Pressure equalizing element and method for mounting such pressure equalizing element

Abstract

The invention relates to a pressure-equalizing element for attachment to a surface of a housing or other object provided with a pressure-equalizing opening, comprising:-a first film (2), which is designed to have a first surface (3) for attachment to the surface of the housing, and-a second film (4), which is designed to have a second surface (5) for attachment to the surface of the housing, the first film (2) has a first surface (3), a second film (4) which is connected to the first film at least in sections on a second surface (5) of the first film opposite the first surface (3), and a diaphragm (6) which is geometrically arranged between the first film (2) and the second film (4) on the second surface (5) of the first film (2), the first film (2) having a pressure equalization recess (7), the pressure-equalizing element (1) has a pressure-equalizing recess (9) which is covered by the diaphragm (6), characterized in that the pressure-equalizing element (1) is received on a carrier membrane (8) by means of the first surface (3) of the first membrane (2) before being mounted on the surface of the housing, and in that the carrier membrane (8) can be removed from the first surface (3) for mounting, and in that the carrier membrane (8) has at least one test recess (9), and the test recess (9) and the pressure equalization recess (7) overlap at least in some regions.

Description

Field of the Invention

[0001] The present invention relates to a pressure equalizing element and a method for installing such a pressure equalizing element. A pressure equalizing label for pasting on a surface and a method for manufacturing such a pressure equalizing element are known from DE102014105193A1. Background Art

[0002] The use of the pressure equalizing element on a motor vehicle drive unit is described below, which should not be construed as a limitation of the present invention to such an application. During manufacture, the pressure equalizing element with a diaphragm is applied to a carrier film, wherein the diaphragm is air and moisture impermeable at least in one direction, and the carrier film together with the pressure equalizing element is wound into a film roll. The film roll is placed in an automatic dispenser (Spenderautomat) in the manufacturing device. The automatic dispenser separates the pressure equalizing elements and places them such that a manipulator can receive a single pressure equalizing element and then apply the single pressure equalizing element to an interface provided for pressure equalization on the drive unit.

[0003] Furthermore, subsequently, i.e., after the pressure equalizing element is applied to the interface, a flow test device is applied to the pressure equalizing element and a negative pressure is applied to the pressure equalizing element using the pressure equalizing element. An air flow through the pressure equalizing element is generated by the negative pressure, and this air flow can be measured and compared with a rated value. When the pressure equalizing element is applied to the interface on the drive unit, the pressure equalizing element can elastically deform, wherein the pressure equalizing element or a part of the pressure equalizing element returns to its initial state after the elastic deformation, which may take a relatively long time. However, this elastic deformation results in a change in the possible air flow through the pressure equalizing element. In other words, the pressure equalizing element shows different flow values immediately after being applied to the interface compared to a relatively long time after the application. In this context, it is known to establish a correlation between the measurement immediately after the application and the measurement after a relatively long time, or to perform a long-term measurement of the air flow only after a relatively long time. In the first alternative (measuring immediately after applying the pressure equalizing element), the air flow for the intended operation is not measured. In the case of measuring the air flow after a relatively long time, it is necessary to wait for the relatively long time after applying the pressure equalizing element until the air flow is measured, i.e., a delay time in the manufacture results in the second alternative. Summary of the Invention

[0004] The present invention provides an improved pressure equalizing element and a method for installing the pressure equalizing element. This task is solved by a pressure equalizing element according to the first claim or by a method for installing the pressure equalizing element. Preferred further improvements of the present invention are the subject matters of the dependent claims respectively.

