Heated cleaning device

Abstract

The invention relates to a cleaning device (1) for a cleaning apparatus (2) arranged in a vehicle, comprising a housing (3) having a chamber (4) formed in the housing (3), which can be filled with cleaning fluid and can be hydraulically connected to at least one spray nozzle (5) for the cleaning fluid, and having at least one heatable heating wire (6) which at least partially projects into the chamber (4). The object of the invention is to achieve a high level of functional reliability even at low temperatures and to be able to de-ice particularly quickly and reliably. According to the invention, this object is achieved in that a heat-conducting element (7) is arranged in the chamber (4) to enlarge the heat transfer convection surface, which heat-conducting element absorbs heat from the heating wire (6), the cleaning fluid flowing at least around some regions of the heat-conducting element, in particular around the entire heat-conducting element.

Description

Technical Field

[0001] This invention relates to a cleaning apparatus for use in a vehicle cleaning system. Background Technology

[0002] Cleaning devices are known for use in vehicle cleaning systems, used to clean windows, headlights, cameras, etc., with a cleaning fluid. To effectively clean multiple cleaning points that are relatively far apart and / or large areas, multiple such cleaning devices are often connected in series within the cleaning system to a common fluid line, forming a so-called nozzle chain. Freezing can occur at temperatures below the freezing point of the cleaning fluid, potentially clogging the cleaning devices or even damaging them due to expansion. To avoid this, it is known to design the cleaning devices as heated, particularly by guiding one or more heating wires through the device to heat the cleaning fluid. Reliable and rapid de-icing to restore flowability is a major challenge here.

[0003] WO 0056584 A1 discloses a nozzle chain having multiple cleaning devices connected in series via fluid lines. A separate heating line runs through the fluid lines and cleaning devices to heat the nozzle chain. This separate heating line extends through a fluid channel within the housing of the cleaning device, which is used to deliver cleaning fluid through the nozzle chain. The fluid channel is connected within the housing of the cleaning device to a chamber via one or more connecting channels, the chamber leading directly to a simple nozzle opening or to a spherical insert with a nozzle opening. However, with this design, effective de-icing of the nozzle opening, which is relatively far from the heating wire, cannot always be reliably performed because the heat released by the heating wire inside the housing is too low.

[0004] DE 102008003881 A1 discloses a cleaning device that is improved in this respect and has an enlarged cuboid-shaped fluid chamber arranged in a housing and closed by a welded cap. Fluid channels, in their respective cases, lead to opposite walls of the fluid chamber. A fluid inlet is located at the center of the bottom of the fluid chamber, surrounded by a protruding shoulder and leading to a jet insert. Furthermore, two retaining connecting plates are arranged on the bottom of the fluid chamber. A heating wire, guided through the fluid channels, is guided in a meandering manner around the retaining connecting plates and the shoulder within the fluid chamber, which allows for better heating of the nozzle unit.

[0005] The assembly process for heating wires laid out in this manner during manufacturing has proven to be extremely complex. Furthermore, there is a risk that assembly tools or protruding parts may damage the insulation of the heating wires.

[0006] In addition, there is a risk that the housing of this cleaning device may bulge open due to ice buildup within it. Summary of the Invention

[0007] Therefore, the object of the present invention is to provide an improved heated cleaning device that can be used in nozzle chains and is easier to manufacture, enabling high functional safety and rapid and reliable de-icing even at low temperatures.

[0008] This objective is ultimately achieved through the cleaning device described below.

[0009] Specifically, a cleaning device for a cleaning apparatus arranged in a vehicle includes a housing made of a thermoplastic material and having a cavity formed therein, the cavity being capable of being filled with a cleaning fluid and hydraulically connected to at least one spray nozzle for the cleaning fluid, wherein a connection channel for connecting the cavity to the spray nozzle extends into the cavity, and the housing has at least one heatable heating wire extending at least partially into the cavity, the heating wire being at least partially surrounded by the cleaning fluid, characterized in that a separate thermally conductive element is arranged in the cavity to expand the heat transfer surface, the thermally conductive element absorbing heat from the heating wire and being at least partially surrounded by the cleaning fluid, wherein the thermally conductive element is designed as an insert, made of a material with a thermal conductivity higher than that of the housing material, and is partially laid on or mechanically pressed against the heating wire for heat absorption purposes, wherein the thermally conductive element at least partially surrounds the connection channel in the circumferential direction relative to the longitudinal axis of the connection channel, and wherein the thermally conductive element is disc-shaped.

