MADE IN THE USA
Oldham Shaft Couplings Complete Assemblies starting at $23.75 with quantity discounts available
Basic Oldham Shaft Couplings Design
Inherent in the Oldham design is a unique characteristic-uniform velocity, regardless of shaft misalignment. In their original form, Oldham type couplings had backlash, needed lubrication, and accepted little angular misalignment. Renbrandt is the originator of improvements which greatly enhance their performance.
The Nylon centerpiece virtually eliminates backlash, noise, and the need for lubrication. The cylindrical cross pins permit greater angular misalignment (up to 5º).
Features
- Uniform Velocity
- Greater Misalignment (5º)
- No Radial Load
- Easy Separation
- Zero Backlash
- Light Weight/Low Inertia
- Moderate Torque
- 6000 Volt Insulation
- Small Size
- Torsional Rigidity
- Low Cost
Materials and Finishes
- Hubs – – Brass, nickel plated.
- Centerpieces Nylon (Others such as Polycarbonate on request)
- Set Screws – Stainless Steel, cup point, hex socket (STD) or slotted available. Orientation of set-screws with respect to crosspins maintaned.
Set Screw Sizes:
- Up to .125 Bore -Two 4-40 @120°.
- to .3125 Bore -Two 6-32 @ 90°.
- to .375 Bore -Two 4-40@ 90°
Size 1 $23.75 each Quantity Discounts Available
| Current Product No. | Bore Diameters +0.002 -0.000 |
|---|---|
| M201-33 | 0.125 X 0.125 |
| M201-00 | 0.938 X 0.938 |
| M201-03 | 0.938 X 0.125 |
| M201-22 | 0.120 X 0.125 |
| M201-23 | 0.120 X 0.125 |
| M201-02 | 0.120 X 0.938 |
Size 2 $25.25 each. Quantity Discounts Available
| Current Product No. | Bore Diameters +0.002 -0.000 |
|---|---|
| T301-22 | 0.120 X 0.120 |
| T301-23 | 0.120 X 0.125 |
| T301-24 | 0.120 X 0.1875 |
| T301-25 | 0.120 X 0.250 |
| T301-26 | 0.120 X 0.3125 |
| T301-27 | 0.120 X 0.375 |
| T301-33 | 0.125 X 0.125 |
| T301-34 | 0.125 X 0.1875 |
| T301-35 | 0.125 X 0.250 |
| T301-36 | 0.125 X 0.3125 |
| T301-37 | 0.125 X 0.375 |
| T301-44 | 0.1875 X 0.1875 |
| T301-45 | 0.1875 X 0.250 |
| T301-46 | 0.1875 X 0.3125 |
| T301-47 | 0.1875 X 0.375 |
| T301-55 | 0.250 X 0.250 |
| T301-56 | 0.250 X 0.3125 |
| T301-57 | 0.250 X 0.375 |
| T301-66 | 0.3125 X 0.3125 |
| T301-67 | 0.3125 X 0.375 |
| T301-77 | 0.375 X 0.375 |
Size 3 $27.00 each. Quantity Discounts Available
| Current Product No. | Bore Diameters +0.002 -0.000 |
|---|---|
| M501-66 | 0.3125 X 0.3125 |
| M501-67 | 0.3125 X 0.375 |
| M501-77 | 0.375 X 0.375 |
| M501-78 | 0.375 X 0.4375 |
| M501-88 | 0.4375 X 0.4375 |
Set Screw Style
| Size | Dia. | Max. Bore | Length | Weight (oz) | Misalignment Angle | Misalignment Offset | Max Torque | Max RPM | Max Temp. |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1/4″ | .125″ | 7/16″ | 0.055 | 3 | 1/32″ | 20″ oz. | 2500 | 175° F |
| 2 | 1/2″ | .375″ | 21/32″ | 0.25 | 5 | 1/16″ | 80″ oz. | 2500 | 175° F |
| 3 | 5/8″ | .4375″ | 31/32″ | 0.70 | 5 | 1/16″ | 100″ oz. | 2500 | 175° F |
What Are Oldham Shaft Couplings
Oldham shaft couplings are a type of mechanical coupling used to transmit torque between two non-aligned shafts. These couplings can accommodate lateral and angular misalignments between the shafts without generating high stress or reducing the efficiency of the transmission. They are composed of three main parts:
- Two Hubs: These are the parts of the coupling that connect directly to the shafts. Typically, each hub is attached to a shaft, and these hubs are made to fit the shafts precisely, usually through a keyed connection or a set screw.