[0005] In the context of the present invention, the pressure equalizing element can be understood as a device that can achieve pressure equalization between the interior space and the environment adjacent to the interior space by means of an air flow, wherein the air flow passes through the pressure equalizing element, and foreign matter, especially moisture and particles, is prevented or at least hindered from entering uncontrolled through the pressure equalizing element. Such pressure equalizing elements are known in different structural forms, especially in the structural form of a drive device (such as a transmission), and then as so-called transmission exhaust machines. Here, the present invention studies a pressure equalizing element for pasting onto the surface of a housing or other object provided with a pressure equalizing opening, and such a pressure equalizing element is also called a pressure equalizing label because it can be pasted onto the surface similar to a label in particular. The pressure equalizing element covers the opening in the housing in its installed or pasted state, so that the air flow passes through the pressure equalizing element and flows out of or into the housing. Generally, a device for pressure equalization using a plurality of such pressure equalizing elements can be provided, so that for example, only the inflowing or only the outflowing or only a partial air flow passes through a single such pressure equalizing element, or only a single such pressure equalizing element is provided, and thus both the inflowing and outflowing air flows pass through such a pressure equalizing element.

[0006] The proposed pressure equalizing element consists of a plurality of layers, where such a layer can have a film as a component or can be composed of a film. Here, the film can be understood in this sense and also generally as a thin-layer component. The pressure equalizing element having a film as a component is basically known from the prior art, especially from the above-mentioned DE102014105193A1.

[0007] The proposed pressure equalizing element has a first film as a component, wherein the first film is designed to have a first surface for pasting onto the surface of a housing, especially the surface of a component. Thus, the pressure equalizing element can be directly pasted onto the component surface using the first surface of the first film. Preferably, the first surface has an adhesive or adherent layer, which is designed to form a material-locking connection with the component surface during the installation of the pressure equalizing element.

[0008] Furthermore, the pressure equalizing element has a second membrane as a component part, wherein the second membrane is at least partially connected, preferably materially locked, to the first membrane on a second surface of the first membrane opposite the first surface. Figuratively speaking, the first membrane and the second membrane are connected to each other in a planar manner with respect to their geometric structures and are superimposed on each other. Furthermore, the first membrane and the second membrane are designed geometrically differently and are not connected to each other over the entire surface, so that at least one ventilation channel is formed between the two membranes, and the ventilation channel can achieve exhaust or ventilation air flow, so-called pressure equalizing air flow, during the planned operation of the pressure equalizing element.

[0009] Furthermore, the pressure equalizing element has a diaphragm which is geometrically arranged between the first membrane and the second membrane and is thus also arranged on the second surface of the first membrane. Further preferably, the second membrane is arranged at a distance from the diaphragm such that the air flow through the diaphragm can pass through this gap. The diaphragm is functionally constructed such that a pressure equalizing flow occurs through the diaphragm, and this pressure equalizing flow can achieve pressure equalization during the planned operation of the pressure equalizing element. Furthermore, the first membrane has pressure equalizing notches, in particular in order to enable such a pressure equalizing flow, and the diaphragm covers the pressure equalizing notches. In particular, during the planned operation of the pressure equalizing element, the diaphragm is positioned by means of the first membrane.

[0010] The present invention relates to an embodiment of a pressure equalizing element before its installation for planned operation, wherein in this state, the pressure equalizing element is received on a carrier film by means of the first surface of the first membrane before being installed on the surface of a housing, and the carrier film can be removed from the first surface for installation and is removed from the first surface during installation. Furthermore, the carrier film has a test notch, and the test notch is arranged in the carrier film such that the test notch in the carrier film and the pressure equalizing notch in the first membrane overlap at least partially and preferably completely. In particular, in this embodiment of the present invention, a test air flow can already be guided through the diaphragm before the diaphragm is assembled as planned, because the diaphragm is not completely covered by the carrier film and can thus enable a functional test of the pressure equalizing element before the pressure equalizing element is assembled as planned and can thus prevent or at least reduce the probability of installing a pressure equalizing element that does not work properly. Different from traditional pressure equalizing elements, in traditional pressure equalizing elements, a functional test can only be achieved after their installation, and thus there is a risk in traditional pressure equalizing elements that if the pressure equalizing element is malfunctioning, a malfunctioning pressure equalizing element is installed, while with the pressure equalizing element according to the present invention, the test can be achieved immediately before installing the pressure equalizing element and thus the possible necessary rework can be reduced.