[0010] The present invention provides a heat-conducting element having an enlarged heat-dissipating surface for rapid and uniform heat distribution in a chamber. This heat-conducting element absorbs heat from a heating wire and is preferably completely surrounded by a cleaning liquid.

[0011] This allows for the linear laying of the heating wire in a manner that facilitates assembly and manufacturing, while still enabling rapid heating of the cleaning fluid over large areas. The risk of edge damage to the heating wire insulation from assembly tools or plastic parts is significantly reduced. The heating wire can be designed to be shorter because there is no need to lay loops.

[0012] According to an advantageous development of the invention, it is possible to distribute heat more effectively and quickly to functionally important parts of the cleaning device, because the connecting channel for connecting the chamber to the spray nozzle leads into the chamber, and the heat-conducting element surrounds the connecting channel at least partially, and especially entirely, in the circumferential direction relative to the longitudinal axis of the connecting channel.

[0013] The heat-conducting element, designed in a disc shape, can achieve a particularly high level of efficiency in terms of manufacturability, manipulation, and heat dissipation surface.

[0014] The cleaning device achieves a high level of safety because a membrane made of an elastomeric material is placed within the housing, which hydraulically seals the chamber relative to the ambient atmosphere. When the cleaning fluid freezes, the expansion of the ice is compensated for by the elastic deformation of the membrane, thus preventing damage to the housing. This also allows the housing to be designed with thin walls, which is particularly cost-effective.

[0015] For particularly simple production and assembly, the membrane can be clamped between the housing and the housing cover fastened to the housing in a hydraulically sealed manner.

[0016] The membrane's sealing function allows the housing cover to be fastened to the housing via a simple snap-lock connection instead of welding. By avoiding welding, machine costs, quality, and testing requirements can be significantly reduced.

[0017] The membrane's functionality is effectively maintained in all operating conditions by providing at least one ventilation opening for pressure balancing in the housing cover, which establishes a pneumatic connection between the ambient atmosphere and the membrane's side away from the chamber.

[0018] The efficiency of the cleaning device can be improved by increasing functional integration, because the inlet connecting the channel to the chamber has a sealing edge that can contact the membrane seal and thus form a shut-off valve for pressure control of the connection channel.

[0019] The particularly compact construction of the cleaning device and the efficient heat distribution are facilitated by the fact that the connecting channel to the spray nozzle is oriented substantially laterally relative to the longitudinal axis of the connector, which has an inlet channel extending therein for supplying the chamber.

[0020] If the housing is pivotally mounted within a fixedly attached outer housing of the vehicle, the injection direction can be flexibly and adaptively set. Pivot mounting can be particularly effective if the pivot axis is designed concentrically with respect to the longitudinal axis of the connector. Pivot mounting is also particularly effective if the connector itself forms the pivot axis and is clamped in a pivot seat within the outer housing for this purpose, thus eliminating the need for separate pins, etc.

[0021] If the chamber is designed to be substantially annular around the longitudinal axis of the connecting channel, it facilitates efficient heat distribution and further simplifies manufacturing and assemblability.

[0022] This achieves a particularly simple and efficient connection between the heat-conducting element and the heating system because the heat-conducting element is configured as an insert and is placed only partially on the heating wire or mechanically pressed against the heating wire, thus eliminating the need for fixed connections made by welding, fusion or crimping.

[0023] To achieve effective heat conduction and dissipation, the heat-conducting element can be made of a material with a higher thermal conductivity than the housing material, especially a metallic material, preferably a corrosion-resistant copper alloy or a plastic with a separate thermal conductive treatment.

