DESC:DESCRIPTION
TECHNICAL FIELD
The present subject matter generally relates to heating, ventilation, and air conditioning control (HVAC) systems and more specifically towards a control HVAC switch in a vehicle.
BACKGROUND
Today’s automobiles or vehicles come equipped with various designs of heating, ventilation, and air conditioning (HVAC) systems for climate control of vehicles. Most of the HVAC systems operate the same way, i.e., by circulating hot and/or cool air in an occupant cabin of the vehicle. However, these HVAC systems differ in their external design and primarily in the design of switches to control operations of the HVAC systems. There are generally three types of switches: (a) knob; (b) button; and (c) lever. A knob is a rounded dial that is turned to control the settings of air conditioner and heater. For instance, the dial may be turned to point towards a certain number in order to control the speed of a blower or fan. The knob is the most common temperature control switch provided on a dashboard of the vehicle. The button may be press/touch control button that is pressed/touched to control an operation of the air conditioner and the heater. The lever is a type of a switch that involves moving a small handle from a first direction to a second direction and then again to first direction to set desired temperature settings in the vehicle. For example, the handle can be moved from up to down or from left to right, and then back. Typically, the switches are provided in a control HVAC switch for controlling operations of the HVAC systems.
Presently, separate button is provided on the control HVAC switch to switch ON the air conditioning inside the vehicle. This button is marked as A/C switch. In operation, a passenger presses the A/C switch to power ON the air conditioning and thereafter uses one or more of the switches, i.e., the rotary knob or the button, provided on the control HVAC switch to select vent flow, fan blow speed, and temperature control for climate control in the vehicle. The presence of separate button increases complexity of mechanical coupling inside the control HVAC switch.
Thus, there is a need for improvement in the control HVAC switch.
SUMMARY
The present subject matter as embodied and broadly described herein discloses a control heating, ventilation, and air conditioning (HVAC) switch in a vehicle.
In accordance with an embodiment of the present subject matter, the control HVAC switch comprises an air supply temperature knob adapted to be rotated to operate in a first mode of operation and a second mode operation. The control HVAC switch further comprises an interfacing-circuit. The interfacing-circuit comprises a detector switch adapted to switch between a first position and a second position, and is operatively connected with the air supply temperature knob and an electronic control unit. Accordingly, in the first mode of operation, a first rotation of the air supply temperature knob switches the detector switch from the first position to the second position to provide a “SWITCH ON” signal to the electronic control unit. The “SWITCH ON” signal is indicative of switching an AC function of the vehicle to an “ON state”. In the second mode of operation, at least one second rotation of the air supply temperature knob controls a temperature in the vehicle.
The advantages of the present invention include, but not limited to, elimination of a separate A/C switch to switch ON the air conditioning inside the vehicle by synchronizing the operation of the separate A/C switch with the air supply temperature knob. Thus, the control HVAC switch has reduced mechanical coupling complexity. Further, manufacturing costs of the control HVAC switch are considerably reduced.
These and other aspects, as well as advantages, will be more clearly understood from the following description taken in conjugation with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
To further clarify advantages and aspects of the invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings in accordance with various embodiments of the invention, wherein:
Figure 1 illustrates an isometric view of a control HVAC heating ventilation and air conditioning (HVAC) switch in a vehicle, in accordance with an embodiment of the present subject matter.
Figure 2 illustrates an exploded view of the control HVAC switch, in accordance with the embodiment of the present subject matter.
Figures 3(a) and 3(b) illustrate an internal mechanism the control HVAC switch, in accordance with the embodiment of the present subject matter.
Figures 4(a) and 4(b) illustrate a working of an air supply temperature knob in the control HVAC switch, in accordance with the embodiment of the present subject matter.
Figure 5 explains internal mechanism of the control HVAC switch, in accordance with the embodiment of the present subject matter
It may be noted that to the extent possible, like reference numerals may have been used to represent like elements in the drawings. Further, those of ordinary skill in the art will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of aspects of the invention. Furthermore, one or more elements may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.
DETAILED DESCRIPTION
It should be understood at the outset that although illustrative implementations of the embodiments of the present disclosure are illustrated below, the present subject matter may be implemented using any number of techniques, whether currently known or in existence. The present disclosure should in no way be limited to the illustrative implementations, drawings, and techniques illustrated below, including the exemplary design and implementation illustrated and described herein, but may be modified within the scope of the appended claims along with their full scope of equivalents.
The term “some” as used herein is defined as “none, or one, or more than one, or all.” Accordingly, the terms “none,” “one,” “more than one,” “more than one, but not all” or “all” would all fall under the definition of “some.” The term “some embodiments” may refer to no embodiments or to one embodiment or to several embodiments or to all embodiments. Accordingly, the term “some embodiments” are defined as meaning “no embodiment, or one embodiment, or more than one embodiment, or all embodiments.”
The terminology and structure employed herein is for describing, teaching and illuminating some embodiments and their specific features and elements and does not limit, restrict or reduce the scope of the claims or their equivalents.
More specifically, any terms used herein such as but not limited to “includes,” “comprises,” “has,” “consists,” and grammatical variants thereof do NOT specify an exact limitation or restriction and certainly do NOT exclude the possible addition of one or more features or elements, unless otherwise stated, and furthermore must NOT be taken to exclude the possible removal of one or more of the listed features and elements, unless otherwise stated with the limiting language “MUST comprise” or “NEEDS TO include.”
Whether or not a certain feature or element was limited to being used only once, either way, it may still be referred to as “one or more features” or “one or more elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “one or more” or “at least one” feature or element do NOT preclude there being none of that feature or element, unless otherwise specified by limiting language such as “there NEEDS to be one or more . . . ” or “one or more element is REQUIRED.”
Unless otherwise defined, all terms, and especially any technical and/or scientific terms, used herein may be taken to have the same meaning as commonly understood by one having an ordinary skill in the art.
Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements presented in the attached claims. Some embodiments have been described for the purpose of illuminating one or more of the potential ways in which the specific features and/or elements of the attached claims fulfill the requirements of uniqueness, utility, and non-obviousness.
Use of the phrases and/or terms such as but not limited to “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or variants thereof do NOT necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and/or elements may be described herein in the context of only a single embodiment, or alternatively in the context of more than one embodiment, or further alternatively in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.
Any particular and all details set forth herein are used in the context of some embodiments and therefore should NOT be necessarily taken as limiting factors to the attached claims. The attached claims and their legal equivalents can be realized in the context of embodiments other than the ones used as illustrative examples in the description below.
Figure 1 illustrates an isometric view of a control HVAC heating ventilation and air conditioning (HVAC) switch 100 in a vehicle (not shown in the figure), in accordance with an embodiment of the present subject matter. In an implementation, the vehicle is a passenger car. The control HVAC switch 100 comprises of a front panel 102. The front panel 102 is an aesthetic portion of the control HVAC switch 100 that covers the functional parts of the control HVAC switch 100. The front panel 102 is disposed on a dashboard of the vehicle and includes various buttons and knobs for controlling one or more operations of the control HVAC switch 100.
As such, the control HAVC switch 100 includes fresh air selection button 104 and recirculated air selection button 106 to enable selection of type of air inside the vehicle. The control HAVC switch 100 also includes an F&R slider knob 108. The F&R slider knob 108 is coupled with a blower switch (not shown in the figure) and acts as an interface between a user and the blower switch to control a speed of blower (not shown in the figure). The control HVAC switch 100 may include other switches/ buttons (represented by polygons) to control further operations of the control HVAC switch 100 as known in the art.
The control HVAC switch 100 further includes three rotary knobs, viz., an air distribution knob 110, a fan speed knob 112, and an air supply temperature knob 114. The rotation degrees for each of the rotary knobs may be predefined or maybe along an entire circumference of the respective knobs. Further, a position of the rotary knob with respect to its circumference may be predefined for a particular function associated with cooling or heating inside the vehicle.
The air distribution supply knob 110 is adapted to be rotated at angular intervals to point to any one of intermediate positions. The intermediate positions lead to a selection of one or more air distribution outlets from amongst a plurality of air distribution outlets inside the vehicle. The plurality of air distribution outlets may include front nozzles of the dashboard and foot space nozzles. The plurality of air distribution outlets may be indicated on the air distribution supply knob 110 by way of icons or symbol.
As such, in an example, the air distribution supply knob 110 may be rotated at angular interval to point to the intermediate position that leads to distribution of air only through the front nozzles of the dashboard. In another example, the air distribution supply knob 110 may be rotated at angular interval to point to the intermediate position that leads to distribution of air through the front nozzles of the dashboard and the foot space nozzles. In another example, the air distribution supply knob 110 may be rotated at angular interval to point to the intermediate position that leads to distribution of air only through the foot space nozzles.
Further, the fan speed knob 112 is adapted to be rotated to change a rate of air flowing through the one or more air distribution outlet selected from amongst the plurality of air distribution outlets via the air distribution supply knob 110. The fan speed knob 112 is coupled with a fan in the vehicle via the blower switch. Consequently, a rotation of the fan speed knob 112 leads to an adjustment of a speed of the fan, thereby changing the rate of air. The fan speed knob 112 may be rotated at angular intervals up to 120 degrees and includes four-speed stages. The four-speed stages may be indicated by way of numerals 1, 2, 3, and 4 on the fan speed knob 112. The fan speed knob 112 also includes an OFF position indicated by way of numeral 0 on the fan speed knob 112.
Further, the air supply temperature knob 114 is adapted to be rotated to adjust air temperature inside the vehicle. The air supply temperature knob 114 may usually have regions to control the temperature for cold air and regions to control the temperature for warm. Such regions are generally colored distinctively for demarcation, for example, a blue colored region is indicative of temperature control for cool air and a red colored region is indicative of temperature control for warm air. Each of the regions may extend over half of the total angle of approximately 270 degrees. The air supply temperature knob 114 may operatively be in connection with a temperature mixing valve.
Further, the air supply temperature knob 114 includes marked areas indicative of different stages for temperature controls, starting from an OFF position to a minimum temperature setting to a maximum temperature setting. The different stages can be indicated by different sized polygons and may include 18 stages. The air supply temperature knob 114 can be rotated up to a maximum angular rotation along a circumference of the knob 114 for setting the maximum temperature for warm air supply inside the vehicle. Typically, the air supply temperature knob 114 is kept at OFF position for cooling function or AC function of an air conditioner (AC) in vehicle. Conventionally, the AC function is turned ON by pressing a separate switch button (not shown in Figure 1) and thereafter controlling the speed of the fan by rotating the fan speed knob 112. The present subject matter provides a solution wherein the separate press switch button conventionally provided on the dashboard for turning the AC function is eliminated.
Accordingly, in accordance with the embodiment of the present subject matter, the cooling function or the AC function is synchronized with the air supply temperature knob 114. To this end, the air supply temperature knob 114 is adapted to be rotated to operate in a first mode of operation and a second mode operation. The first mode of operation controls turning ON or OFF of the AC function. As such, in the first mode of operation, a first rotation of the air supply temperature knob 114 turns ON the AC function of the vehicle and a second rotation of the air supply temperature knob 114 turns OFF the AC function of the vehicle. The AC function is switched/turned ON by achieving a small interval of rotation of the air supply temperature knob 114 so as to point away from the OFF position. The AC function is switched/turned OFF by achieving the small interval of rotation of the air supply temperature knob 114 so as to point towards the OFF position. Thus, a small rotation of the air supply temperature knob 114 switches ON/ switches OFF the AC function as opposed to being kept at OFF position while a separate button is pressed to switch ON/ switch OFF the AC.
