Patent Application
20210060585
The present invention relates to automated or remotely controlled methods and apparatus for cleaning soiled objective lenses on video cameras or image sensors when mounted in a location or configuration in which the lenses are exposed to an environment which may cause an accumulation of dirt on the lens.
An increasingly wide range of cars, trucks, SUVs, recreational vehicles and the like incorporate as original equipment integrated video cameras or other sensors which generate an image for display to the driver, operator or other occupants or users within the vehicle's interior. Such cameras or sensors typically provide a view of the exterior surroundings of the vehicle and may be mounted on any surface of the vehicle, often on the front grille or bumper to provide a forward view, on the side panels or mirrors to provide a side view, or on the trunk, rear window or bumper to provide rearward or back-up views to enhance the drivers vision and to improve safety. These cameras or sensors allow drivers to see whether obstacles surround their vehicle using a display screen mounted either on a rear-view mirror or in a navigation system screen.
The external image sensors such as those known as back-up or rear view cameras are typically mounted unobtrusively, and typically are incorporated into existing features such as the vehicle's rear name plate. These external cameras are exposed to the vehicle's harsh environmental surroundings and are often soiled by mud, salt spray or dirt which accumulates on the lens. Accumulating dirt and debris often distort the image that the drivers are viewing, thus creating confusion, dissatisfaction or a safety issue due to poor judgment by relying on an unclear picture.
The advent of low cost, reliable imaging devices using solid-state sensor technologies (e.g., CMOS pixel sensor technology), combined with an improved cost/performance ratio for video displays capable of meeting automotive specifications, and an increasing application rate of video monitor displays for automotive navigation systems and the like, has led to an increasing use of cameras or imaging sensors designed to give the driver a view of those areas around the vehicle which are not in the normal direct field of view of the driver, typically referred to as “blind spots”. These areas include the region close to the front of the vehicle, typically obscured by the forward structure of the vehicle, the region along the passenger side of the vehicle, the region along the driver's side of the vehicle rearward of the driver, and the area or region immediately rearward of the vehicle which cannot be seen directly or indirectly through the rear-view mirror system. A camera or imaging sensor may capture an image of the rearward (or sideward or other blind spot area) field of view, and the image may be displayed to the driver of the vehicle to assist the driver in backing up or reversing or otherwise driving or maneuvering the vehicle.
Since the use of electronic cameras in vehicle imaging systems can significantly increase a diligent driver's knowledge of the space immediately surrounding the vehicle prior to and during low speed maneuvers, contributing to the safe completion of such maneuvers, it has become common to provide one or more cameras or imaging sensors on a vehicle to provide images of exterior blind spot scenes for the driver. Furthermore, cameras or sensing devices are becoming widely available for detecting the location of the vehicle with respect to lane markings, spacing from other vehicles and the like to provide additional driver assistance for controlling speed, distance and location.
Such cameras or sensors are mounted in a variety of locations on a vehicle, where they may be vulnerable to damage by the harsh conditions that may be encountered even under normal driving conditions. In particular, for camera sensors mounted on the exterior of a vehicle, protection against environmental effects such as rain, snow, road splash and/or the like, is important. Accordingly, it is often desirable to position them within a protective housing such as, for example, a metallic protective housing such as a die cast housing of aluminum or zinc or the like which may be closed about the camera or sensor and secured together via fasteners or screws or the like. In known exterior camera sensor mounts, a butyl seal, such as a hot dispensed butyl seal, or an 0-ring or other sealing member or material or the like, has been provided between the parts of the housing to assist in sealing the housing to prevent water or other contaminants from entering the housing and damaging the camera or sensor positioned therein. However, such housings typically do not provide a substantially water tight seal, and water droplets thus may enter the housing. Furthermore, any excessive vibration of the camera sensor, due to its placement (such as at the exterior of the vehicle), may lead to an undesirable instability of the image displayed to the driver of the vehicle. Since such cameras or sensors are costly to manufacture and to implement on vehicles, it is important to protect them against such damage.