[0024] Furthermore, the present invention claims protection for a cleaning device that incorporates a cleaning apparatus according to the present invention in its construction. Attached Figure Description

[0025] The invention will now be explained in more detail with reference to preferred exemplary embodiments. In the accompanying drawings:

[0026] Figure 1 A cleaning apparatus including a nozzle chain having multiple cleaning devices according to the invention connected in series is shown.

[0027] Figure 2 An exploded view of a preferred embodiment of the cleaning device is shown.

[0028] Figure 3 A cross-sectional view of the cleaning device is shown, transverse to the longitudinal axis of the connector.

[0029] Figure 4 A top view of the housing of the cleaning device is shown; the housing is not equipped except for the installed heating wire. Detailed Implementation

[0030] Figure 1

[0031] exist Figure 1 The image shows a simplified, rather than scaled, heated cleaning device 2, configured as a so-called nozzle chain, used for cleaning vehicle windows. Multiple cleaning units 1, 1', 1" are connected in series on a common fluid line 12. In the illustrated embodiment, each of the cleaning units 1, 1', 1" has: an outer housing 14 immovably connected to a vehicle component, such as an attachment to the hood; and a housing 3 pivotally mounted within the outer housing 14, from which a jet of cleaning fluid exits through a window provided in the outer housing 14.

[0032] The cleaning equipment is supplied with cleaning fluid under pressure via a hydraulic interface 15 from a delivery device (not shown here).

[0033] Heating lines supplied with current via electrical interface 16 are laid through fluid lines 12 and cleaning devices 1, 1', 1" . When the current is activated, the heating lines are heated along their entire length, thus heating the cleaning fluid around them. The heating lines are typically laid in long loops with both ends connected to the electrical interface, such that each cleaning device 1, 1', 1" is extended through by two separate heating wires.

[0034] According to the present invention, as long as at least one cleaning device 1 as described below exists, deviations in the overall structure and the quality of individual components of the cleaning equipment 2 are permissible at all times.

[0035] Figure 2

[0036] Figure 1 A preferred embodiment of the cleaning device 1 is shown in an exploded view. Two connectors 11, 11' for connecting the fluid line 12 are arranged aligned with each other on the housing 3. A chamber 4 is formed in the housing 3. This chamber is filled with cleaning fluid from an inlet channel 13 extending through the connector 11. Heating wires 6, 6' extend through the inlet channel 13 and the chamber 4. The cleaning fluid is supplied via a connecting channel 8 (see...). Figure 3 The cleaning fluid is guided from chamber 4 to spray nozzle 5, where it is sprayed from outlet openings 17, 17' onto the surface to be cleaned. In the illustrated embodiment, spray nozzle 5 is designed as a cubic insert element (also referred to as a "chip"), which is received in a receiving seat 18 with a rectangular cross-section within housing 3.

[0037] The housing 3 is typically made of a poorly thermally conductive thermoplastic material, such as polyamide. To increase heat dissipation to the cleaning fluid, a separate, well-conducting heat-conducting element 7 is used. The disc-shaped heat-conducting element 7 is placed in the chamber 4 in such a way that it is in mechanical contact with the heating wires 6, 6' in some areas and thus absorbs heat from the heating wires. In principle, all materials that are durable in the operating environment and have high thermal conductivity (especially metals) are suitable as materials for the heat-conducting element 7. However, plastics with improved thermal conductivity can also be used, for example, by using ceramics, metals, or other suitable fillers.

[0038] An elastic membrane 9 is inserted into the housing 3 relative to the environmental defining chamber 4. This elastic membrane is sealed and pressed tightly by the housing cover 10. The housing cover 10 is secured to the housing 3 by corresponding locking elements 19, 20. For this purpose, the housing cover 10 has a plurality of tongue-shaped locking elements 19, 19', 19" which are provided with locking hooks and engage with corresponding eyelet-shaped locking elements 20, 20', 20" on the outer edge of the housing 3, thereby forming an undercut.

[0039] To set the injection direction, housing 3 is pivotally mounted in outer housing 14, which is immovably secured to the vehicle by fastening element 24. For this purpose, connectors 11 and 11' in corresponding pivot seats 23 and 23' clamped into outer housing 14 act as pivot shafts.

