Lovejoy 68514427836 Variable Speed Pulley 1 Hp B Belt

Product Description

The LOVEJOY 68514427836 is a spring loaded variable speed pulley from the Econoline series, designed for use in belt-driven mechanical power transmission systems. It features a 5.65-inch maximum diameter, a 2.69-inch minimum pitch diameter, and an overall length of 4.13 inches. The pulley accepts a 1-1/8-inch bore with a 1/4 x 1/8-inch keyway for positive shaft engagement. Rated at 1 horsepower at 1750 RPM and 3/4 horsepower at 1150 RPM, this variable speed pulley is installed by millwrights, HVAC technicians, and industrial maintenance professionals working on variable-speed fan and blower applications.

This pulley is suited for residential and light commercial HVAC systems, industrial blowers, and fan drives where variable airflow control is required. The spring-loaded design allows the effective pitch diameter to shift automatically in response to load and speed changes, enabling stepless speed variation without manual adjustment. It is compatible with B-series V-belts and is typically used in systems where motor speed remains fixed but driven equipment speed must vary within a defined range.

Key Features

• Spring-loaded variable pitch design enables automatic, stepless speed adjustment
• Rated at 1 HP at 1750 RPM and 3/4 HP at 1150 RPM
• Maximum outside diameter of 5.65 inches with a 6-inch nominal outside diameter
• Minimum pitch diameter of 2.69 inches
• 1-1/8-inch bore with 1/4 x 1/8-inch keyway for secure shaft mounting
• Econoline series construction sized for B-belt trade size applications

Compatibility

Designed for use with B-series V-belts. Suited as an OEM-style replacement or aftermarket variable speed pulley in belt-driven HVAC fan, blower, and light industrial drive applications requiring a 1-1/8-inch bore and B-belt fitment.

Installation Notes

Installation should be performed by a qualified millwright or HVAC technician. Disconnect and lock out all power to the drive system before handling the pulley or belt. Verify shaft diameter and keyway dimensions match the pulley bore before installation, and ensure the drive belt is properly tensioned and aligned per the equipment manufacturer specifications. Sheave and pulley alignment tools are recommended to minimize bearing load and belt wear.