The cameras for rearward vision systems are typically placed or mounted in a location that tends to get a high dirt or moisture buildup on the camera and/or lens of the camera, with no easy way of cleaning the camera and/or lens. In order to reduce such buildup on the cameras, prior art developers proposed using hydrophilic or hydrophobic coatings on the lenses. However, the use of such a coating is not typically effective due to the lack of air flow across the lens, especially within a sealed housing. Also, the appearance of such cameras on the rearward portion of vehicles is often a problem for styling of the vehicle. The prior art U.S. Pat. No. 7,965,336 to Bingle, et al. discloses a camera module with a plastic housing for the image sensor, and which is operable to capture images of a scene occurring exteriorly of the vehicle. Bingle's camera housing assembly is welded together with the image sensor and associated components within enclosed the plastic housing, and includes a “breathable” ventilation portion that is at least partially permeable to water vapor to allow emission of internal water vapor. This design substantially precludes passage of water droplets and other contaminants into the housing and seeks to minimize problems arising from fluid impacting or accumulating within the housing.
The Bingle patent also discloses the use of a coating to keep the objective lenses' view clear, and its housing or cover is optionally provided with an anti-wetting property such as the hydrophobic coating (or stack of coatings) as disclosed in U.S. Pat. No. 5,724,187. Bingle notes that a hydrophobic property on the outermost surface of the cover can be achieved by a variety of means, such as by use of organic and inorganic coatings or by utilizing diamond-like carbon coatings. But Bingle and others do not propose actually taking any affirmative action to remove road debris (e.g., accumulated dirt, dust, mud, road salt or other built-up debris) apart from using such coatings or surface treatments.
Based on consumer preference and at least a perceived improved ability to extract information from the image, it is desired to present an image to the driver that is closely representative of the exterior scene as perceived by normal human vision. It is also desirable that a vehicle's imaging devices or systems be useful in all conditions, and particularly in all weather and lighting conditions. However, it is often difficult to provide an imaging sensor which is capable of providing a clear image in poor weather, especially while driving. This is because conventional imaging systems typically have difficulty resolving scene information when the camera's objective lens is partially obstructed by accumulated debris (e.g., accumulated dirt, dust, mud, road salt or other built-up debris).
In order to have effective use of the camera-based visibility systems in all weather conditions, it is desirable to have an effective method of keeping the camera lens (or the housing surface protecting the objective lens) clean, but the potentially deleterious effects of moisture noted in the above-described Bingle patent remain.
When operating a vehicle during bad weather, drivers are especially reluctant to exit the vehicle to find and inspect the camera's lens. This reluctance likely explains why the inventors of U.S. Pat. No. 6,834,904 (to Vaitus et al) included a “Nozzle” that is “in close proximity to” a lens for the vehicle's camera or vision unit. The Vaitus '904 patent generally discloses a structure and method for mounting a “Vehicle Liftgate with Component Module Applique” wherein an applique module is adapted for attachment to a vehicle liftgate and, as shown in this patent, the module includes a nozzle which receives fluid from a conduit. However, as noted in the patent, “cleaning of lens 84 may be implemented in other ways” such as hydrophobic lens coatings. It appears that the module and nozzle arrangement described so indifferently in the Vaitus 904 patent was not deemed to be a practicable or effective solution meriting further development, and so appears to have been ignored.
However, the instant applicants have been working in this area and have published patent applications, including Published US Application 20160001330, entitled “Integrated automotive system, nozzle assembly and remote control method” which describe and illustrate prior work for cleaning an image sensor's exterior or objective lens surface by the use of a fluid nozzle directing fluid onto the lens surface. As noted in the '330 application, conserving cleaning fluid is a priority for Automotive OEMs, and so the need to adequately clean a lens surface must be balanced with the need to avoid use of too much water. There is a need, therefore, for a convenient, effective and unobtrusive system and method for cleaning an exterior objective lens surface, preferably by remote control, wherein the system satisfactorily cleans the lens without overusing the limited supply of fluid typically provided in an automobile.
All passenger automotive vehicles contain washer systems to clean the front windscreen and provide a clear field of vision to the driver. These same vehicles may contain additional nozzles to clean the rear window or the headlamps, or, as discussed above, to clean image sensors such as cameras or LIDAR. Typically, a single pump drives the washer system and is designed and sized to supply fluid for the highest flowrate portion of the system, either the front windscreen nozzles or the headlamp nozzles. But an automotive washer system often has multiple branches. A multi-branch system may be supplied with a dual outlet pump or with two or more similar single or dual outlet pumps. Consequently, when fluid is demanded at a location such as a sensor or at the rear window where a lower target flowrate is desired to conserve fluid, the pump is oversized for the application and generates more pressure than may be necessary for cleaning. This higher pressure results in a high flow rate and excessive fluid consumption. Conservation of fluid is desirable on all vehicles, but becomes critical when a vehicle contains multiple nozzles, such as when one or more sensors or objectives are washed.