The synchronization of the AC function is achieved with the help of a detector switch (not shown in the Figure 1) which is in normally closed (NC) press condition. The detector switch is operated by a cap case (not shown in the Figure 1) assembled on a temperature shaft (not shown in the Figure 1). The working of the detector switch is described with reference to Figure 2, Figures 3(a) and 3(b), and Figures 4(a) and 4(b).
Figure 2 illustrates an exploded view of the control HVAC switch 100, in accordance with an embodiment of the present subject matter. Referring to Figure 2, the control HVAC switch 100 includes an interfacing-circuit 200, also referred to as printed circuit board (PCB CP). The interfacing-circuit 200 completes the internal circuit of the control HVAC switch 100.
The control HVAC switch 100 also includes a temperature shaft 202, also referred to as ‘temp shaft’. The temperature shaft 202 is operably connected with the air supply temperature knob 114 and adapted to be rotated by the rotation of the air supply temperature knob 114 in the first mode of operation. The control HVAC switch 100 also includes a cap case 204 mounted on the temperature shaft 202. The cap case 204 is operably connected with the detector switch.
In addition, some of the various parts of the control HVAC switch 100 include:
• the panel 102;
• the F&R slider knob 108;
• the three rotary knobs, viz., the air distribution knob 110, the fan speed knob 112, and the air supply temperature knob 114;
• a shaft 206;
• a gear 208 to synchronize with the shaft 206 and to operate a mode cable;
• a light guide 210;
• a cap-light guide 212;
• a dummy knob 214 operably coupled with the temperature shaft 202 and the light guide 210;
• a lever 216;
• a slider 218;
• a blower switch 220; and
• a body 222 that holds the above parts of the control HVAC switch 100.
Figures 3(a) and 3(b) illustrate an internal mechanism the control HVAC switch 100, in accordance with the embodiment of the present subject matter. Accordingly, the interfacing-circuit 200 comprises a detector switch 300 adapted to switch between a first position and a second position. The detector switch 300 is operatively connected with the air supply temperature knob 114 and an electronic control unit (not shown in Figure 3). The detector switch 300 is in normally closed (NC) press condition with the cap case 204 assembled on the temperature shaft 202. The first position of the detector switch 300 corresponds to detent of the detector switch 300 being engaged within the cap case 204, as illustrated in Figure 3(a). The second position of the detector switch 300 corresponds to the detent being released out of the cap case 204, as illustrated in Figure 3(b).
Figures 4(a) and 4(b) illustrate a working of the air supply temperature knob 110 in the control HVAC switch 100, in accordance with the embodiment of the present subject matter. As such, referring to Figure 4(a), the air supply temperature knob 114 is at OFF position initially. At the OFF position, as illustrated by Figure 3(a), the detector switch 300 is in press condition (normally closed) which is achieved by the cap case 204 by way of making a press contact with the detector switch 300.
Referring to Figure 4(b), in the first mode of operation, the first rotation of the air supply temperature knob 114 moves the air supply temperature knob 114 away from the OFF position. As such, referring to Figure 3(b), the first rotation of the air supply temperature knob 114 rotates the temperature shaft 202 to release the detent out of the cap case 204. This results in switching the detector switch 300 from the first position to the second position to provide a “SWITCH ON” signal to the electronic control unit. The “SWITCH ON” signal is indicative of switching the AC function of the vehicle to an “ON” state.
In reverse operation, in the first mode of operation, the second rotation of the air supply temperature knob 114 moves the air supply temperature knob 114 towards the OFF position, as illustrated in Figure 4(a). As such, the second rotation of the air supply temperature knob 114 rotates the temperature shaft 202 to engage the detent within the cap case 204. This results in switching the detector switch 300 from the second position to the first position, as illustrated in Figure 3(a), to provide a “SWITCH OFF” signal to the electronic control unit. The “SWITCH OFF” signal is indicative of switching the AC function of the vehicle to an “OFF state”.
Figure 5 explains the internal mechanism of the control HVAC switch 100 in relation to the positioning of the cap case 204 with respect to the detector switch 300 fixed on the interfacing-circuit 200. The section AA marked in Figure 5 explains the position of cap case 204 with respect to the detector switch 300 fixed on the interfacing-circuit 200 at each position.
Thus, the control HVAC switch 100 eliminates the requirement of a separate AC switch button to switch ON and switch OFF the AC cooling function in the vehicle by using the same switch, by way of the air supply temperature knob 114 to operate the positions of the AC switch in first mode of operation.
Further, in accordance with the present subject matter, the second mode of operation of the air supply temperature knob 114 is temperate setting mode for the AC function after the AC function is switched/turned ON by rotating the air supply temperature knob 114 away from the OFF position. In the second mode of operation, at least one further rotation of the air supply temperature knob 114 controls a temperature in the vehicle.
To this end, the interfacing-circuit 200 comprises a circular carbon track (not shown in the figure) having a plurality of interconnected electrical-resistors for defining a pre-defined resistance within the interfacing circuit 200. The carbon track is a circular type track and is operably connected with the fan speed knob 112. The carbon track undergoes a change in resistance based on a rotation of the fan speed knob 112. In addition, the fan speed knob 112 is operatively connected with the air supply temperature knob 114. The fan speed knob 112 indicates a minimum rate of air flow during the first mode of operation of the air supply temperature knob 114.
In the second mode of operation, the at least one second rotation of the air supply temperature knob 114 and the rotation of the fan speed knob 112 control the temperature in the vehicle. The rotation of the fan speed knob 112 changes a resistance on the carbon track. The change in resistance provides a different output voltage to the electronic control unit. In response, the electronic control unit controls the rate of air flow. By way of an example, in the interfacing circuit 200, the carbon track provides a signal to the electronic control unit for cooling from a minimum value (marked as ‘min’ on the air supply temperature knob 114 at one end) to the maximum value (marked as ‘max’ on the air supply temperature knob 114 at the other end), and vice versa. The carbon track thus provided allows controlling the cooling temperature in the vehicle eliminating the requirement of a separate mechanical coupling inside the body of the control HVAC switch 100 to control the same.
Thus, the control HVAC switch 100 controls the cooling temperature in the second mode of operation of the air supply temperature knob 114. The air supply temperature knob 114 synchronized with the cooling function is a low-cost durable switch and eliminates complex mechanical coupling inside the body of the switch.
While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.
While certain present preferred embodiments of the invention have been illustrated and described herein, it is to be understood that the invention is not limited thereto. Clearly, the invention may be otherwise variously embodied, and practiced within the scope of the claims that follow.

