WPT has been producing mechanical PTOs for over 20 years now. Starting with the automotive style flat-faced clutch that is so popular in the irrigation and chipper market, we eventually entered into the over-center market that spans an array of industrial, agricultural, and marine applications. From the beginning, our over-center designs offered both bronze and ball bearing style engagement collars. Each design lent itself to various applications.
In Third Place, Bronze Collars
In the past, the bronze collar design served as the industry standard. Covering both in-line and side-load applications, its simplicity and efficiency made it a fan favorite. However, the bronze collar design had its limitations. For instance, special care had to be taken when it came to maintenance. Lack of grease has always been the bronze collar’s biggest nemesis. Because the collar rides on the shaft with nothing but a thin layer of grease separating it from shaft, failure to maintain this lubrication would result in increased friction. The friction would lead to heat, and before you know it, the collar would seize on the shaft, causing a catastrophic failure.
Another shortcoming of the bronze collar design was engagement handle orientation. Because the collar floats freely on the shaft, the orientation of the engagement handle must be maintained so as not to exert undue pressure on the shaft. Recommended handle orientation for mechanical PTOs using bronze engagement collars is 12 o’clock. When the handle is in this position, it exerts no pressure on the shaft, allowing the collar to float freely and wear evenly. However, not all applications are capable of this handle orientation, severely limiting the use of the bronze engagement collar.
Taking the Silver, Ball Bearing Collars
Like most inventions, the bronze collar was destined to be improved upon. Enter the Ball Bearing Engagement Collar. The ball bearing collar was developed to overcome the shortcomings of the bronze collar. The original design consisted of a bearing encased in a housing that rides on the PTO shaft. This bearing was fed on either side by grease hoses that extended to and through the outer bell housing of the PTO. When properly maintained, the bearing collar was much more forgiving when pressured by the engagement handle, allowing the handle to be oriented in positions that created a wider range of application opportunities. Other benefits include added stability for side loading and collar longevity.
The Gold Standard, Sealed-for-life Collars
WPT has taken the ball bearing engagement collar a step further. Where end-users have always been shackled to the grease gun to ensure proper maintenance, operation, and longevity of their PTOs, WPT has rolled out the first sealed-for-life ball bearing engagement collars in their full line of Pilotless™ mechanical PTOs. By eliminating the old-style bearings, not only has the need to grease your collar gone away but so has the need for internal grease hoses and zerks. Because the sealed bearing system has worked so well for the Pilotless™ line, we have incorporated it into our SP line of mechanicals and eliminated bronze engagement collar assemblies altogether. These developments have created opportunities and capabilities throughout our mechanical PTO line, equating to increased performance and longevity for the end-user.
After years of stagnation in the mechanical PTO world, WPT came and made long overdue design improvements. With the advent of the Pilotless™ design attributes, those improvements have been incorporated into our older designs and breathed new life into older, tried, and true models.
If you are an OEM and utilize mechanical PTOs in your packages, give WPT an opportunity to work with you today. Our staff of talented engineers is eager to assist you in designing the most efficient, cost-effective solutions for your company. You can email us at email@example.com or give us a call at (940) 761-1971.
Written by: John Bardwell, North American Sales Representative