Typically the flow rate is constrained by restricting the size of the fluid outlet. This is undesirable, however, as the likelihood of clogging the nozzle increases in inverse proportion to the size of the nozzle outlet. Additionally, difficulty of manufacturing also increases in inverse proportion to the size of the nozzle outlet, and normal manufacturing tolerances have an increased effect on the performance of smaller nozzles than would be observed on proportionally larger nozzles.
Accordingly, it is an object of the present invention to overcome the above-mentioned difficulties by providing a lens cleaning system for automotive applications wherein a fluid spray is supplied from a pressurized fluid source to a nozzle at flow rates that are sufficient to adequately clean a lens without wasting fluid.
It is a further object of the invention to provide a lens cleaning system for multiple lenses in an automotive application, wherein fluid is supplied from a single pressurized fluid supply to multiple spray nozzles with minimal flow variation.
It is another object of the invention to provide a lens cleaning system for multiple lenses in an automotive application incorporating fluid pressure compensation for reliably generating reduced flow rates while maintaining adequate lens cleaning.
It is another object of the invention to provide a lens cleaning system for multiple lenses in an automotive application which includes a pressure control device or flow regulator to provide a consistent flow rate despite fluctuations in system pressure.
It is still another object of the invention to provide a method for maintaining adequate cleaning fluid flow in a lens cleaning system for automotive applications wherein fluid is supplied from a pressurized fluid source to a nozzle at flow rates that are sufficient to adequately clean a lens without wasting fluid.
The system of the present invention overcomes the foregoing issues and problems by including a pressure control device or flow regulator in the washer system. Although pressure control devices exist and have been used in other fields, such as residential plumbing fixtures or irrigation devices where a constant flow rate is desired despite fluctuations in system pressure, the pressure flow system described herein is characterized by a flow rate versus pressure curve where for any pressure P, the flow rate Q1 is less than or equal to the flow rate of a fixed diameter orifice characterized by the equation Q=kP°5, where Q is flow rate, P is pressure, and k is a coefficient which varies with the orifice area.
As is known in the art, automotive washer systems typically incorporate a pump, tubing, one or more spray nozzles, and one or more check valves. The check valve(s) are generally located in close proximity to the nozzle(s) in order to keep the system primed between sprays. Some systems may additionally include one or more filters in order to screen particulate material from the fluid and thus prevent clogging of the nozzle, prolonging system life. The system may also include one or more connectors to join separate lengths of tubing. Briefly, in accordance with the present invention, an automotive washer system also incorporates a pressure control device which could be included as a separate component anywhere in the system to regulate flow to spray nozzles for cleaning camera lenses or other sensors, but which does not restrict flow to the primary wash area, either the front windscreen nozzles or the headlamp nozzles. Alternately, the pressure control device could be integrated into any of the components mentioned above: the nozzle, the check valve, the filter, or a connector. Commonly check valves are integrated into nozzles as a single subassembly. Two or more of these component types could be incorporated into a single device, such as a nozzle integrally containing both a pressure control device (PCD) and a check valve, or a filter integrally containing a PCD and a check valve.
The automotive wash system of the invention generally contains a fluidic, shear, or jet nozzle for washing sensors or lens components for automotive devices as well as glazing, mirrors and headlamps, and incorporates a source of fluid (42, 44) capable of providing a supply fluid flow rate of between 1 and 2500 mL/min with a supply pressure of between 1 and 80 psi and a pressure control device (180) fluidly connected between the source of fluid and a nozzle (50) in such a way that flow to the nozzle does not exceed 90% of the nominal flow rate without the pressure control device for supply pressures between 30 and 60 psi, or with a lower target flowrate for the same pressure range.
The pressure control, or compensating, device may be a flexible orifice type, an 0-ring type, a spring and piston device, a fluidic (e.g., vortex), or some other suitable in-line device. In accordance with a preferred aspect of the invention, the pressure control device comprises a flexible orifice combined with an in-line filter located in spray system tubing to reliably generate an optimum flow rate with changes in fluid pressure. In this preferred form, the spray nozzle is preferably a fluidic spray nozzle in which the supplied fluid under pressure produces a vortex to generate a desired spray output that may be directed at a lens or sensor surface to be cleaned. The pressure control device reliably produces flow rates which will maintain the nozzle vortex, but will prevent excessive flow even with a high pressure fluid supply so that the desired spray is produced without wasting fluid and without under-supplying the cleaning solution to the target lens or sensor surface and failing to provide the desired cleaning.
