小网站 大容量 大智慧
当前位置:首页 >> 文学研究 >>


The overview of automobile air conditioner

Today, as we drive our automobiles, a great many of us, can enjoy the same comfort levels that we are accustomed to at home and at work. With the push of a button or the slide of a lever, we make the seamless transition from heating to cooling and back again without ever wondering how this change occurs. That is, unless something goes awry. (Article Continues below) Since the advent of the automotive air conditioning system in the 1940's, many things have undergone extensive change. Improvements, such as computerized automatic temperature control (which allow you to set the desired temperature and have the system adjust automatically) and improvements to overall durability, have added complexity to today's modern air conditioning system. Unfortunately, the days of "do-it-yourself" repair to these systems, is almost a thing of the past. To add to the complications, we now have tough environmental regulations that govern the very simplest of tasks, such as recharging the system with refrigerant R12 commonly referred to as Freon. (Freon is the trade name for the refrigerant R-12, that was manufactured by DuPont). Extensive scientific studies have proven the damaging effects of this refrigerant to our ozone layer, and its manufacture has been banned by the U.S. and many other countries that have joined together to sign the Montreal Protocol, a landmark agreement that was introduced in the 1980's to limit the production and use of chemicals known to deplete the ozone layer. Now more than ever, your auto mechanic is at the mercy of this new environmental legislation. Not only is he required to be certified to purchase refrigerant and repair your air conditioner, his shop must also incur the cost of purchasing expensive dedicated equipment that insures the capture of these ozone depleting chemicals, should the system be opened up for repair. Simply put, if your mechanic has to spend more to repair your vehicle - he will have to charge you more. Basic knowledge of your air conditioning system is important, as this will allow you to make a more informed decision on your repair options. Should a major problem arise from your air conditioner, you may encounter new terminology. Words like "retrofit" and "alternative refrigerant" are now in your mechanics glossary. You may be given an option of "retrofitting", as opposed to

merely repairing and recharging with Freon. Retrofitting involves making the necessary changes to your system, which will allow it to use the new industry accepted, "environmentally friendly" refrigerant, R-134a. This new refrigerant has a higher operating pressure, therefore, your system, dependant on age, may require larger or more robust parts to counter its inherent high pressure characteristics. This, in some cases, will add significantly to the final cost of the repair. And if not performed properly, may reduce cooling efficiency which equates to higher operating costs and reduced comfort. Vehicles are found to have primarily three different types of air conditioning systems. While each of the three types differ, the concept and design are very similar to one another. The most common components which make up these automotive systems are the following: COMPRESSOR, CONDENSER, EVAPORATOR, ORIFICE TUBE, THERMAL EXPANSION VALVE , RECEIVER-DRIER, ACCUMULATOR. serve the same purpose. Accumulator, but not both. For more information on Air Conditioning, check out The Automotive Air Conditioning Information Server COMPRESSOR Commonly referred to as the heart of the system, the compressor is a belt driven pump that is fastened to the engine. It is responsible for compressing and transferring refrigerant gas. The A/C system is split into two sides, a high pressure side and a low pressure side; defined as discharge and suction. Since the compressor is basically a pump, it must have an intake side and a discharge side. The intake, or suction side, draws in refrigerant gas from the outlet of the evaporator. In some cases it does this via the accumulator. Once the refrigerant is drawn into the suction side, it is compressed and sent to the condenser, where it can then transfer the heat that is absorbed from the inside of the vehicle. CONDENSER This is the area in which heat dissipation occurs. The condenser, in many cases, will have much the same appearance as the radiator in you car as the two have very similar functions. The condenser is designed to radiate heat. Its location is usually in Note: if your car has an Orifice tube, it will not have a Thermal Expansion Valve as these two devices Also, you will either have a Receiver-Dryer or an


