Car knob torque characteristic curve of

Abstract: By analyzing the car knob torque characteristic curve , torque requirements, examples of introductions , made ​​car knob torque characteristics requirements.
Keywords : Vehicle knob ; torque characteristics ; multi-angle knobs ; positioning knob
A car knob introduced mainly rely on car knob to change the gear shaft rotation in order to achieve the purpose of the circuit pass and off . Commonly used in air conditioning and adjustable volume control and so on.
1.1 Classification car knob , divided by mode of operation can be divided into multi-angle type and location type categories . Multi-angle type car Knob : These vehicles knob similar sense of multi-angle potentiometer, mainly by regulating resistor to control the loop current value , then control the product features to achieve , such as car volume control knob . Its main applications are multi- function control gear , such as backlight brightness adjustment , volume control , tone adjustment and other functions, these functions are generally more than 10 stalls in control, so recommended multi-angle type vehicle knob. Positional car knob: Knob type of vehicle positioning sense , generally used in small stalls in control ( 10 files less ) .
1.2 Vehicle knob working logic of the axes in the function , usually up to the right is the positive direction , i.e. in Figure 2 the direction of y + , x + direction . Similarly , consumers are also thinking to operate up to the right direction is increased . Vehicle shall be in accordance with the knob operating habits of consumers is designed to increase clockwise , counterclockwise to decrease , cut down on the increase , right, left less growth .
1.3 Vehicle Concept Car torque characteristics knob Knob torque characteristics , mainly referring to operating comfort . The size should be basically the same moment the knob , the knob rotation torque should not appear in significant changes , should stay the same ; each rotation of the knob in the stationary state and the process should be no significant loosening the knob shaking volume should be basically the same ; knob rotation process should be lightweight , flexible, stalls sense of clear, no tight feeling .
1 ) torque value type vehicle for positioning knob , the general process of torque and stall torque are two requirements ; For multi-angle knob only peak torque requirements.
2 ) peak torque during rotation peak torque of maximum torque values ​​, that mentioned in the text stall torque , torque peaks. The position of the peak point is very important , it will affect the stall feeling. According to experience, this function should peak torque stall angle of total stroke , or 30% of the total at the better.
3 ) intensity knob knob knob intensity control mechanism can withstand without damage the maximum torque value , according to human comfort requirements and the material and structural properties of the product itself , the majority of standards are defined as 2Nm. 2 Introduction 2.1 Typical torque characteristics torque characteristic curve of the test method 2.2 Moment Figure 6 for a vehicle air-conditioning control knob moment diagram testing methods , and in some moment of the knob can not be tested directly in the case , by measuring the F and L can be calculated in a manner contribute torque values. Torque of the formula : F = T / L, test speed : 60 ° / s. 2.3 The Company knob torque requirements following analysis of different companies on the knob torque requirements, including Bonaire , Nissan, Ford, General Motors and other companies related to product requirements.
1) S1 Corporation conditioning controller knob requirements.
2) S2 requirements of multimedia knob shown in Figure 8 .
3) S3 company's multi-angle type vehicle knob general requirements, through the torque formula can be drawn : knobs for different diameters , the peak force stabilized at about 0.5 N , valley force stabilized at about 0.1N .
4) S4 company air conditioning controller knob requirements in Table 2 . By contrast the above criteria can be seen from different companies , each company on the torque requirements are different, especially in multi-angle positioning knob and the knob difference of at least 10 times more. Where S1 torque requirements of the company's largest , into a rotating force of about 10 N , subjective feelings too large. Therefore , the following will be testing different knobs, a combination of its torque subjective evaluation , objective indicators derived recommended torque values.
3 types of vehicles Knob Case Study
3.1 interior light knob torque curve ( positioning type ) for the interior lights knob a stall torque curve , we can see stall torque : 0.11 Nm, smoother curves , torque peaks at 40% to 50% of stroke position so. Subjective evaluation : the operation more comfortable, but turning a long trip before reaching peak torque , peak down to the valley after a quick point , I feel more awkward , I feel bad stalls .