Broadly speaking, then, an automotive wash system in accordance with the present invention contains a fluidic, shear, or jet nozzle for washing sensors or lens components for optical devices as well as nozzles for washing glazing, mirrors and headlamps. The system operates with a supply fluid flow rate of between 1 and 2500 mL/min with a supply pressure of between 1 and 80 psi with the fluid supply being fluidly connected through a pressure control device (PCD), or flow regulator, in such a way that flow to the nozzle does not exceed 90% of the nominal flow rate without the PCD for supply pressures between 30 and 60 psi, or with a lower target flowrate for the same pressure range. The PCD is an elastomeric body incorporating multiple flexible tabs in the fluid flow path responsive to flow rate and pressure to vary the area of the flow path. More particularly, the pressure control device incorporates a toroidal body portion (290) formed by an annular wall (292) open at its top (301) and its bottom (304) and having annular upper (302) and bottom (306) flat surfaces, substantially cylindrical upper (294) and lower (295) inner surfaces, and a convex outer wall surface (296) surrounding and coaxial with an axis (298) to form a central through passageway (300). The device includes at least three inwardly-extending, flexible tabs (310, 312 and 314) extending inwardly from the wall (292) between the upper and lower inner wall surfaces (294, 295) and into the through passageway, with the tabs being spaced apart around the circumference of the inner wall 294 to form spaced, radially-extending slots (322, 324, 326) and a central opening (328). When at rest, the tabs provide a maximum fluid flow area through the slots and central opening; however, the tabs respond to fluid flow through the passageway to reduce the fluid flow area to limit the flow rate of the fluid.
In greater detail, the automotive washing system of the invention incorporates one or more “jumper hoses” which are in fluid communication with a conventional fluid source in which a pump supplies fluid from a reservoir at high flow rates and pressures sufficient to operate conventional windshield washers and the like. The jumper hose supplies this pressurized fluid to selected nozzles which clean such devices as cameras or camera lenses, and various other sensors, and may be referred to herein as “low-flow” or vortex-generating nozzles. The jumper hose of the invention incorporates a suitable connector at its input end for receiving fluid from the pump, at least a check valve, a filter and a pressure control device (PCD), a connector at its output end for connection to a nozzle, and suitable lengths of hose or tubing for interconnecting these components and for configuring the jumper hose to fit its particular automotive application. As herein described, the filter and the pressure control device preferably are combined in a single filter element housing.
In a preferred form of the invention, the PCD consists of a toroidal body portion 290 formed by an annular wall 292 having a substantially cylindrical upper inner surface 294, a substantially cylindrical lower inner surface 295, and a convex outer wall surface 296 surrounding and coaxial with an axis 298 to form a central through passageway 300. The body portion is open at its top 301, and has an annular upper flat rim, or surface 302. The bottom of the toroid 290 is also open, and has an annular flat bottom surface 306. Midway along the axial length of body portion 290 are preferably three inwardly-extending, flexible flaps, or tabs 310, 312 and 314 which extend inwardly from wall 292 between the upper and lower inner wall surfaces 294 and 295. The tabs are generally triangular in shape, and have arcuate bases 316, 318 and 320, respectively, where they meet the cylindrical side walls. The tabs are spaced apart around the circumference of the inner wall 294 with the edges of adjacent tabs being spaced apart to form three radially-extending slots 322, 324 and 326 extending outwardly from a central, or axial opening 328 toward the inner surfaces of wall 292. The tabs preferably are tapered inwardly in cross-section from their respective arcuate bases to respective central tips 330, 332 and 334 that are spaced around and define the central opening 328. The tabs intersect the upper wall surface portion 294 at an acute angle at an upper intersection 336, to form an upwardly-sloped rest position, and intersect the lower wall surface 295 at an obtuse angle at lower intersection 338.
The pressure control device 180 is constructed of an elastomeric material so that the tabs 310, 312 and 314 are flexible. The slots are sufficiently wide to ensure flexibility of the tabs and combine with the central aperture, or opening, to provide a maximum passage area for fluid passing through the device. The tabs respond to a predetermined fluid flow to flex downwardly and inwardly to gradually close the slots and to reduce the diameter of the central opening so that at a predetermined flow and pressure the tabs close the fluid passage area to a predetermined minimum, thereby limiting the flow rate through the PCD to a preset maximum, even with increased pressure. The selection of the characteristics of the material used to form the PCD, the dimensions of the tabs 310, 312 and 314 and thus the dimensions of the slots between the tabs, and/or the thickness of the flexible tabs determines the selected pressure/flow point at which the tabs reach a position in which flow is constricted to a desired flow rate through the area of the central aperture.
