing one another. [2] Arrangement according to claim 1, characterized by that the flow velocity measuring devices (12) are each positioned such that they project into the respective cylinder bore (11) along the length of the cylinder bores (11) between a first end section (14) and a second end section (15) of the cylinder bores (11). [3] Arrangement according to claim 1 or 2, characterized by that the flow velocity measuring devices (12) each have two or more measuring ranges. [4] Arrangement according to one of claims 1 to 3, characterized by that the flow velocity measuring devices (12) are connected to an evaluation unit (16). [5] Arrangement according to one of claims 1 to 4, characterized by that a control device (17) is provided by means of which the flow velocity of the air purge in the cylinder bores (11) can be individually adjusted. [6] Arrangement according to claim 5, characterized by that the control device (17) is coupled to the evaluation unit (16) in such a way that data from the evaluation unit (16) can be transmitted directly to the control device (17) and the flow velocity of the air purge in the individual cylinder bores (11) is adjusted directly on the basis of the data transmitted by the evaluation unit (16). [7] A method for measuring a flow velocity of an air purge for a thermal coating process of cylinder bores of a cylinder crankcase, in which a measuring housing (10) having the shape of a cylinder crankcase and having a plurality of cylinder bores (11) corresponding to a cylinder crankcase is used, and in which bores (13) are introduced into the measuring housing (10) in such a way that at least two of the bores (13) open into each cylinder bore (11), and in which a flow velocity measuring device (12) is introduced into each bore (13) in such a way that at least two flow velocity measuring devices (12) are assigned to each cylinder bore (11), wherein the flow velocity measuring devices (12) are arranged in the bores (13) in such a way that the flow velocity measuring devices (12) project into the cylinder bore (11) assigned to them,wherein each cylinder bore (11) is assigned two flow velocity measuring devices (12) which protrude into the cylinder bore (11) in such a way that the two flow velocity measuring devices (12) are arranged crossing one another.,

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