3.2 Volume control knob torque curve Vehicle ( multi-angle type ) without limiting the volume knob angle torque curve, the peak torque is 0.022Nm, as multi-angle knob .
3.3 Mode Selection Auto dial torque curve ( positioning type ) Subjective evaluation : Operation can accept, stall torque is slightly less prominent , with the gap between the moment the process is not very obvious.
3.4 abnormal torque curves ( positioning type ) by testing its torque curve , we can see a comfortable stall torque converter knob 0.15 Nm, while catching knobs test torque curve in the oval painting circle section appears a peak close to 0.2 Nm glitches , where there are tight feeling led knob operation . In addition, some vehicles knob design is unreasonable because torque , resulting in poor operating comfort , such as a car stereo panel , two knobs diameters of 33mm and 26mm, its moments are 0.015Nm. According to Table 1, the large diameter should be smaller than the torque value of the torque value is large in diameter , so that it can obtain a stable operating force . If the same moment , the large diameter knob operating force will be relatively small , this will lead to a sense of no damping operation , reduce customer operating comfort .
4 summarizes the relevant standards by analyzing each company :
1 ) Car knob early in the design should be considered a good choice of multi-angle positioning knob or knobs . In the stalls more, such as volume more than 10 stalls , it is recommended to select multiple angles knob to facilitate fast switching gear .
2 ) Multi-angle peak torque knob recommended as : 0.007 ~ 0.03Nm; different diameters depending on the product , the specific torque values ​​recommended Refer to Table 1 .
3 ) positioning knob stall torque is recommended for : 0.1 ~ 0.2 Nm; For some larger size mechanical knob can be designed to a maximum of not more than 0.5 Nm. Stall torque moment proposed design for the process three times to form a clear shift feeling. For example: a knob stall torque is designed to 0.15Nm, then the process of torque recommended as 0.05Nm.
4 ) stall torque peak torque that is , the best location should be in gear for this feature to adjust the angle of the stroke or the total at 30% . 3.4 assembly verification based on digital to analog to make rapid prototyping parts, assembled in the car simulation , analysis and rational assembly interference and, if unreasonable , then continue to adjust the corresponding structure .
4 summarizes the above design process is based on the plug wire for power distribution box , when the need to design a power distribution box for the bus bar type and PCB power distribution box , the general idea remains the same , there is need for additional attention to the contents of the following aspects .
1 ) Because the bus bar power distribution box and distribution boxes are integrated PCB board part of the vehicle circuit, so in the design process, the need to draw out the power distribution box diagram, this diagram is based on the power distribution map from , the final analysis of the reasonableness of the schematic and reliability.
2 ) in the design of the copper alloy sheet , and PCB board, according to the direction of current flow through , consider copper and tin foil current carrying capacity and overall temperature rise.
3 ) connector ( wiring harness connector and the power distribution box ) the selection and design of distribution boxes in the back of the connector design should select an independent analysis of the current size of each terminal , and finally select the appropriate terminal width . Combined power distribution box and wiring harness , choose the right quantity and specifications of the connector , and finally assembled in the layout considering the convenience . 5 Conclusion After repeated design verification and design changes , according to the project schedule , and finally determine the final distribution box drawings, including distribution boxes , 3D digital to analog , two-dimensional drawings, tooling drawings , assembly drawings, etc. , and then publish the mold Directive . About the latter part of the mold development, mold manufacturing, material selection , etc., will not be further described herein , it should be noted that, in the choice of raw materials, distribution box , you need to ensure that raw materials meet the EU market access for two environmental directives , respectively WEEE ( European Parliament and of the Council on waste electrical and Electronic Equipment Directive case ) and ROHS ( European Parliament and the Council on the restriction of electrical and electronic equipment in the use of certain hazardous Substances Directive case ) .