- Center Disc: This is the intermediary part that sits between the two hubs. It is usually made of a material that is slightly softer than the hubs, often a high-strength plastic like acetal, nylon, or polycarbonate. This disc has grooves that match up with tongues on the inner faces of the hubs, allowing it to slide laterally in relation to the hubs. This sliding action is what allows the coupling to compensate for lateral misalignment between the shafts.
- Torque Transmission: The torque is transmitted from one hub to the other via the center disc. The interlocking design of the disc and hub tongues and grooves ensures that the rotational motion of one shaft is transferred to the other shaft. The design allows for the absorption and compensation of misalignments in parallel (offset shafts) and, to a lesser degree, angular misalignments.
Oldham couplings are known for their simplicity and effectiveness in applications where misalignment is present. They offer several benefits, including:
- Easy Installation and Maintenance: Their simple design allows for easy assembly and disassembly without the need for special tools.
- Misalignment Compensation: They can effectively handle both parallel and angular misalignments without inducing excessive loads and stresses on the shafts and bearings.
- No Backlash: Due to the tight fit between the discs and hubs, Oldham couplings can operate with minimal to no backlash, making them suitable for precise motion control applications.
However, they are not well-suited for applications with significant axial misalignment and are generally not recommended for high-torque or high-speed applications due to the limitations of the materials used for the center disc. Their performance and lifespan can be affected by wear and tear on the center disc, especially under high loads or in harsh environments.
Why Specify Oldham Shaft Couplings?
Specifying Oldham couplings in mechanical designs is beneficial for several reasons, particularly in applications where certain operational conditions and requirements must be met. Here are key reasons to choose Oldham couplings:
- Accommodation of Misalignment: One of the primary reasons for specifying Oldham couplings is their ability to accommodate significant parallel and angular misalignments between two shafts without imposing high stresses on the shafts or bearings. This feature is especially useful in applications where precision alignment is difficult to achieve or maintain.
- Low Backlash: Oldham couplings are designed to minimize backlash, making them suitable for applications requiring high precision and repeatability, such as in automated machinery, precision instruments, and control systems.
- Ease of Assembly and Maintenance: The simple three-piece design of Oldham couplings allows for easy assembly and disassembly. This facilitates maintenance and replacement without the need for realigning the connected machinery or disassembling other components.
- Versatility: With the center disc typically made from a polymer, Oldham couplings can be customized for different torque capacities, damping characteristics, and environmental resistances. The choice of center disc material can be tailored to suit specific application requirements, including temperature tolerance, chemical resistance, and electrical insulation.
- No Lubrication Required: The material properties of the center disc usually eliminate the need for lubrication, reducing maintenance requirements and the potential for contamination in clean environments, such as food processing or semiconductor manufacturing.
- Torsional Rigidity with Flexibility for Misalignment: While Oldham couplings are torsionally rigid, transmitting torque efficiently without significant power loss, they still provide the necessary flexibility to accommodate misalignment, combining the best of both worlds for many applications.
- Cost-Effectiveness: Compared to other types of couplings that offer similar levels of misalignment compensation and torsional rigidity, Oldham couplings are often more cost-effective, providing a good balance between performance and price.
- Vibration Reduction: The center disc can also serve to dampen vibrations and absorb shock loads, protecting sensitive components in the drive system from damage and reducing noise levels in operation.
When specifying an Oldham coupling, it’s essential to consider the specific application requirements, including torque capacity, shaft sizes, misalignment tolerances, environmental conditions, and operational speeds. Proper selection ensures that the coupling will perform effectively, with a long service life and minimal maintenance.