front of the radiator, but in some cases, due to aerodynamic improvements to the body of a vehicle, its location may differ. Condensers must have good air flow anytime the system is in operation. On rear wheel drive vehicles, this is usually accomplished by taking advantage of your existing engine's cooling fan. On front wheel drive vehicles, condenser air flow is supplemented with one or more electric cooling fan(s). As hot compressed gasses are introduced into the top of the condenser, they are cooled off. As the gas cools, it condenses and exits the bottom of the condenser as a high pressure liquid. EVAPORATOR Located inside the vehicle, the evaporator serves as the heat absorption component. The evaporator provides several functions. Its primary duty is to remove heat from the inside of your vehicle. A secondary benefit is dehumidification. As warmer air travels through the aluminum fins of the cooler evaporator coil, the moisture contained in the air condenses on its surface. Dust and pollen passing through stick to its wet surfaces and drain off to the outside. On humid days you may have seen this as water dripping from the bottom of your vehicle. Rest assured this is perfectly normal. The ideal temperature of the evaporator is 320 Fahrenheit or 00 Celsius. Refrigerant enters the bottom of the evaporator as a low pressure liquid. The warm air passing through the evaporator fins causes the refrigerant to boil (refrigerants have very low boiling points). As the refrigerant begins to boil, it can absorb large amounts of heat. This heat is then carried off with the refrigerant to the outside of the vehicle. Several other components work in conjunction with the evaporator. As mentioned above, the ideal temperature for an evaporator coil is 320 F. Temperature and pressure regulating devices must be used to control its temperature. While there are many variations of devices used, their main functions are the same; keeping pressure in the evaporator low and keeping the evaporator from freezing; A frozen evaporator coil will not absorb as much heat. PRESSURE REGULATING DEVICES Controlling the evaporator temperature can be accomplished by controlling refrigerant pressure and flow into the evaporator. Many variations of pressure regulators have been introduced since the 1940's. Listed below, are the most commonly found. ORIFICE TUBE The orifice tube, probably the most commonly used, can be found in most GM and Ford models. It is located in the inlet tube of the evaporator, or in the liquid line,


somewhere between the outlet of the condenser and the inlet of the evaporator. This point can be found in a properly functioning system by locating the area between the outlet of the condenser and the inlet of the evaporator that suddenly makes the change from hot to cold. You should then see small dimples placed in the line that keep the orifice tube from moving. Most of the orifice tubes in use today measure approximately three inches in length and consist of a small brass tube, surrounded by plastic, and covered with a filter screen at each end. It is not uncommon for these tubes to become clogged with small debris. While inexpensive, usually between three to five dollars, the labor to replace one involves recovering the refrigerant, opening the system up, replacing the orifice tube, evacuating and then recharging. With this in mind, it might make sense to install a larger pre filter in front of the orifice tube to minimize the risk of of this problem reoccurring. Some Ford models have a permanently affixed orifice tube in the liquid line. These can be cut out and replaced with a combination filter/orifice assembly. THERMAL EXPANSION VALVE Another common refrigerant regulator is the thermal expansion valve, or TXV. Commonly used on import and aftermarket systems. This type of valve can sense both temperature and pressure, and is very efficient at regulating refrigerant flow to the evaporator. Several variations of this valve are commonly found. Another example of a thermal expansion valve is Chrysler's "H block" type. This type of valve is usually located at the firewall, between the evaporator inlet and outlet tubes and the liquid and suction lines. These types of valves, although efficient, have some disadvantages over orifice tube systems. Like orifice tubes these valves can become clogged with debris, but also have small moving parts that may stick and malfunction due to corrosion. RECEIVER-DRIER The receiver-drier is used on the high side of systems that use a thermal expansion valve. This type of metering valve requires liquid refrigerant. To ensure that the valve gets liquid refrigerant, a receiver is used. The primary function of the receiver-drier is to separate gas and liquid. The secondary purpose is to remove moisture and filter out dirt. The receiver-drier usually has a sight glass in the top. This sight glass is often used to charge the system. Under normal operating conditions, vapor bubbles should not be visible in the sight glass. The use of the sight glass to charge the system is not recommended in R-134a systems as cloudiness and oil that has separated from the refrigerant can be mistaken for bubbles. This type of mistake can lead to a dangerous overcharged condition. There are variations of receiver-driers and several different


desiccant materials are in use. Some of the moisture removing desiccants found within are not compatible with R-134a. The desiccant type is usually identified on a sticker that is affixed to the receiver-drier. Newer receiver-driers use desiccant type XH-7 and are compatible with both R-12 and R-134a refrigerants. ACCUMULATOR Accumulators are used on systems that accommodate an orifice tube to meter refrigerants into the evaporator. It is connected directly to the evaporator outlet and stores excess liquid refrigerant. Introduction of liquid refrigerant into a compressor can do serious damage. Compressors are designed to compress gas not liquid. The chief role of the accumulator is to isolate the compressor from any damaging liquid refrigerant. Accumulators, like receiver-driers, also remove debris and moisture from a system. It is a good idea to replace the accumulator each time the system is opened up for major repair and anytime moisture and/or debris is of concern. Moisture is enemy number one for your A/C system. Moisture in a system mixes with refrigerant and forms a corrosive acid. When in doubt, it may be to your advantage to change the Accumulator or receiver in your system. While this may be a temporary discomfort for your wallet, it is of long term benefit to your air conditioning system.