[0011] In a preferred embodiment of the pressure equalizing element, the carrier film has a plurality of test notches, wherein at least two of these test notches or these test notches are separated from each other by a carrier film tab or by a plurality of carrier film tabs. The test notches can have any geometry, and the carrier film tabs are thus formed by material regions of the carrier film between these test notches. Furthermore, it is proposed that at least one or more of the test notches overlap at least partially or completely with the pressure equalizing notches in the first film. In particular, such an overlap results in a fluid-guided connection through the carrier film to the diaphragm, and thus, in the case where the carrier film is applied, i.e., before the pressure equalizing element is installed as planned, a functional test of the pressure equalizing element can be achieved. Furthermore, it is proposed that at least one of the carrier film tabs at least partially covers the test notches in the first film. In particular, such a covering of the diaphragm by the carrier film tab provides mechanical protection for the diaphragm, and in particular, the pressure equalizing element received on the carrier film can be reliably transported or operated by such protection of the pressure equalizing element.

[0012] In a preferred embodiment of the present invention, the carrier film has at least one test notch, and the at least one test notch and the pressure equalizing notch are arranged to coincide with each other. Preferably, the pressure equalizing notch in the first film is completely located within the test notch in the carrier film, so that an unobstructed flow of the pressure equalizing notch through the test notch relative to the diaphragm can be achieved. In particular, in the sense of the present invention, such an arrangement structure in which the pressure equalizing notch is completely inside the test notch can also be understood as being coincident in this sense. In particular, in the case of a coincident orientation, a simple test of the flow through the diaphragm can be achieved.

[0013] Furthermore, a method for installing the pressure equalizing element in one of the aforementioned embodiments before installation is also proposed, and this method has at least the following steps:

[0014] - Receiving the pressure equalizing element with the carrier film in a test device,

[0015] - Applying a pressure difference between the side of the pressure equalizing element on which the carrier film is arranged and the side of the pressure equalizing element opposite to this side, so that a test air flow through the pressure equalizing element occurs due to this pressure difference,

[0016] - Evaluating the pressure equalizing element by means of the test air flow,

[0017] - Removing the carrier film from the first surface of the first film,

[0018] - Installing the pressure equalizing element on the surface of the housing.

[0019] In this method, it is possible to test the pressure equalizing element before installing the pressure equalizing element involved, and thus the probability of installing a pressure equalizing element that does not work properly or does not work fully properly can be reduced. Preferably, the test device has a suction hood or a pressure hood, which is connected to the pressure equalizing element in order to generate a pressure difference for causing a test air flow.

[0020] In a preferred embodiment of the method for installing a pressure equalizing element of the described structural type, in order to evaluate the pressure equalizing element, in particular whether the pressure equalizing element is suitable (normal (iO) state) or not suitable (abnormal (niO) state) for installation, the test air flow is detected indirectly or directly. Here, the detection is particularly understood as the measurement of the test air flow or preferably the measurement of the pressure difference. In addition, the detected test air flow or the value detected for the test air flow is compared with a rated test air flow. Such a rated test flow can in particular be a theoretically or experimentally determined rated value or rated range, by means of which the functionality of the tested pressure equalizing element can be evaluated. Description of the Drawings

[0021] Next, the various features and embodiments of the present invention will be described in detail with the aid of at least partially schematic diagrams. Here, there may also be other features different from the features shown in combination. In the drawings:

[0022] Figure 1 A sectional view of a pressure equalizing element having a pressure equalizing opening for pasting onto a carrier film is shown.

[0023] Figure 2 A top view of a carrier film having a plurality of test notches is shown. Detailed Description of the Invention

[0024] In Figure 1 a pressure equalizing element 1 for pasting onto a housing is shown, wherein the housing is provided with a pressure equalizing opening. The pressure equalizing element 1 has a first film 2. The first film 2 has a first surface 3 for pasting onto the surface of the housing. In addition, the pressure equalizing element 1 has a second film 4, which is arranged on a second surface 5 of the first film 2 opposite to the first surface 3. The second film 2 is connected to the first film 2 sectionally on the second surface 5. Geometrically, a diaphragm 6 is arranged between the first film and the second film, and the diaphragm is arranged on the second surface 5 of the first film 2. The first film 2 has a pressure equalizing notch 7, which is covered by the diaphragm 6.

[0025] The pressure equalizing element 1 is shown in its state before it is mounted on the surface of the housing. Thus, the pressure equalizing element is received on the carrier film 8 by means of a first film 2 having its first surface 3. The carrier film 8 can be understood as a protective film for the adhesive coating on the first surface 3. In addition, the carrier film 8 can be removed from the first surface 3 for installation, figuratively speaking, the carrier film 8 is peeled off from the first surface 3 and thus the adhesive coating is exposed. When pasting, i.e., when the pressure equalizing element is mounted on the housing, the pressure equalizing element is pressed, which can lead to a temporary change in the function of the diaphragm 6, whereby the then functional test of the pressure equalizing element becomes difficult after its installation.

[0026] In the illustrated embodiment, the carrier film 8 has a test notch 9, wherein the test notch 9 is configured and the carrier film 8 is arranged on the first surface such that the test notch 9 and the pressure equalizing notch 7 overlap and are superposed on one another.

[0027] By this design of the pressure equalizing element 1 and the carrier film 8, the pressure equalizing element is received on the carrier film. When the carrier film 8 is still arranged on the pressure equalizing element 1, a test air flow 11 through the diaphragm 6 can be generated by means of a corresponding pressure difference, or in other words, it is thus possible to carry out a functional test of the pressure equalizing element shortly before the installation of the pressure equalizing element, and a malfunctioning equalizing element 1 is not fed into production at all.

[0028] In Figure 2 a view of the carrier film 8 shows an embodiment of the invention. In this embodiment, the carrier film 8 has a plurality of test notches 9 which are separated from one another by carrier film tabs 10. Here, in this embodiment, the carrier film 8 is also arranged such that the test notches 9 overlap with the pressure equalizing notches (not visible in this view) and the carrier film tabs also at least partially cover the test notches.

[0029] In other words, in the mass production of housings with pressure equalizing elements, a roll of such pressure equalizing elements has hitherto been provided, wherein on the roll a plurality of pressure equalizing elements are wound on a carrier film, similar to a roll on which labels are wound on a carrier film. Such a roll with pressure equalizing elements can be placed in an automatic dispenser which separates the pressure equalizing elements such that a robot gripper can pick up the pressure equalizing elements individually. A production robot with the said robot gripper then mounts the pressure equalizing elements on a housing having pressure equalizing notches.

[0030] Subsequently, the installed pressure equalizing element can be covered with a negative pressure hood or an overpressure hood using a second robotic gripper and in particular loaded with negative pressure to test the pressure equalizing element. By means of this negative pressure regulation, the test air flow through the installed pressure equalizing element is adjusted, and then the test air flow flowing through the pressure equalizing element in the installed state is measured. It has been shown that the pasting / compressing of the pressure equalizing element, i.e., the installation onto the interface, squeezes them together and this deformation can affect the flow-through over a long period of time. Therefore, the pressure equalizing element installed immediately after pasting can have different flow values compared to a pressure equalizing element that has been pasted for a long time, in particular for several hours. In the case of the pressure equalizing element installed immediately afterwards, the flow value is smaller than in the case of an uninstalled or already installed pressure equalizing element for a long time, because in the case of pressure equalization, the diaphragm being flowed through is to some extent "squeezed together" and relaxes again over time. If it is assumed that there is a correlation between the "squeezed" diaphragm and the desired normal value of the flow rate for said diaphragm, then a functional test can also be carried out in the "squeezed" state. However, the disadvantage of this method here is that instead of measuring the specific limit value for the flow-through, only the test air flow of the compressed diaphragm can be detected. For rework, when the pressure equalizing element is considered abnormal (abnormal state) when measuring the test air flow, then costly rework is required.