,CLAIMS:WE CLAIM:
1. A control heating, ventilation, and air conditioning (HVAC) switch in a vehicle, the control HVAC switch comprising:
- an air supply temperature knob adapted to be rotated to operate in a first mode of operation and a second mode operation; and
- an interfacing-circuit comprising
- a detector switch adapted to switch between a first position and a second position, and operatively connected with the air supply temperature knob and an electronic control unit; and
- wherein:
- in the first mode of operation, a first rotation of the air supply temperature knob switches the detector switch from the first position to the second position to provide a “SWITCH ON” signal to the electronic control unit, the “SWITCH ON” signal being indicative of switching an AC function of the vehicle to an “ON state”; and
- in the second mode of operation, at least one further rotation of the air supply temperature knob controls a temperature in the vehicle.

2. The control HVAC switch as claimed in claim 1, wherein in the first mode of operation, a second rotation of the air supply temperature knob switches the detector switch from the second position to the first position to provide a “SWITCH OFF” signal to the electronic control unit the “SWITCH OFF” signal being indicative of switching the AC function of the vehicle to an “OFF state”

3. The control HVAC switch as claimed in claim 2, further comprises:
a temperature shaft operably connected with the air supply temperature knob and adapted to be rotated by the rotation of the air supply temperature knob in the first mode of operation; and
a cap case mounted on the temperature shaft and operably connected with the detector switch.