今天,当我们驾驶的汽车,很多人,同样可以享受舒适的水平,我们习惯于 在家庭和工作。与推动一个按钮或幻灯片的杠杆,使无缝过渡,从加热到冷却, 再不想这怎么发生变化。 那是, 除非发生差错。 因为出现的汽车空调系统在 1940 年代,许多事情已经发生了广泛的变化。改进,如电脑自动温度控制(允许你设 定所需温度,系统自动调整)和改善整体的耐久性,增加了复杂性,今天的现代 空调系统。不幸的是,该天的“自己动手”的修复这些系统,几乎是过去的事。 增加了并发症,我们现在有严格的环境法规管理非常简单的任务,如充电系 统,俗称氟利昂制冷剂。 (氟利昂是商标名称为制冷剂换热,是制造公司) 。广泛 的科学研究已经证明的破坏性影响这种制冷剂的臭氧层, 及其制造已被禁止在美 国和其他许多国家已加入共同签署的蒙特利尔协议,具有里程碑意义的协议,介 绍了 1980 的限制生产和使用消耗臭氧层的化学品称为。 现在比以往任何时候,你的汽车修理工是在怜悯这个新的环境立法。他不但 必须认证采购制冷剂和修复您的空调,他的店也必须承担的费用,购买昂贵的专 用设备,确保了捕捉这些消耗臭氧的化学品,应打开修复系统。简单的说,如果 你的机械师已花费更多的修复您的车辆-他将收取你更多。基本知识的空调系统 是重要的,因为这将使你做出更明智的决定,在你的修复选项。 应的一个主要问题就是从你的空调, 你可能遇到新的术语。 “改造” “替 像 和 代制冷剂, “现在你力学词汇。你可以得到一个选项“改造” ,而不是仅仅维修和 补给与氟里昂。改造涉及作出必要的修改你的系统,这将使它重新接受, “环保” 这一新的制冷剂的制冷剂,特性。具有较高的操作压力,因此,您的系统,依赖 于年龄,可能需要更大或更强大的零件计数器其固有的高压力的特点。这样,在 某些情况下,将大大增加最终修复费用。如果没有进行适当,可减少冷却效率相 当高的经营成本,降低舒适。

而每三个类型不同,设计的概念和非常相似的一个。最常见的组件,使这些 汽车系统如下:压缩机,冷凝器,蒸发器,孔口管,热力膨胀阀,贮液干燥器, 蓄电池。



于同一目的。此外,你会有一个 receiver-dryer 或蓄电池,但都没有。 上的更多信息,空调,检查汽车空调信息服务器 压缩机通常称为系统的心,压缩机皮带驱动泵是固定在引擎。它负责压缩和传输 制冷剂气体。 该空调系统分为两面,一个高压侧和低压侧;定义为排放和吸。由于压缩机基本 上是一个泵,它必须有一个进水口和一个排气的一边。进气,或吸边,在制冷剂 气体从蒸发器的出口。在某些情况下,它通过蓄电池。 一旦制冷剂吸入吸入侧,它是压缩和发送到冷凝器,它可以传输的热量吸收,从 车辆内部。

1. 冷凝器
这是在该领域的热耗散发生。冷凝器,在许多情况下,将有许多相同的外观作为 散热器在汽车作为两者有非常类似的功能。冷凝器的散热设计。它的位置通常是 在前面的散热器,但在某些情况下,由于空气改善车辆的机构,它的位置可能不 同。凝汽器必须有良好的空气流动的任何系统在运行。在后轮驱动车辆,这通常 是通过利现有的发动机冷却风扇。前轮驱动车辆,冷凝器的空气流动是补充与一 个或多个电动冷却风扇() 。 热压缩气体引入冷凝器顶部,他们冷静下来。当这些气体冷却,凝结和退出冷凝 器底部为高压液体。

