Method and apparatus for the reduction of washer fluid odor in the passenger compartment of a vehicle

A climate control system including an air controller switchable between fresh air, recirculated air, and partial recirculated air modes is disclosed. The system further includes a control module connected to the controller and a link operatively connecting the washer fluid system and the module. When the washer fluid system is activated, the module switches the controller from the fresh air mode to the recirculated air mode, preventing washer fluid odors from entering the vehicle cabin while the washer fluid system is activated. The module can also selectively switch the air controller between fresh, recirculated, and partial recirculated air modes based on condition inputs. Non-limiting examples of condition inputs include a fog look-up table, wet bulb level, humidity level, air quality level, and temperature level. The module directs the air controller to switch to the fresh air mode based on information generated by one or more of the condition inputs.

TECHNICAL FIELD

The disclosed invention relates generally to the management of washer fluid odors in the passenger compartment of a vehicle. More particularly, the disclosed invention relates to a method and apparatus for reducing the fluid odor in the passenger compartment of a vehicle by automatically switching the climate control system to recirculation when the windshield washer is activated.

BACKGROUND OF THE INVENTION

Windshield washer fluid for use in conjunction with windshield wipers has been available on vehicles at least since the mid-1930s. While available in a broad variety of formulations, most windshield washer fluid used today comprises about 40% methanol alcohol which is proven highly effective in eliminating insect remains from the vehicle windshield. (As an alternative to methanol alcohol some windshield washer fluid compositions use ethanol or ethylene glycol.) Additional ingredients include a blue dye from a powder and, in colder climates, methylated spirits to lower the freezing point of the washer fluid. Regardless of the formulation, most windshield washer fluids have an unpleasant odor.

In addition to improved methods for maintaining a clean windshield, other developments in vehicle passenger comfort have taken place concurrently, including ventilation systems. Today's modern heating, ventilation and air conditioning system (HVAC) system includes a variety of operator modes, including “fresh air” and “recirculation” modes. The fresh air mode is based on a system in which fresh air is brought from the outside into the vehicle. In most vehicles the fresh air intake is located between the trailing edge of the vehicle's engine hood and the leading edge of the vehicle's windshield.

Placement of the fresh air intake between the vehicle's engine hood and windshield has the advantage of orienting the intake proximate the vehicle's instrument panel and associated duct system. However, placement of the fresh air intake in this area also results in the fresh air intake being close to the windshield washer fluid spray nozzles. If the windshield washer fluid is used by the operator in conjunction with the windshield wipers while the HVAC is in the fresh air mode, very commonly the odor of the windshield washer fluid enters the vehicle cabin.

The situation described above may arguably be corrected if the vehicle operator is able to manually select the recirculation mode over the fresh air mode prior to engaging the windshield washer fluid, returning to the fresh air mode after the windshield has been cleaned. However, this approach is impractical and unlikely to be used often if at all.

As in so many areas of vehicle technology there is always room for improvement related to the use and operation of windshield washer fluid.

SUMMARY OF THE INVENTION

The disclosed invention overcomes the problems of known windshield washer fluid systems by providing a climate control system that includes an air controller switchable between a fresh air mode, a recirculated air mode, and a partial recirculated air mode. The system further includes a control module connected to the air controller and a link operatively connecting the washer fluid system and the control module. In its most fundamental form when the washer fluid system is activated the control module switches the air controller from the fresh air mode to the recirculated air mode. In this way washer fluid odors are prevented from entering the vehicle cabin while the washer fluid system is activated.

The control module can selectively switch the air controller between the fresh air, recirculated, and partial recirculated air modes. Selection is based on condition inputs. Non-limiting examples of condition inputs include a fog look-up table (or some other data source), wet bulb level, humidity level, air quality level, and temperature level. The control module directs the air controller to switch to the fresh air mode based on information generated by one or more of the condition inputs. In addition, the control module further includes a delay timer to delay returning from the recirculated mode to the fresh air mode following deactivation of the washer fluid system based on one or more of the condition inputs.

The climate control system of the disclosed invention further includes a multi-speed blower connected to the control module. The control module can switch the multi-speed blower to a lower speed in the event that switching to the recirculated air mode from either the fresh air mode or the partial recirculated air mode is not possible based on one or more of the inputs. In this way the degree of windshield washer fluid odor is minimized.

The delay timer may also function to delay for a selected time returning from the recirculated mode to the fresh air mode following deactivation of the washer fluid system.

The above advantages and other advantages and features will be readily apparent from the following detailed description of the preferred embodiments when taken in connection with the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following figures, the same reference numerals will be used to refer to the same components. In the following description, various operating parameters and components are described for different constructed embodiments. These specific parameters and components are included as examples and are not meant to be limiting.

In general, the disclosed invention provides a climate control system that is able to automatically switch the climate control system from the fresh air mode to the recirculation mode when the windshield washer fluid spray is activated. The climate control system is maintained in the recirculation mode until sufficient time has elapsed or if higher priority conditions require switching back to fresh air.

If a windscreen operation is in progress, additional conditions could be evaluated to determine if temporary recirculation or partial recirculation could be used or if return to full fresh air has is required. These conditions include but are not limited to evaluation of fog look-up tables a fog look-up table (or some other data source), wet bulb level, humidity level, air quality level, and temperatures. If the conditions require partial recirculation or full fresh air and switching to full recirculation is not possible, reduction of blower level may be used to minimize the levels of odor transfer to the cabin during windshield washer mode.