[0040] The adjusting screw 25, which operates between housing 3 and outer housing 14, is used to precisely set and permanently maintain the set pivot position.

[0041] Figure 3

[0042] exist Figure 3 The above-mentioned cleaning device 1, after assembly, is shown in cross-section. The outer housing 14 is not shown.

[0043] The chamber 4 is arranged substantially annularly around the longitudinal axis V of the centrally located connecting channel 8 in the housing 3. A membrane 9, made of elastomeric material, is hydraulically sealed between the housing 3 and the housing cover 10 at a sealing gasket 27 formed radially outward. A cavity 28 is formed between the housing cover 10 and the membrane 9.

[0044] The ventilation opening 21 in the housing cover 10 establishes a pneumatic connection to the cavity 28, and thus a pneumatic connection between the side of the membrane 9 facing away from the chamber 4 and the ambient atmosphere for pressure equalization purposes. This ensures that the membrane 9 can expand and protrude into the cavity 28 without obstruction, for example, when the chamber 4 is filled with cleaning fluid under pressure or when the cleaning fluid freezes to form an ice plug.

[0045] The inlet channel 13 and the two heating wires 6, 6' laid therein extend through the radially outer region of the chamber 4. The connecting channel 8 is oriented laterally relative to the longitudinal axis A of the connector 11 or the inlet channel 13 and enters the chamber 4 radially and centrally.

[0046] A surrounding collar 26 encloses the inlet of the connecting channel 8, and the collar has a sealing edge 22 on its end side. In the unoperated initial state shown here, the diaphragm 9 is elastically pre-tensioned onto the sealing edge 22, resulting in the connection channel 8 being blocked and the hydraulic connection between the chamber 4 and the injection nozzle 5 being prevented. When the delivery device is activated and the chamber 4 is filled with cleaning fluid under pressure, the diaphragm 9 bulges and lifts away from the sealing edge 22. This opens the connection channel 8, allowing the cleaning fluid to flow to the injection nozzle 5 and be discharged from the outlet openings 17, 17'. Therefore, the diaphragm 9 acts as a valve body, and the sealing edge 22 acts as a valve seat for a pressure-controlled shut-off valve.

[0047] A disc-shaped heat-conducting element 7 is located in chamber 4, where it is surrounded by cleaning fluid. At its radial center, the disc-shaped heat-conducting element completely surrounds the inlet portion of the connecting channel 8. An edge portion extends into the inlet channel 13, where it rests on the heating wire 6. Thus, heat is conducted from the heating wire to the heat-conducting element 7 via a simple mechanical connection. Due to its excellent thermal conductivity, the heat-conducting element 7 heats up rapidly overall and releases heat through its surface into the surrounding cleaning fluid for further convective heat transfer. As a result, heat from the heating wires 6, 6' is rapidly, extensively, and uniformly distributed throughout chamber 4. Simultaneously, the connecting channel 8 and the shut-off valve are also heated.

[0048] For better heat conduction, the heat-conducting element 7 can also be mechanically squeezed or pressed against the heating wires 6, 6', for example, by clamping it radially on the outside or inside of the housing 3.

[0049] Figure 4

[0050] To illustrate the preferred design of the housing of cleaning device 1, Figure 4 The housing 3 is shown in top view.

[0051] In its preferred embodiment, the chamber 4 is designed in a flow-facilitating manner to annularly surround the radially centered inlet of the connecting channel 8. The two connectors 11, 11' are positioned in the radially outer region of the housing 3, and the inlet channel 13 and the heating wires 6, 6' laid linearly directly in the inlet channel for ease of assembly extend only through the radially outer region of the chamber 3.

