电动线性执行器的类型介绍及选型指南（连载一）

什么是电动线性推杆？它们与其他类型的推杆有何不同？它们有哪些优缺点？

这里将详细介绍，了解到从最常见的电动推杆类型及其基本操作到其众多应用和控制方法的内容。

What are electric linear actuators? How do they differ from other types of actuators? What are their advantages and disadvantages?

Here, we’ll cover the details you need to know. You’ll learn everything from the most common types of electric actuators and their essential operation to their numerous applications and control methods.

什么是电动线性执行器？

What is an Electric Linear Actuator?

线性执行器是一种传递力和运动的装置，沿着单个驱动轴方向推或拉。相比之下，旋转执行器传递扭矩和圆周运动，绕其驱动轴顺时针或逆时针旋转。

最常见的线性执行器包括气动、液压和电动执行器。气动线性执行器是最简单、最便宜的选择，但它们需要压缩空气，而压缩空气并非总是可用。液压执行器通常比气动执行器更可靠，但复杂度更高，成本也更高。电动执行器是最灵活的选择，可提供平稳、精确且免维护的运动。

电动线性执行器是一种将电能转换为机械功的机电装置。内置电动机的旋转运动通过内置齿轮箱、丝杠和驱动螺母转换为直线运动。电动机的扭矩输出通过齿轮箱放大，从而驱动丝杠。导螺杆的旋转运动又使驱动螺母沿延伸轴平移。最终，随着导螺杆顺时针或逆时针旋转，连接在驱动螺母上的活塞会伸出或缩回。

A linear actuator is a device that delivers force and motion, pushing or pulling along a single drive axis dimension. In contrast, a rotary actuator delivers torque and circular motion, twisting clockwise or counterclockwise around its drive axis.

The most common linear actuators include pneumatic, hydraulic, and electric actuators. Pneumatically linear actuators are the simplest and cheapest option, but they require compressed air, which may not always be available. Hydraulic actuators are generally more reliable than pneumatics but are significantly more complex and costly. Electric actuators are the most flexible option offering smooth and precise maintenance-free motion.

An electric linear actuator is an electro-mechanical device that converts electrical energy into mechanical work. The rotary motion of an internal electric motor converts to linear motion through an internal gearbox, lead screw and drive nut. The torque output from the motor is amplified through the gearbox to drive a lead screw. The rotational motion of the lead screw, in turn, translates the drive nut along the axis of extension. Finally, a piston attached to the drive nut is either extended or retracted as the lead screw rotates clockwise or counterclockwise.

电动线性执行器的类型

Types of Electric Linear Actuators

电动线性执行器有多种标准尺寸和配置，适用于从最小的机器人夹持器到大型工业和农业机械的各种项目。

Electric linear actuators come in several standard sizes and configurations suitable for projects ranging from the smallest robotic grippers to large industrial and agricultural machinery.

常见的线性执行器尺寸

Common Linear Actuator Sizes

微型线性执行器

Micro Linear Actuators

图 1：微型线性执行器

Figure 1: Micro linear actuators

微型线性执行器体积小巧、功耗低且价格实惠。它们最适合尺寸受限且无需施加较大推力的应用。大多数微型线性执行器的行程长度通常小于 200 毫米，甚至可能短至 10 毫米。微型线性执行器制造商通常提供 100 毫米（4 英寸）的行程长度。微型线性执行器的最大推力因型号而异，预计在 50 N（11 lbf）至 100 N（22 lbf）之间。因此，微型线性执行器所需的功率更低。驱动电压为 6、12 或 24 V 直流电，最大负载下的功耗通常低于 12 瓦。图 1 展示了微型线性执行器的示例。

Micro Linear Actuators, are small, low-power, affordable linear actuators. They are best employed when size is the major constraint, and large forces are unnecessary. The stroke length of most micro linear actuators is usually less than 200 mm and may be as short as 10 mm. 100 mm (4 inches) is a typical length offered by micro linear actuator manufacturers. The maximum force delivered by micro linear actuators varies across models. Expect values from 50 N (11 lbf) to 100N (22 lbf). As a result, micro linear actuators require less power to operate. Drive voltages will be either 6, 12, or 24 volts DC, and the power consumed at the maximum load will typically be under 12 watts. Figure 1 shows an example of an micro-linear actuator.