In summary, then, the automotive wash system of the invention contains a fluidic, shear, or jet nozzle for washing sensors or lens components for automotive sensor or camera devices as well as for washing glazing, mirrors, headlamps and the like, wherein the system includes a source of fluid (42, 44) capable of providing a supply fluid flow rate of between 1 and 2500 mL/min with a supply pressure of between 1 and 80 psi. The system incorporates at least one spray nozzle (50), with a pressure control device (180) fluidly connected between the source of fluid and the nozzle in such a way that flow to the nozzle does not exceed 90% of the nominal flow rate without the pressure control device for supply pressures between 30 and 60 psi, or with a lower target flowrate for the same pressure range. The pressure control device is an elastomeric toroidal body (290) incorporating multiple flexible tabs (310, 312, 314) extending into a fluid flow path (300) through the body and responsive to flow rate and pressure to vary the area of the flow path.
In a preferred form, the invention incorporates a combination filter and pressure control device (140) having a housing (142) with an inlet passageway (204) at an upstream end and an outlet passageway (212) at a downstream end (184) and a filter cartridge (176) in the filter housing, the cartridge having an extension (178) which engages the housing to position the filter cartridge in the housing and which receives the pressure control device. The flexible tabs in the pressure control device are spaced apart around the inner circumference of the PCD toroidal body to form spaced, radially-extending slots (322, 324, 326) and a central opening (328), with the tabs at rest forming a maximum fluid flow area through the slots and central opening. The tabs are responsive to fluid flow (339) through the passageway to reduce the fluid flow area to limit the fluid flow rate.
The combination filter and pressure control device further includes an annular rigid spacer (190) located in the filter cartridge extension, engaging a lower surface (360) of the pressure control device, and held by an end wall (186) of the outer housing in axial alignment within the housing to provide a flow path through the combination filter and pressure control device that is controlled by the flexible tabs. The rigid spacer sized to engage the lower surfaces of the tabs to regulate the flexing of the tabs in response to fluid flow.
The invention is further directed to a method for controlling fluid flow in an automotive wash system, the method including supplying a toroidal body portion (290) formed by an annular wall (292) open at its top (301) and its bottom (304) and having annular upper (302) and bottom (306) flat surfaces, substantially cylindrical upper (294) and lower (295) inner surfaces, and a convex or bulging outer wall surface (296) surrounding and coaxial with an axis (298) to form a central through passageway (300). The method further includes forming in the body portion at least three flexible tabs (310, 312 and 314) extending inwardly from the wall (292) between the upper and lower inner wall surfaces (294, 295) and into the through passageway and spacing the tabs around the circumference of the inner wall (294) to form spaced, radially-extending slots (322, 324, 326) and a central opening (328). The tabs at rest form a maximum fluid flow area through the slots and central opening and are responsive to fluid flow (339) through the passageway to reduce the fluid flow area to limit the flow rate of the fluid. The method also includes selecting the characteristics of the material used to form the flexible tabs, selecting the dimensions of the tabs and thus the dimensions of the slots between the tabs, and selecting the thickness of the flexible tabs to determine a selected pressure/flow point at which the tabs reach a closed position in which flow is constricted to the area of the central aperture.
The above and still further objects, features and advantages of the present invention will become apparent upon consideration of the following detailed description of a specific embodiment thereof, particularly when taken in conjunction with the accompanying drawings, wherein like reference numerals in the various figures are utilized to designate like components, and wherein:
In order to provide an exemplary context and basic nomenclature for the present invention, reference is made to
Referring now to
Camera housing 11 includes a camera housing portion 12 and a connector portion 14, which mate or join together and are preferably laser welded or sonic welded together to substantially seal the housing 11 to substantially limit or prevent water intrusion or other contaminants from entering the housing, as discussed below. Housing 11 substantially encases a camera or image sensor or sensing device 18 (
A camera or imaging sensor 18 useful with the present invention may comprise an imaging array sensor, such as a CMOS sensor or a CCD sensor or the like, such as disclosed in U.S. Pat. Nos. 5,550,677; 5,670,935; 5,796,094; 6,097,023, and 7,339,149. The camera module 10 and imaging sensor 18 may be implemented and operated in connection with various vehicular vision systems such as a forwardly, sidewardly or rearwardly directed vehicle vision system utilizing principles disclosed in U.S. Pat. Nos. 5,550,677; 5,670,935; 5,760,962; 5,877,897; 5,949,331; 6,222,447; 6,302,545; 6,396,397; 6,498,620; 6,523,964; 6,611,202; and 6,201,642, a trailer hitching aid or tow check system, such as the type disclosed in U.S. Pat. No. 7,005,974, a reverse or sideward imaging system, such as for a lane change assistance system or lane departure warning system, such as the type disclosed in U.S. Pat. No. 7,038,577, a system for determining a distance to a leading or trailing vehicle or object, such as a system utilizing the principles disclosed in U.S. Pat. No. 6,396,397, or the like.