[0052] List of reference numerals

[0053] 1. Cleaning device

[0054] 2. Cleaning equipment

[0055] 3. Shell

[0056] 4 chambers

[0057] 5. Injection nozzle

[0058] 6 Heating wire

[0059] 7. Thermal conductive elements

[0060] 8 Connection Channels

[0061] 9. Membrane

[0062] 10. Housing cover

[0063] 11 Connectors

[0064] 12 Fluid Piping

[0065] 13 Entrance passage

[0066] 14. Outer casing

[0067] 15 Hydraulic Interface

[0068] 16 Electrical Interfaces

[0069] 17. Exit opening

[0070] 18 Reception Seats

[0071] 19. Locking components

[0072] 20 Locking Components

[0073] 21 Ventilation openings

[0074] 22 Sealing edge

[0075] 23 Pivot

[0076] 24 Fastening components

[0077] 25 Adjusting screws

[0078] 26-inch collar

[0079] 27 Sealing gasket

[0080] 28. Cavity

[0081] A. The longitudinal axis of the connector

[0082] V is the vertical axis of the connecting channel.

Claims

1. Cleaning device (1) for a cleaning apparatus (2) arranged in a vehicle, comprising a housing (3) made of thermoplastic material and having a chamber (4) formed in the housing (3), which chamber can be filled with a cleaning liquid and can be hydraulically connected to at least one jet nozzle (5) for the cleaning liquid, wherein a connecting channel (8) for connecting the chamber (4) to the jet nozzle (5) opens into the chamber (4), and the housing has at least one heatable heating wire (6) which at least partially projects into the chamber (4) and which is at least partially surrounded by the cleaning liquid, characterized in that A separate heat-conducting element (7) is arranged in the chamber (4) to enlarge the heat transfer surface, which heat-conducting element absorbs heat from the heating wire (6) and is at least partially surrounded by the cleaning liquid, wherein the heat-conducting element (7) is designed as an insert, consists of a material whose heat conductivity is higher than that of the housing (3), and is partially laid on the heating wire (6) or mechanically pressed against the heating wire for heat absorption purposes, wherein the heat-conducting element (7) at least partially surrounds the connection channel (8) in the circumferential direction with respect to the longitudinal axis (V) of the connection channel (8), and wherein the heat-conducting element (7) is disc-shaped.

2. A cleaning device (1) according to claim 1, characterized in that A membrane (9) made of an elastomer material is arranged in the housing (3), which membrane delimits the chamber (4) and hydraulically seals the chamber against the ambient atmosphere.

3. A cleaning device (1) according to claim 2, characterized in that The membrane (9) is clamped in a hydraulically sealing manner between the housing (3) and a housing cover (10) fastened to the housing (3).

4. A cleaning device (1) according to claim 3, characterized in that The housing cover (10) is fastened to the housing (3) via a latching connection.

5. A cleaning device (1) according to claim 3, characterized in that The housing cover (10) has at least one ventilation opening (21) for pressure equalization between the side of the membrane (9) facing away from the chamber (4) and the ambient atmosphere.

6. A cleaning device (1) according to claim 2, characterized in that The entry of the connection channel (8) into the chamber (4) has a sealing edge (22) which can be sealingly abutted against the membrane (9) and thus forms a pressure-controlled shut-off valve for shutting off the connection channel (8).

7. A cleaning device (1) according to claim 1, characterized in that The housing (3) has at least one connection piece (11) for connecting a fluid line (12), and the chamber (4) is filled with cleaning liquid from an inlet channel (13) extending through the connection piece (11), and the connection channel (8) is oriented substantially transversely with respect to the longitudinal axis (A) of the connection piece (11).

8. A cleaning device (1) according to claim 7, characterized in that The housing (3) is pivotably mounted in an outer housing (14) for setting the spray direction, wherein the pivot axis is designed concentrically with respect to the longitudinal axis (A) of the connection piece (11).

9. A cleaning device (1) according to claim 8, characterized in that The connection piece (11) forms the pivot axis.

10. A cleaning device (1) according to claim 1, characterized in that The chamber (4) is designed to substantially encircle the longitudinal axis (V) of the connection channel (8) in an annular manner.

11. A cleaning device (1) according to claim 1, characterized in that The heating wire (6) is laid substantially straight through the edge region of the chamber (4).

12. A cleaning device (1) according to claim 1, characterized in that The heat-conducting element (7) consists of a metallic material.

13. A cleaning device (2) comprising at least one cleaning apparatus (1) according to any one of the preceding claims.

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