4. The control HVAC switch as claimed in claim 3, wherein the first position of the detector switch corresponds to detent of the detector switch being engaged within the cap case and the second position of the detector switch corresponds to the detent being released out of the cap case.

5. The control HVAC switch as claimed in claim 4, wherein the first rotation of the air supply temperature knob rotates the temperature shaft to release the detent out of the cap case.

6. The control HVAC switch as claimed in claim 4, wherein the second rotation of the air supply temperature knob rotates the temperature shaft to engage the detent within the cap case.

7. The control HVAC switch as claimed in claim 1, further comprises:
- a fan speed knob adapted to be rotated to change a rate of air flowing through one or more air distribution outlets selected from amongst a plurality of air distribution outlets in the vehicle and operably connected with the air supply temperature knob, wherein the fan speed knob indicates a minimum rate of air flow during the first mode of operation of the air supply temperature knob.

8. The control HVAC switch as claimed in claim 7, wherein the interfacing-circuit further comprises:
- a circular carbon track having a plurality of interconnected electrical-resistors for defining a pre-defined resistance within the interfacing circuit, the carbon track being operably connected with the fan speed knob, wherein the carbon track undergoes a change in resistance based on a rotation of the fan speed knob.

9. The control HVAC switch as claimed in claim 8, wherein in the second mode of operation, the at least one second rotation of the air supply temperature knob and the rotation of the fan speed knob control the temperature in the vehicle.