For example, the camera or sensor 18 may comprise a LM9618 Monochrome CMOS Image Sensor or a LM9628 Color CMOS Image Sensor, both of which are commercially available from National Semiconductor. Other suitable cameras or sensors from other vendors (e.g., Sony®, Panasonic®, Magna™ and others) may be implemented with the camera module.
Although shown at a rear portion 8a of vehicle 8, image sensor 18 and camera module 10 may be positioned at any suitable location on vehicle 8, such as within a rear panel or portion of the vehicle, a side panel or portion of the vehicle, a license plate mounting area of the vehicle, an exterior mirror assembly of the vehicle, an interior rearview mirror assembly of the vehicle or any other location where the camera may be positioned and oriented to provide the desired view of the scene occurring exteriorly or interiorly of the vehicle. The camera module 10 is particularly suited for use as an exterior camera module. The image captured by the camera may be displayed at a display screen or the like that is positioned at a selected location within the cabin of the vehicle, such as at an interior rearview mirror assembly (such as disclosed in U.S. Pat. No. 6,690,268), or elsewhere at or within the vehicle cabin, as by using the principles disclosed in U.S. Pat. Nos. 5,550,677; 5,670,935; 5,796,094; 6,097,023 and 6,201,642, and/or 6,717,610.
As best shown in
Lens system 24 is positioned within cylindrical portion 12a of camera portion 12 to receive light from the exterior or interior scene through cover 22 at end 12c of camera portion 12. Lens system 24 is mounted, as by threaded engagement, to camera cover or housing 28, which functions to substantially cover or encase camera or sensor 18 to substantially prevent or limit incident light from being received by camera sensor 18 and interfering with the image received through cover 22 and lens system 24. The lens system 24 may be any small lens or lens system which will focus an image of a scene exterior of the camera module onto the camera image sensor 18, such as, for example, the types disclosed in U.S. Pat. No. 6,201,642 or 6,757,109. The lens system 24 may provide a wide-angle field of view, such as approximately 120 degrees or more (as illustrated in
Cover portion 20 is mounted at an outer end 12c of camera housing portion 12 opposite from base portion 12b, as shown in
In the illustrated embodiment, base portion 12b is generally square and defines a generally square mating edge 12e around the base portion for mating and securing it to a corresponding edge 14g of connector portion 14 at joint 13. Base portion 12b receives circuit board a 26 and image sensor 18 therein, while a camera housing or shield 28 and lens or lens system 24 extend into cylindrical portion 12a of camera portion 12 to receive an image through transparent cover 22.
Connector portion 14 of housing 11 is a molded plastic component and includes a connector terminal or connector 14a, such as a multi-pin snap-on connector or the like, extending from a base portion 14b. Base portion 14b is formed (such as in a square shape as shown in the illustrated embodiment) to substantially and uniformly mate or connect to base portion 12b of camera housing 12, as can be seen with reference to
Multi-pin connector 14a extends from base portion 14b and includes a plurality of pins or terminals 14c for electrically connecting camera module 10 with a connector (not shown) on a wiring harness or cables of the vehicle. For example, ends 14d of terminals 14c may connect to circuit board 26, while the other ends 14e of terminals 14c connect to the corresponding connector of the vehicle. The corresponding connector may partially receive the ends 14e of pins or terminals 14c at multi-pin connector 14a and may snap together with multi-pin connector 14a via a snap connection or the like. As best shown in
As shown in
As described above, the camera module 10 may be substantially hermetically sealed, so that water intrusion into the module is limited or substantially precluded. Base portion 12b of camera housing portion 12 and base portion 14b of connector portion 14 are correspondingly formed so as to substantially mate or join together at their mating seam 13, whereby the portions may be laser welded or sonic welded together or otherwise joined, while cover portion 20 is also laser welded or sonic welded or otherwise secured and substantially sealed at the opposite end 12c of camera portion 12, in order to substantially seal the camera housing. Laser or sonic welding techniques are preferred so as to join the materials at a state where they are able to re-flow, either via heat, vibration or other means, such that the materials re-flow and cross-link and become a unitary part. Such joining results in a substantially hermetically sealed camera module. Additionally, the pores in the plastic as well as any voids around the insert molded pins and stampings may be sealed with a Loctite® brand sealing material or other suitable sealing material, to further limit or substantially preclude entry of water droplets and/or water vapor into the housing of the substantially sealed camera module 10.