2.蒸发器 2.蒸发器
位于车内,蒸发器作为吸热元件。蒸发器提供了多种功能。其主要职责是删除从 车辆内部。第二个好处是除湿。为暖空气经过铝翅片冷却器蒸发器线圈,包含于 空气中的水分凝结在其表面。灰尘和花粉通过坚持其湿表面漏了外面。在潮湿的 日子里,你可以看到这是滴水从你的车。放心,这是很正常的。 理想的蒸发器的温度 320 华氏度或 00 摄氏度。制冷剂进入蒸发器的底部为一个 低压液体。温暖的空气通过蒸发器翅片使制冷剂沸腾(制冷剂具有非常低的沸 点) 。作为制冷剂开始沸腾,它能吸收大量的热量。这是热,然后进行了制冷剂 的车外。其他几个组成部分协同工作的蒸发器。如上所述,理想温度蒸发器线圈 是 320 华氏度的温度和压力调节装置必须是用来控制温度。 虽然有许多不同的设 备,其主要功能是保持相同;在蒸发器压力低,蒸发器冻裂;冷冻蒸发器线圈不 会吸收的热量少。 压力调节装置 控制蒸发器的温度可以通过控制制冷剂的压力和进入蒸发器的流量。许多变化, 压力调节器介绍了 1940 年代以来在下面列出,是最常见的发现。

3.孔管 3.孔管

孔口管,可能是最常用的,可以发现在大多数通用汽车和福特汽车模型。它坐落 在进口管的蒸发器,或在液体,介于冷凝器出口与蒸发器的入口。这一点可以在 一个正常运作的系统的定位面之间的冷凝器出口与蒸发器的入口, 突然改变从热 到冷。你应该看到小酒窝置于线保持孔管的移动。大多数孔口管中使用的测量大 约三英寸长,由一个小铜管,包围的塑料,并覆盖有滤网两端。这是并不罕见, 这些管堵塞小碎片。虽然便宜,通常为三至五美元,劳动代替一个涉及回收制冷 剂,开放系统,更换孔管,疏散和再充电。这一点,它可能是有意义的安装一个 较大的预过滤器前面的孔口管的风险减少到最低限度这一问题再次发生。 福特公 司的一些模型永久贴在孔口管的液体线。这些可以被切断和更换组合过滤器/孔 组装。

另一个常见的制冷剂调节器是热力膨胀阀, 或温度。 常用的进口和售后服务系统。 这种类型的阀门能够感知温度和压力,是非常有效的调节制冷剂流向蒸发器。这 几个变化的阀门是常见的。 另一个例子是一个热力膨胀阀是克莱斯勒的 “块” 型。 这种类型的阀门通常位于防火墙,蒸发器之间的入口和出口管和液体和吸线。这 些类型的阀门,虽然有效,有一些缺点在孔口管系统。像孔口管这些阀门可以成 为堵塞的碎片,但也有小部分可能坚持和故障由于腐蚀。

该接收器上使用的高侧系统使用热力膨胀阀。这种类型的计量阀需要液态制冷 剂。确保阀门得到液态制冷剂,利用接收器。其主要功能的接收器是分离气体和 液体。次要的目的是去除水分和过滤灰尘。该接收器通常有一个玻璃顶。这种玻 璃通常用来充电系统。在正常操作条件下,汽泡不应该是可见的视线玻璃。利用 视镜收费系统是不建议在信息系统作为云量和油分离的制冷剂是可以错误用现 有的气泡。这种类型的错误能导致一个危险的多条件。有变化的 receiver-driers 和几个不同的干燥剂材料的使用。一些水分除去干燥剂内发现 不兼容的信息。干燥剂式通常是确定一个不干胶贴在贮液干燥器。新 receiver-driers 使用干燥剂型 xh-7 和具有相容和 R -制冷剂换热。

是蓄电池系统容纳孔管计制冷剂进入蒸发器。 它是直接连接到蒸发器出口和储存 多余的液体制冷剂。介绍了液态制冷剂进入压缩机可以做严重损害。目的是压缩 气体压缩机的液体。主要作用的蓄能器分离从任何破坏液态制冷剂压缩机。蓄电 池,也喜欢 receiver-driers,除去杂质和水分从系统。这是一个好主意代替蓄 电池系统每次打开了大修,水分和/或碎片的关注。水分的头号敌人,你的空调 系统。水分在一个系统的混合制冷剂和形成腐蚀性酸。怀疑的时候,它可能是你

的优势,改变蓄能器或接收器系统。虽然这可能是一个暂时的不适,你的钱包, 这是长期受益的空调系统。好的人-车-环境系统的设计。


网站首页 | 网站地图 | 学霸百科 | 新词新语
3986 3986.net