Clutch torque limiter

Types of Clutch Torque Limiters

A clutch torque limiter is mainly designed to slip when excess torque is transmitted by the motor. Following the working principle, manufacturers have outlined various types of torque limiters. The types are mostly based on the working mechanism and design, as illustrated below.

• Mechanical Torque Limiter

  It is a traditional torque limiter design that uses a mechanical decoupling method to slip. When excess torque is transmitted, the limiter slips and uncouples to protect the equipment from damages and overloads. Most mechanical torque limiters have adjustable slipping points. Therefore, they can be tuned and adjusted to engage or disengage at certain torque levels.

• Friction Torque Limiter

  This is a specific kind of mechanical torque limiter. It employs friction as the main decoupling force. The design involves a friction element and a rotating shaft. When excess torque is transmitted, the friction elements engage with a rotating shaft. This action creates enough heat to uncouple the driving and driven components, thus providing protection.

• Fusing Torque Limiter

  It features a design that offers protection against overloads by melting a fuse element. The fuse components are usually made of metal alloys with low melting points. Under normal operating conditions, the fuse element conducts current. However, when excess torque is transmitted, excess heat is generated, which may cause the component to melt. This action breaks the circuit, thus providing protection.

• Slip Clutch Torque Limiter

  It is a certain kind of mechanical torque limiter that uses a slip mechanism to provide protection. When excess torque is transmitted, the clutch components slip, allowing controlled relative motion between the driving and driven components.

• Shear Pin Torque Limiter

  This limiter features a design that uses shear pins to offer protection against overloads and excessive torques. The shear pins are placed in a loading path to transmit torque between two components. They are normally designed to withstand certain torque limits. Therefore, when excessive torque and overloads are experienced, the pins shear off, preventing further injury.

• Overload Torque Limiter

  It's a device that limits and prevents transmission of excessive torque to machinery components. As a result, it helps to protect the equipment from damages and failures.

• Elastic Element Torque Limiter

  This element features an elastic mechanism including but not limited to belts, springs and rubber elements. When an excessive torque level is reached, the elastic components deflect or slip, thereby absorbing the excess torque. This motion protects the machinery components from damages.

Specification and maintenance of clutch torque limiter

Specification

• Rated Torque:

  The torque at which the clutch will start to slip (beneficial for protecting overloads and safeguarding machinery). It can be altered to suit applications by modifying spring tension.

• Bypass:

  If it is essential for the clutch to function but not in the dedicated torque range, a bypass can be used to put it in the circuit.

• Operating Temperature:

  It is the temperature a functioning clutch can withstand. This highlights the importance of selecting the correct clutch to protect machinery investment from damage.

• Operating Environment:

  Some clutch torque limiters are made for wet, sandy, or corrosive places. Others are designed to work well underwater. Knowing where a tensioner will be used is essential for selecting the proper environment by incorporating materials and coatings.

• Backing Flange:

  Used to mount on solid surfaces with a standard fitting. This ensures proper functioning and alignment during installation.

• Disc Materials:

  The combination of disc and plate materials can influence torque, clutch function, slip, wear, and operating temperature.

• Backlash and Play:

  This has a significant effect on wear. Backlash is the distance between a driving directional gear tooth and the gear tooth it drives in a clutch. Play is the slack or free movement in a clutch's axial or radial direction. They affect clutch adjustment and operation.

Maintenance

Understanding what a torque limiter clutch does is crucial to knowing how to maintain it properly. A clutch like this one protects motors, gearboxes, and drive solutions by allowing certain torques to slip. When installing or maintaining this kind of clutch, it is vital to know the suitable torque. Knowing how and when the clutch will slip needs to be known to avoid damaging the machinery.

Generally, the maintenance of these clutches should include regular electrical inspections because this is usually how they work. If their functioning is to be ensured, their bypass should not be used, and any electrical or mechanical issues should be addressed immediately.

Another thing to consider in maintenance is the environment where the clutch will be. If water, dirt, or dust gets into the machine, it will have to be cleaned, and the clutch will need to be maintained. The correct materials and coatings should be used to withstand the environmental conditions.

In maintenance, all bolted and secured places should be checked to ensure nothing is loose or come undone. This should be done periodically and aligned with the operational practices and policies of the industry where the clutch is being used.