Circuit board 26 includes a camera mounting circuit board 26a, which is connected to a connector receiving circuit board 26b via a multi-wire ribbon wire or the like (not shown). Camera mounting circuit board 26a is mounted or secured to the base portion 12b of camera portion 12, while connector circuit board 26b is mounted or secured to the base portion 14b of connector portion 14. Camera or image sensor 18 is mounted at a surface of camera circuit board 26a, and is substantially encased at circuit board 26a by camera cover 28 and lens 24 (
Cameras or sensors such as the camera module 10, for example, are now often successfully incorporated in vehicles of various types, improving safety and facilitating the driving experience. One difficulty found in the use of such devices is the tendency of such cameras or sensors to collect dust and dirt, obscuring the images they provide and reducing their utility. This problem has been overcome in the prior art through the provision of spray nozzles adjacent the camera or sensor lens to allow periodic cleaning of the lens. All passenger vehicles contain washer systems incorporating nozzles directing fluid to clean the front windscreen to provide a clear field of vision to the driver. These same vehicles now may also contain additional nozzles to clean the rear window, headlamps, or sensors such as cameras or LIDAR.
An automotive washer system often has multiple branches to reach the various cleaning nozzles, and such a multi-branch system may be supplied with a single fluid reservoir and a dual outlet pump or with multiple reservoirs and two or more similar single or dual outlet pumps. Typically, the pump driving the system is designed and sized to supply fluid for the highest flowrate portion of the system, which normally would be either the front windscreen nozzles or the headlamp nozzles. Consequently, when fluid is demanded at a location such as a camera or sensor cover or lens or at the rear window, where lower target flowrates are desired to conserve fluid, the pump is oversized for the application and generates more pressure than may be necessary for cleaning. This high pressure results in a high flow rate and excessive fluid consumption. Conservation of fluid is desirable on all vehicles, but becomes critical when a vehicle contains multiple nozzles, such as when one or more sensors or objectives are to be washed.
To avoid overuse of the fluid, the flow rate to a low-flow nozzle may be constrained by restricting the size of the fluid outlet. This is undesirable, however, as the likelihood of clogging the nozzle increases in inverse proportion to the size of the nozzle outlet. Additionally, difficulty of manufacturing also increases in inverse proportion to the size of the nozzle outlet, and normal manufacturing tolerances have an increased effect on the performance of smaller nozzles than would be observed on proportionally larger nozzles.
In accordance with the present invention, the system described herein addresses these issues by including a pressure control device or flow regulator in the flow path to a nozzle that only requires a relatively low flow. Numerous types of pressure control devices exist and have been used in other fields, such as in residential plumbing fixtures or irrigation devices, where a consistent flow rate is desired despite fluctuations in system pressure but are not satisfactory in the automotive field, where size and weight restrictions preclude the use of such devices. As illustrated in
In accordance with the invention, and as will be described in detail below, a pressure control device may be incorporated as a separate component anywhere in the system 40, but should not restrict flow to spray nozzles in the primary wash area 66, which may be either the front windscreen nozzles or the headlamp nozzles of a vehicle and which are connected to pump 44 by way of tubing 68. Alternatively, the pressure control device may be integrated into any of the jumper hose components mentioned above, such as the nozzle 50, the check valve 52, the filter 60, or a connector 62 or 64. Commonly, check valves are integrated into nozzles as a single subassembly, but two or more of the foregoing component types could be incorporated into a single device, such as a nozzle integrally containing both a PCD and a check valve, or a filter integrally containing a PCD and a check valve.
Another version of a jumper hose assembly, or washer system, is illustrated at 80 in
As previously described, and as will be further described in detail below, a pressure control device (PCD) may be incorporated as a separate component anywhere in the system 80, but should not be in tube 68 where it would restrict flow to spray nozzles in the primary wash area 66, which may be either the front windscreen nozzles or the headlamp nozzles of a vehicle and which are connected to pump 44 by way of tubing 68. Alternatively, the pressure control device may be integrated into any of the jumper hose components mentioned above, such as the nozzle 50, the check valve 88, the filter 92, or one of the connectors 94, 96 or 98. Furthermore, two or more of the foregoing component types could be incorporated into a single housing, such as a nozzle integrally containing both a PCD and a check valve, or a filter integrally containing a PCD and a check valve.