中型线性执行器

Mid-Sized Linear Actuators

图 2：中型线性执行器

Figure 2: Mid-Sized linear actuators

中型线性执行器是最常见的电动线性执行器类型。它们比微型线性执行器更大，最适合需要更大推力且尺寸并非至关重要的情况。中型线性执行器的行程长度差异很大，从最短1或2英寸到最长60英寸不等。图2展示了中型电动线性执行器的示例。

制造商通常根据中型执行器的最大动态推力（而非行程长度）来分类。虽然大多数微型线性执行器的推力最高约为100N（或22 lbf），但中型线性执行器的动态推力通常为数百磅力 (lbf)，有些甚至高达4448 N（1000 lbf）。为了支持更大的推力，中型线性执行器采用12伏或24伏驱动电压，功耗可能高达120瓦。

Mid-Sized linear actuators are the most common variety of electric linear actuators. They’re larger than micro linear actuators and are best suited when greater forces are required, and size is not of the utmost importance. The stroke lengths for mid-sized linear actuators vary greatly from as little as 1 or 2 inches to as great as 60 inches. Figure 2 shows an example of a Mid-Sized linear actuators.

Instead of stroke length, manufacturers tend to categorize mid-sized actuators by their maximum dynamic force. While most micro linear actuators top around 100N (or 22 lbf), mid-sized linear actuators commonly offer dynamic forces in the hundreds of pound-force (lbf), with some delivering up to 4448 N (1000 lbf). In support of their more significant power, mid-sized linear actuators are driven at either 12 or 24 volts and may draw up to 120 watts.

重型线性执行器

Heavy-Duty Linear Actuators

图 3：重型线性执行

Figure 3: Heavy-Duty linear actuators

重型线性执行器是工业电动线性执行器中尺寸最大、功率最强的型号之一。重型线性执行器的行程长度与中型执行器相似，大多数型号的行程长度在1到60英寸之间。大多数重型线性执行器可提供数千磅力的动态力。虽然大多数常见型号提供的力在1,000到15,000磅力之间，但也有一些极其强大的重型电动线性执行器，其动态力高达100,000磅力。

重型电动线性执行器结构坚固，包括更耐用的丝杠、变速箱和强大的电机。一些功率最大的型号没有集成电机，需要开发人员选择并安装专用电机。图3展示了重型线性执行的一款额定力为1,200磅力的重型线性执行器。

Heavy-Duty linear actuators are some of the largest and most powerful industrial electric linear actuators. The stroke lengths available for heavy-duty linear actuators are similar to mid-sized actuators, with most models offering between 1 and 60 inches of extension. Most heavy-duty linear actuators deliver dynamic forces in the thousands of pound-force. While most common models provide between 1,000 and 15,000 lbf of force, it is possible to find extremely powerful heavy-duty electric linear actuators delivering up to 100,000 lbf of dynamic force.

Heavy-duty electric linear actuators offer robust construction, including more rugged lead screws, gearboxes, and powerful electric motors. Some of the most powerful models are manufactured without an integrated electric motor and require the developer to select and install a design-specific motor. Figure 3 shows a heavy-duty linear actuator for 1,200 lbs of force.

常见的线性执行器配置

Common Linear Actuator Configurations

大多数电动线性执行器都属于四种易于识别的机械结构之一。

Most electric linear actuators fall into one of four easily recognizable mechanical architectures.

直角或垂直执行器

Right Angle or Perpendicular Actuators

直角执行器将电动机置于执行器活塞的侧面，电机轴垂直于活塞。制造商通常使用蜗轮将电动机的输出扭矩旋转90度，以驱动活塞丝杠。图2展示了直角配置线性执行器。

由于蜗轮螺旋螺纹的复杂性，蜗轮传动比的选择比简单的直齿正齿轮传动要少。因此，直角电动线性执行器可能无法提供多种速度与扭矩的组合。一些制造商可能会通过在蜗轮传动和丝杠之间添加一个正齿轮来克服这一限制。

直角执行器的蜗轮传动具有两个关键优势。首先，采用蜗轮传动的电动线性执行器产生的噪音往往比同类正齿轮平行执行器更小。其次，许多蜗轮传动结构具有自锁功能，因为它们的内摩擦系数大于蜗杆导程角的正切值。这种自锁特性赋予它们出色的静态负载能力，即线性执行器抵抗施加到执行器活塞上的外力的能力。

Right angle actuators place the electric motor to the side of the actuator piston with the motor shaft oriented perpendicular to the piston. Manufacturers most commonly utilize worm gears to translate the output torque of the electric motor 90 degrees to drive the piston lead screw. Figure 2 shows a right-angle configured linear actuator.

Due to the complexity of their spiral threads, worm gearing is available in fewer gear ratios than simpler straight-toothed spur gearing. Thus, right-angle electric linear actuators may not be available in many speed versus torque combinations. Some manufacturers may overcome this limitation by placing an additional spur gear between the worm gearing and the lead screw.

