|History of the Brockwood Stall Shi*fter
You might wonder why we call it the Hybrid Woody so here is its history.
One of my earliest model original motorized Stall Shi*fters underwent a 2-year evaluation for John Lyons at his ranch in Parachute, CO. A very favorable article published in the December 1999 issue of Lyons' Perfect Horse Magazine summarizes the results of the test. It reads:
After about 5 years my wife convinced me I should build a model that was easier for the ladies to move around the barn so I made some modifications and built her what we called the Little Shifter.
It was a complete change in body style and drive mechanism. We changed to an all steel, laser cut and baked on powder coated enamel finish. The motor we selected was the only one available on the market that would run at nearly the right speed, a Leeson 340 rpm right angle gear motor. I shortened the sifting tray by 12 inches. The slower motor speed and shortened screen tray reduced throughput but it was still quite satisfactory.
Some customers who had the old style wooden machine bought the new Little Shifter and observed that the new design had a lower throughput than the original 48" screen with belt drive so I made some design changes and added a 48" screen option with a variable speed motor.
The angle of the sifting screen was adjusted by lowering the output screen roller. We duplicated the efficiency of the original wooden model using a different method of applying an angle to the screen and even though it worked very well the screen was being driven in a plane at a slightly obtuse angle to the crankshaft and this caused the tie rod ends to wear prematurely which introduced play in the drive train.
Over the years we learned that the weakest link was the gear drive motor, more specifically, the coupling between the Drive motor and the right angle gearbox. When normal tie rod end wear allowed play in the drive train the shock was transmitted back through the gearbox to the coupling splines and they in turn would develop a hairline crack and the shaft would spin inside the coupling and the machine would not work. This was easily repaired with an inexpensive part but it was a weak point in the design of the motor.
This problem we learned could be expected to occur in all motors over a period of time depending on usage, care and speed of operation. The 340 rpm gear motor exhibited very little failure because it was used in smaller barns averaging about 8 stalls per day. We could expect years of reliable operation with no problem for the Little Shi*fter standard model.
I discontinued building the variable speed model in late 2009 because the difference between the 340 rpm fixed speed and the maximum rpm of the variable speed motor was not cost effective. A 17% increase in speed resulted in about a 2% increase in time saved and the additional wear on the drive trains more than doubled the spline failure rate. It was my judgment that this was not cost effective for the customer so I went back to the original belt and pulley drive mechanism set at a fixed speed of ~ 400 rpm, the optimum speed. I have incorporated all the strong points of both machine types, the original Woody and Little Shi*fter. I eliminated the expensive DC gear motor and variable speed controller both being sources of machine failure.
When tie rod ends wear normally the drive train gets a little looser and louder in operation but there is no longer has a weak link between the motor and the drive because there is a belt that absorbs the shock introduced by a slight amount of play in the rod end. The motor is a lower cost motor but a higher horsepower; the gear motors were 1/4 hp and 1/6th hp. The newer fixed speed motor is a 1/3 hp or 1/4 hp. The cost of building the crankshaft drive assembly makes the cost of the motor and drive assembly together almost exactly the cost of the single unit gear motor which had to be replaced as a whole unit for about $600 in the event of a motor or gearbox failure.
design allows replacement of only the discrete
components on the rare occasion one fails. This would be a motor, belt, flange
bearing or crank, all of which are non proprietary and can be replaced
local purchase. The whole idea of the hybrid machine is to increase
reliability, lower maintenance cost and maintain the optimum sifting
capability. I still offer the 15 day free trial and the three year
Deluxe Hybrid Woody
Deluxe Hybrid Woody
day free trial
1997 to 2011
John Lyons steel strut
standard Little Shi*fter
Variable Speed Deluxe
Variable Speed chopped
Retro hybrid proto type
Standard Hybrid Woody
Deluxe Hybrid Woody
Questions or Comments? Please e-mail email@example.com
© 1997 - 2013 | All Rights Reserved - Brockwood Farm | Website designed by David Martin Design
Deluxe Worm Shi*fter