However, as illustrated in the side perspective view of
The interior chamber 170 (of the inner body portion 144) is open at its downstream end 174 and has an inner diameter sufficient to receive a generally cylindrical filter element 176 through the open end. As illustrated, the downstream end, or outlet 177 of the filter element incorporates a cylindrical extension 178 which receives a pressure control device 180 and positions it immediately below and coaxial with the filter. The interior chamber 172 of the outer body portion 146 has an open upstream end 182 and a diameter sufficient to snugly receive the wall 156 of the inner body portion 144 so that the inner body portion telescopes into the outer body portion. As illustrated in
The upstream end 198 of the inner housing portion 144 is closed by a substantially radially-extending wall 200 which incorporates an axially-extending upstream tubular extension or conduit 202 defining an interior inlet fluid passageway 204 leading to the interior chamber or cavity 170. The exterior surface of the conduit 202 receives a fluid supply tube or hose, such as tube 84 in the example of
The upstream end 198 (the lower end as viewed in
The inner body portion 144 incorporates an outer circumferential sealing ring near its upstream end that engages the inner surface of chamber 172 at rim 238 of the outer body portion 146. In addition, as illustrated in
As best seen in
As noted above, an automotive washer system such as that shown at 40 in
To provide nozzle flow rates that are sufficient to adequately clean a lens without wasting fluid, the pressure control device (PCD) or flow regulator 180 incorporated in filter element 140 may take any of several forms, but in its preferred form, illustrated in
The pressure control device 180 is constructed of an elastomeric material, such as TPV, so that the tabs 310, 312 and 314 are flexible and are configured to have a predictable deformation in response to fluid pressure and flow. The tabs are shown in a rest or fully open state in the Figures, so that the slots and the central aperture, or opening, combine to provide a maximum passage area for fluid passing through the device in the direction of arrow 339 (
As illustrated in
Fluid flow through the filter element of the present invention and thus to the fluidic spray device or devices 50 connected to a jumper hose assembly of the type generally described herein, is controlled by the pressure control device 180 described above. In use, the flexible tabs or flaps bend axially downstream (downwardly as viewed in
For comparison purposes,
According to the present invention, then, an automotive wash system containing a fluidic, shear, or jet nozzle for washing sensors or lens components for automotive camera, LIDAR, LEDAR, radar, other optical sensor devices as well as rear glazing, side view mirror, headlamp, and the like with a supply flow rate of between 1 and 2500 mL/min with a supply pressure of between 1 and 80 psi is fluidly connected through a pressure control device (PCD) or flow regulator, in such a way that flow to the nozzle does not exceed 90% of the nominal flow rate without the PCD for supply pressures between 30 and 60 psi; if desired, the PCD may be selected to limit the system to a lower target flowrate for the same pressure range. As discussed above, in a preferred washer system, a check valve is provided that is less than about 24 inches from a nozzle, and even better, is less than 12 inches away, to insure proper operation of the system. As illustrated in
Having described preferred embodiments of a new and improved lens cleaning system and method, it is believed that other modifications, variations and changes will be suggested to those skilled in the art in view of the teachings set forth herein. For example, the pressure control device is illustrated in its preferred form as a part of a jumper hose filter element; however, it will be understood the pressure device as illustrated may be a stand-alone component included in a jumper hose, or may be incorporated with a component other than a filter, such as with a connector, a check valve, or even a nozzle. It is therefore to be understood that all such variations, modifications and changes are believed to fall within the scope of the appended claims which define the present invention.
This application is a continuation of U.S. Utility application Ser. No. 16/094,896 filed on Oct. 19, 2019 which is a 35 U.S.C. 371 national stage filing of International Application No. PCT/US2017/028363 filed on Apr. 19, 2017, which claims priority to related and commonly owned U.S. provisional patent application No. 62/324,742, filed Apr. 19, 2016, the entire disclosure of which are hereby incorporated herein by reference. This application is also related to commonly owned Published US Application 20160001330, entitled “Integrated automotive system, nozzle assembly and remote control method for cleaning an image sensor's exterior or objective lens surface,” the entire disclosure of which is also incorporated herein by reference, for enablement purposes and to provide context and nomenclature.
| Number | Date | Country | |
|---|---|---|---|
| 62324742 | Apr 2016 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16094896 | Oct 2018 | US |
| Child | 17080007 | US |