The worm gearing of right-angle actuators offers two key advantages. First, electric linear actuators with worm gear tend to generate less noise than comparable spur gear parallel actuators. Second, many worm gear configurations are self-locking as their internal coefficient of friction is greater than the tangent of the worm’s lead angle. This self-locking property gives them excellent static load capacity, which is the ability of the linear actuator to oppose external forces applied to the actuator piston.

直列式执行器

Inline Actuators

图4：微型笔式直列执行器

Figure 4: Micro Pen Inline Actuators

直列式电动线性执行器将电机直接置于执行器活塞后方，并与活塞成一线。因此，直列式执行器外形纤细，通常类似于液压管，电机隐藏在外管内。电动直列式执行器专为需要窄型执行器以避免机械干扰的应用而设计。虽然它们比同等的垂直或平行执行器更长，但没有其他配置能像它一样纤细。图 4 展示了Mirco Pen直列式执行器。

大多数电动直列式执行器使用行星齿轮系将扭矩从电机驱动轴传递到活塞丝杠。行星齿轮系比平行和垂直线性执行器中使用的平行正齿轮和蜗轮更复杂。正齿轮和蜗轮系通过单齿轮接触点传递扭矩。相比之下，行星齿轮系通过每个行星齿轮和中心太阳齿轮之间的多个接触点传递力。因此，行星齿轮系可以承受更高的扭矩，同时减少磨损。然而，齿轮啮合数量的增加往往会产生更大的噪音。

Inline electric linear actuators place the motor directly behind and in line with the actuator piston. As a result, inline actuators offer a slim profile, often resembling a hydraulic tube with the motor concealed within the outer tube. Electric inline actuators are designed specifically for applications requiring a narrow actuator to avoid mechanical interference. While they are longer than equivalent perpendicular or parallel actuators, no other configuration is as slim. Figure 4 shows Mirco Pen Inline Actuators.

Most electric inline actuators use planetary gear trains to transfer torque from the motor drive shaft to the piston lead screw. Planetary gear trains are more complex than the parallel spur gears and worm gears used in parallel and perpendicular linear actuators. Spur and worm gear trains transfer torque through single-gear contact points. In contrast, planetary gear trains transfer force through multiple contact points between each planet gear and the central sun gear. Thus, planetary gear trains can handle higher torque with reduced wear. However, the increased number of gear interfaces tends to generate more noise.

平行驱动执行器

Parallel Drive Actuator

平行驱动执行器将电机平行放置在执行器活塞的侧面。这种放置方式较为普遍，可以平衡执行器的整体宽度和长度。与直列式设计相比，将电机放置在活塞的侧面可以缩短整体长度；与直角驱动相比，将电机平行放置在活塞上可以缩短整体宽度。因此，平行驱动执行器适用于空间长度和宽度有限的应用。图 1 和图 3 均为平行驱动执行器的示例。

大多数平行驱动执行器利用内部正齿轮将扭矩从电机传递到活塞丝杠。这种简单的传动装置使制造商能够提供具有更大齿轮比范围的型号，从而提供更广泛的速度和动态扭矩选择。

Parallel drive actuators place the electric motor parallel and to the side of the actuator piston. This orientation is prevalent and balances the overall width and length of the actuator. Placing the motor to the side of the piston reduces overall length compared to an inline design, and orienting the motor parallel to the piston reduces overall width compared to a right-angle drive. Thus, parallel drive actuators are suitable for applications where the overall length and width of the space are limited. Figures 1 and 3 are both examples of parallel drive actuators.

Most parallel drive actuators utilize internal spur gears to transfer torque from the electric motor to the piston lead screw. This simple gearing allows manufacturers to offer models with a greater range of gear ratios which translates to a broader selection of speed vs. dynamic torque.

电动线性执行器的最佳应用

Best Applications of Electric Linear Actuators

电动线性推杆广泛应用于从家庭自动化到农业和工业机械的各种应用。它们几乎适用于所有需要推拉负载的应用，例如升降结构、滑动材料或旋转接头或阀门。电动线性推杆节能高效，维护成本低，并且相对于其他类型的线性推杆而言，总拥有成本较低。

以下部分将通过介绍各种实际应用来描述电动线性推杆的广泛用途。

Electric linear actuators are useful in applications from home automation to agricultural and industrial machinery. They apply to almost any application that requires pushing or pulling a load. Examples include raising or lowering a structure, sliding material, or rotating a joint or valve. Electric linear actuators are energy efficient, require little maintenance, and have a low total cost of ownership relative to other types of linear actuators.

The following sections describe the broad utility of electric linear actuators by presenting various real-world applications.

物料搬运和包装

Material Handling and Packaging

图 5：自动化包装设备

Figure 5: Automated Packaging Equipment

线性推杆是精准、可靠且可编程运动的卓越动力源，适用于产品包装等物料搬运活动。工业包装流程需要推杆之间紧密同步，以便快速可靠地对产品进行分类并将其放入最终纸箱中。

线性推杆尤其适用于自动化包装阶段的动态多品种环境。借助合适的传感器和控制系统，采用电动线性推杆的包装系统可以维护大量独特的包装操作库，并执行快速切换。因此，循环时间得以缩短，机器效率得以提升。

工厂越来越多地将电动线性推杆用于传统上依赖气动和液压解决方案的包装步骤。用于码垛产品的自动化物料搬运系统的一个典型示例是能够轻松地将箱子堆放在托盘上而无需人工干预的系统。

Linear actuators are excellent sources of precise, reliable, and programmable motion applicable to material handling activities such as product packaging. Industrial packaging processes require close synchronization between actuators to sort and place products quickly and reliably into their final carton.

Linear actuators are especially well suited to an automated packaging stage’s dynamic high mix environment. With appropriate sensors and control systems, packaging systems utilizing electric linear actuators can maintain large libraries of unique packaging operations and execute rapid changeover. Thus, cycle times are improved, and machine efficiency increases.

Factories increasingly use electric linear actuators for packaging steps that traditionally rely on pneumatic and hydraulic solutions. An excellent example of an automated material handling system for palletizing products would be one that could easily stack boxes onto pallets without human intervention.

食品和饮料制造

Food and Beverage Manufacturing

图 6：自动化肉类成型设备

Figure 6: Automated Meat Molding Equipment

电动线性推杆对于当今高产量的食品和饮料生产环境至关重要。除了精度和可靠性之外，电动线性推杆还非常清洁，非常适合严格的食品和饮料处理要求。具有适当 IP 防护等级的推杆型号具有耐腐蚀性，并且能够承受极高的压力，甚至浸泡清洁条件。

例如，电动线性推杆可用于自动切碎和切割，其灵活性使其能够快速调整切片尺寸和力度。线性推杆也非常适合食品的排列和分类。它们可以定位穿过传送带系统的产品，以便根据产品属性进行分类或排列以进入下一操作阶段。

Electric linear actuators are vital to today’s high-volume food and beverage manufacturing environment. In addition to their precision and reliability, electric linear actuators are also clean, making them well-suited to the stringent food and beverage handling requirements. Actuator models with the appropriate IP rating resist corrosion and can regularly endure extremely high pressure or even immersion cleaning conditions.

Electric linear actuators can be found, for instance, in automated chopping and cutting, where their flexibility enables rapid variation in slice size and force. Linear actuators are also well suited to food alignment and sorting. They can position products traversing a conveyor system to sort by product property or align for the next stage of operation.

农业机械

Agricultural Machinery

图 7：现代拖拉机装配

Figure 7: Modern Tractor Assembly

坚固耐用的电动线性推杆已取代部分重型农业机械的液压运动解决方案。液压推杆虽然动力强劲，但体积庞大、重量沉重，且缺乏某些农业环境所需的精度和清洁度。此外，与食品饮料行业一样，具有适当 IP 防护等级的电动线性推杆能够可靠地抵御恶劣天气以及农用化学品和清洁剂的危害。

例如，电动线性推杆可用于喷雾器，用于调节喷杆和喷嘴，从而精确覆盖作物。制造商也在拖拉机驾驶室内外使用电动线性推杆，用于远程调节难以触及的通风设备、后视镜和车窗。农业饲料系统是电动线性推杆的另一个重要应用。农民可以使用线性推杆自动控制饲料投放的时间和投放量，确保牲畜正确、持续地获得饲料。

Rugged electric linear actuators have replaced some hydraulics motion solutions for heavy agricultural machinery. While hydraulic actuators are powerful, they are large, heavy, and lack the precision and cleanliness required for some agricultural environments. Further, as with the food and beverage industry, electric linear actuators with the appropriate IP rating can reliably withstand exposure to the elements and the hazards of agricultural chemicals and cleaning agents.

Electric linear actuators can be found, for example, on sprayers, where they can adjust booms and aim nozzles for accurate crop coverage. Manufacturers also use them in and around the tractor cabin, where actuators can remotely adjust out-of-reach ventilation, mirrors, and windows. Agricultural feed systems are another great application of electric linear actuators. Farmers can use linear actuators to automate the timing and volume of feed mechanisms and ensure animals receive feed correctly and consistently.

家庭和办公室自动化

Home and Office Automation

图 8：百叶窗的家庭自动化

Figure 8: Home Automation of Blinds

电动线性推杆是实现家庭和办公室环境自动化运动的卓越且经济高效的解决方案。例如，通风系统设计师可以使用线性推杆调节内部风门，自动调节建筑管道内的气流，将气流引导至特定区域，或通过混合气流来调节空气。

窗户和窗帘是典型的自动化应用。遥控线性推杆可以打开或关闭触手可及的窗户。各种窗帘也可以使用电动线性推杆进行调节。中央控制系统可以自动定位百叶窗、窗帘或遮光帘等遮盖物，以便按照每日自动计划同步移动多个窗户。

在家庭自动化行业，线性推杆非常适合移动家居内部结构，例如厨房橱柜、家电、壁橱和大电视。尤其是平板电视收纳系统，在家庭中越来越受欢迎，因为电视机可以垂直升起或旋转到天花板上，以便在不使用时将其隐藏起来。

Electric linear actuators are an excellent and cost-effective solution to automate motion within home and office environments. Designers of ventilation systems, for example, may use linear actuators to adjust internal dampers and automate the regulation of airflow through building ductwork, direct airflow to specific zones, or condition air by mixing air flows.

Windows and window treatments are typical automation applications. Remote-controlled linear actuators can open or close windows out of reach. A variety of window treatments can also be adjusted using electric linear actuators. A central control system can automate the positioning of coverings such as shutters, curtains, or blinds to move several windows in unison on an automatic daily schedule.

In the home automation industry, linear actuators are well suited to moving internal home structures such as kitchen cabinetry, appliances, closet organization, and large televisions. Flat-panel TV storage systems, in particular, have become a popular item in homes where the television is either raised vertically or pivoted into the ceiling to remove it from view when not in use.

汽车和船舶应用

Automotive and Marine Applications

电动线性推杆是汽车和船舶行业的标准配置。它们在原始设备制造商和售后市场中也越来越普遍。其多功能性使其可用于打开、关闭、调整角度或提升通风口、引擎盖、后备箱、车门、隔间和面板。搭配合适的控制器，它们可以针对不同的运动速度或中间位置执行复杂的运动轨迹。添加力控制功能可提供一定程度的安全性，例如，当检测到冲击或阻力时，如果有物体挡住门，可以阻止门关闭。

电动线性推杆在船舶行业同样有用，在这种情况下，设计师依靠具有适当 IP 等级的型号来保护它们免受潮湿、盐分或喷雾的影响。船主使用电动线性推杆来打开或关闭不易接近的舱口、通风口或窗户。

Electric linear actuators are standard across both the automotive and marine industries. They are increasingly commonplace for the original equipment manufacturers and the aftermarket industry. Their versatility makes them useful for opening, closing, angling, or lifting vents, hoods, trunks, doors, compartments, and panels. Paired with suitable controllers, they can operate complex motion profiles for different movement speeds or intermediate positions. Adding in force control provides a measure of safety where detecting an impact or resistance could, for instance, stop a door from closing if something is in the way.

Electric Linear actuators are similarly helpful in the marine industry, in which case designers rely on models with a suitable IP rating to protect them from humidity, salt, or spray. Boat owners use electric linear actuators to open or close hatches, vents, or windows that are not easily accessible.

机器人技术

Robotics

最后，电动线性执行器在机器人构造中堪称天作之合。其精准度以及力和位置反馈选项使其成为肌肉的完美模拟。驱动机器人关节（旋转关节和移动关节）的电动线性执行器可提供精确的关节位置、速度和加速度控制。

线性执行器与功能强大的控制器配合使用时，可以有效地执行自由空间运动轨迹和受约束的力反馈运动。它们可以操作各种机器人关节，包括关节臂的肘部、精密夹持器和其他工具、XY 定位器以及转向组件。协同控制系统可以同步多个线性执行器的通道，以驱动多关节运动序列。

Lastly, electric linear actuators are a natural fit in robotics construction. Their precision and options for both force and position feedback make them an excellent approximation of a muscle. Electric linear actuators driving robotic joints (revolute and prismatic) offer precise joint position, velocity, and acceleration control.

Linear actuators can effectively execute free space motion trajectories and constrained force feedback motions when paired with a capable controller. They can operate a variety of robotic joints, including the elbows of articulating arms, precision grippers and other tooling, XY positioners, and steering assemblies. Cooperative control systems can synchronize multiple channels of linear actuators to drive multi-joint motion sequences.