[0031] In contrast, it is proposed that the carrier film carrying the pressure equalizing element in a rolled-up manner is designed such that the carrier film has at least one notch, a so-called test notch, for each pressure equalizing element. Before removing the pressure equalizing element from the carrier film, the test notch enables, for each pressure equalizing element, which is necessary for installation, in order to carry out a functional test. For this purpose, the pressure hood can cover the pressure equalizing element from at least one side and be closed with the carrier film, and a test pressure (overpressure or negative pressure) in the pressure hood is applied to the pressure equalizing element and thus a pressure difference is generated, which causes a test air flow to pass through the pressure equalizing element. Here, the test air flow can flow through an opening in the carrier film. Since in this way, unlike in the case where the carrier film does not have a corresponding notch, the diaphragm of the pressure equalizing element is not compressed, a realistic functional test of the pressure equalizing element can be carried out.

[0032] In particular, with the proposed embodiment of the carrier film, a reduction in cycle time is achieved during the installation and functional testing of the pressure equalizing element. Before applying the pressure equalizing element, a defective pressure equalizing element can be identified before its installation. Therefore, the risk of rework and cycle time losses is reduced. The functional test of the non-compressed pressure equalizing element can also be carried out in this way. Modeling related to the "flow value immediately after pasting" can be dispensed with and thus fault identification can be further improved.

[0033] List of Reference Numerals

[0034] 1 Pressure balance element

[0035] 2 First thin film

[0036] 3 First surface of 2

[0037] 4 Second thin film

[0038] 5 Second surface of 2

[0039] 6 Diaphragm

[0040] 7 Pressure balance notch in 2

[0041] 8 Carrier film

[0042] 9 Test notch in 8

[0043] 10 Carrier film tab

[0044] 11 Test air flow

Claims

1. A pressure equalizing element for attachment to a surface of a housing or other object provided with a pressure equalizing opening, wherein, The pressure equalizing element has: - a first membrane (2) designed to have a first surface for pasting onto the surface of the housing, and - a second membrane (4) that is at least sectionally connected to the first membrane on a second surface (5) of the first membrane opposite the first surface (3), and - a diaphragm (6) that is geometrically arranged between the first membrane (2) and the second membrane (4) on the second surface (5) of the first membrane (2), wherein the first membrane (2) has a pressure equalizing notch (7) that is covered by the diaphragm (6), characterized in that the pressure equalizing element (1) is received on a carrier film (8) using the first surface (3) of the first membrane (2) before being mounted on the surface of the housing, and for the purpose of this mounting, the carrier film (8) can be removed from the first surface (3), and the carrier film (8) has at least one test notch (9), and the test notch (9) and the pressure equalizing notch (7) at least partially overlap.

2. The pressure balance element according to claim 1, characterized in that, The carrier film has a plurality of test notches (9) that are separated from each other by carrier film tabs, at least one or more of the test notches overlap at least partially or completely with the pressure equalizing notch, and at least one of the carrier film tabs at least partially covers the test notch.

3. The pressure balance element according to claim 1, characterized in that, The carrier film has at least one test notch, and the test notch and the pressure equalizing notch are arranged to coincide with each other.

4. A method for mounting a pressure equalizing element, the pressure equalizing element being the pressure equalizing element according to any one of the preceding claims, the method having the following steps: - receiving the pressure equalizing element with the carrier film in a test device, - applying a pressure difference between the side of the pressure equalizing element on which the carrier film is arranged and the side of the pressure equalizing element opposite this side, such that a test air flow through the pressure equalizing element occurs due to the pressure difference, - evaluating the pressure equalizing element based on the test air flow, - removing the carrier film from the first surface of the first membrane, - mounting the pressure equalizing element on the surface of the housing.

5. The method for installing a pressure balancing element according to claim 4, characterized in that, For evaluating the pressure equalizing element, the test air flow is detected indirectly or directly, and the detected test air flow is compared and evaluated with a rated test air flow.

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