Application Scenarios of Clutch Torque Limiters

Clutch torque limiters are useful in many industrial areas, including manufacturing, transportation, and food service. Here are some common application scenarios.

• Protecting conveyor belts

  Clutch torque limiters are commonly used on conveyors found in factories, warehouses, and distribution centers. It acts as a protective device to avoid having the conveyor overloading, thereby helping to extend the service lifespan of the equipment. Using a clutch torque limiter on the conveyor belt also prevents unexpected equipment failure from occurring and reduces maintenance needs.

• Packaging machinery

  In a packaging machine харе, the torque clutch limiter can be used to protect the equipment from being damaged due to the uneven force. The torque limiter will disconnect the power source of the machine automatically if the torque exceeds the set value. This action effectively safeguards the corrected packages, thereby helping to prevent products from being harmed or ruining the packages.

• Printing presses

  For printing press machines, incorporating a clutch torque limiter can help ensure the print products’ quality and reliability. If there is too much torque acting on the machine, the limiter will disengage the power source. By doing this, the machine will be protected from sustaining any form of damage, thereby extending its service lifespan. This method also shields the print product from any flaws.

• Wind power generation

  In the domain of renewable energy development, wind energy has become one of the mainstream power sources. A wind turbine's gearbox assists in boosting the turbine's rotation speed to generate electrical energy. This essential component may be at risk due to excessive torque caused by turbulence or equipment failure. Therefore, having a clutch torque limiter assists in safeguarding the gearbox by disconnecting the power transmission path whenever the exerted torque exceeds the predetermined limit.

• Food machinery

  Food processing machines, such as mixers, grinders, and conveyors, also use clutch torque limiters. This device protects the machine from injuries caused by overloading or too much torque. Using a clutch limiter in food processing machines helps ensure the machines work well and maintain food safety standards.

How to Choose Clutch Torque Limiters

Generally, the following factors are to be considered when selecting a clutch torque limiter for a specific application:

• Load Protection:

  Determine the type of machinery by conducting a thorough risk analysis. Consider its operational characteristics, the intended purpose of using a torque limiter, and the range of possible overload situations. Select a torque limiter that provides the desired level of protection against mechanical damage caused by excessive loads.

• Slip Torque Selection:

  Establish the slip torque required for the specific application by taking into consideration factors such as operating conditions, the physical characteristics of the machines, and the coupling's design. Choose a torque limiter with a calibrated slip torque that aligns with these factors to ensure proper functioning and protection.

• Actuation Method:

  Decide on the actuation method for the torque limiter, whether it is manual, automatic, or remote, based on the operational requirements of the application. Consider factors such as the need for maintenance, convenience, and safety. Select the appropriate actuation method to ensure reliable operation and protection.

• Temperature Range and IP Rating:

  Choose a torque limiter that can withstand the environmental conditions of the installation site. Select a limiter with an appropriate temperature range and IP (Ingress Protection) rating to ensure its reliability and performance in harsh environments.

• Cost-Effectiveness:

  Finally, cost-effectiveness must be considered by balancing performance, protection level, and operating requirements. Select a clutch torque limiter that provides good cost-effectiveness and satisfies the application's needs while considering the budget constraints.

Clutch torque limiter Q&A

Q1: What is the working principle of a torque limiter clutch?

A1: Torque limiters are mechanical devices that disconnect when an adjustable torque is exceeded. They are protective devices that are designed to protect driven and driving components. Normally, they're engaged. When the set torque is reached, the torque limiter will slip and disconnect.

Q2: What is the difference between a torque limiter and a clutch?

A2: A clutch is intended to engage and disengage the drive under normal operating conditions, while a torque limiter is intended to slip when the pre-set torque is reached to prevent overload and potential damage. Torque limiters can operate in slip mode, while clutches generally cannot.

Q3: How does one adjust a torque limiter clutch?

A3: The adjustment of torque limiters is typically done by changing the spring tension by using a spanner or torque wrench. Other methods may include adjusting the nut or using a set of lock screws.

Q4: What are some applications of clutch torque limiters?

A4: Clutch torque limiters are used in applications such as conveyors, compressors, fans, pumps, machine tools, and mixers, among other industries that include aerospace, automotive, electric, and electronics.