Referring toFIG. 1, an automotive vehicle, generally illustrated as10, is provided with the climate control system of the disclosed invention. The vehicle10includes an engine hood12located at a forward extremity of the vehicle10and a windshield14sloped upwardly and rearwardly from the engine hood12. Between the engine hood12and the leading edge of the windshield14is disposed a cowling16that functions to draw fresh air into the climate control system or the heating, ventilation and air conditioning system (HVAC)18of the vehicle10. Windshield washer fluid sprayers, of which one sprayer20is visible, are fitted to the vehicle10as is known in the art.

The vehicle10, the engine hood12, the windshield14, the cowling16, the windshield washer fluid sprayer20, and the fresh air intake20as shown are for illustrative purposes only and are not intended as being limiting as it is understood that each of these components may be varied in overall shape and size.

The cowling16is in fluid communication with fresh air intake22of the HVAC18. An airflow controlling gate24is pivotably provided adjacent the fresh air intake22as is known in the art for regulating the intake of fresh air into the HVAC18. The HVAC18further includes a multi-speed blower26. The HVAC18is operated by a controller such as a control module28that incorporates an air mode controller and a timer.

Referring toFIG. 2, the HVAC18and the control module28are illustrated in simplified block diagram format. The control module28is adapted to receive a number of condition inputs related to ambient conditions. The condition inputs provide a basis upon which the control module28determines which of the fresh, partial recirculated air, or recirculated air modes is to be selected at any given time.

The condition inputs may be several but examples of selective condition inputs are illustrated inFIG. 2and include, without limitation, a fog look-up table30(or some other data source), a wet bulb level sensor32, a humidity level sensor34, an air quality level sensor36, and a temperature level sensor38. Other condition inputs may be incorporated as well.

Methods of operating the control module28of the climate control system of the disclosed invention are set forth inFIG. 3which is a flow chart illustrating operation of the system. Referring thereto, at step100, the vehicle10is started. At step102an inquiry is made as to whether or not the windshield washer is activated. Optionally, an inquiry may also be made if the vehicle is in reverse. This optional inquiry is made in order to prevent unwanted exhaust gas from entering the vehicle while the driver is backing up to vehicle. If the windshield washer is not activated or if the vehicle is not in reverse then no further steps are taken and activity is at an end104. However, if the windshield washer is found to be activated or if the vehicle is not in reverse, then an inquiry is made at step106as to whether or not the control system is in either the partial recirculation or fresh air mode. If the system is in neither of these modes then no further steps are taken and activity is again at an end104.

However, if at step106it is found that the control system is in either the partial recirculation or fresh air mode, then the timer is started at step108. With the timer108running, an inquiry is made at step110as to whether or not the climate control is in windscreen mode. If the response to that inquiry is “no,” then the system is set at step112to operate in recirculation mode which itself is timed incrementally at step114. The fresh air mode may also be switched to the full recirculation mode in the event that the vehicle is in put into reverse gear, thereby eliminating any risk of exhaust gases from entering the vehicle cabin. Thereafter an inquiry is made at step116as to whether or not the timer is expired. If the timer is expired then the system returns to normal operation at step118.

If, on the other hand, the timer is found not to have expired at step116, then an inquiry is again made at step110as to whether or not the climate control is in windscreen mode. If the response to that inquiry at step110is “no” then the sequence of events described above is followed. In the event that the inquiry made at step110is “yes,” then a determination of fogging sensitivity is made at step120based on condition inputs122. As noted above with respect toFIG. 2, condition inputs include one or more inputs selected from the group consisting of a fog look-up table (or some other data source), the wet bulb level, the humidity level, the air quality level, and the temperature level.

Once fogging sensitivity is determined at step120, then an inquiry is made at step124as to whether or not the climate control system can be operated in recirculation mode. If the response to that inquiry is “yes,” then instructions are given for the system to operate in recirculation mode at step112and the sequence of events described above is followed.

On the other hand, if the response to the inquiry at step124is “no,” then an inquiry is made at step126whether or not the climate control system can be operated in partial recirculation mode. If it is found at step126that the climate control system can be operated in partial recirculation mode, then the system is set at step128to operate in partial recirculation mode which, as with the recirculation mode of step112, is timed incrementally at step114. As set forth above, an inquiry is thereafter made at step116as to whether or not the timer is expired. If the timer is expired then the system returns to normal operation at step118but if the timer is not expired then an inquiry is made at step110as to whether or not the climate control is in the windscreen mode. Based on the response to the inquiry at step110one of the sequences previously described will be followed.

If it is found at step126that the climate control system cannot be operated in partial recirculation mode, then an inquiry is made at step129as to whether or not the blower speed can be reduced. If the response at step129is “yes,” then the blower speed is reduced at step130.

If at step129it is found that the blower speed cannot be reduced, then the system returns to normal operation at step118.

The disclosed invention as set forth above overcomes the challenges faced by known windshield washer fluid and climate control systems for vehicles by either eliminating or significantly reducing the amount of windshield washer fluid odor present in the vehicle. However, one skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims.