Crowd Gates - Design Details
Crowd Gates powered by air motors are the most widely used gates in the industry. Ben Vandenberg and Rolf Reisgies initially designed and developed the gates as a joint engineering project. (1977, Chino, CA). Air operated crowd gates are now manufactured and sold by every major dairy equipment manufacturer - Tech for Ag as well as DeLaval/Germania, Westfalia/Surge, BouMatic, Albers, Norbco and others.
They are popular for good reasons:
- Above all, they are safe. No electricity anywhere near the cows.
- Air controls are inherently reliable, with annual maintenance cost from zero to a couple of hundred dollars at the very most.
- They are of 'heavy duty' design and last any number of decades. Yes, decades.
There are three basic design elements - The Carriage, The Gate and the Controls
The Carriage runs in (2) 4" channels that are either welded to the top of the holding pen fence or are mounted on brackets to the wall of the holding pen. The Carriage:
A drive shaft transmits the power of the gear drive to both sides of the gate. Gate pulls itself forward on two stationary chains inside the 4" channels. Drive installed in the center of the gate, therefore equal torque to both sides.
There is a Master Control Box, typically installed in the parlor and a Remote Control Box installed at the far end of the holding pen. Both boxes have (5) buttons: Forwards, Reverse, Up, Down and Stop.
You can raise and lower the gate anywhere in the holding pen. The basic idea is that while you are milking the tail end of this group, someone else can bring the next group into the holding pen behind the gate. When you are done, raise the gate, return it over the waiting group, lower it behind them and push 'Forward'. Continuous milking at it's best.
The gate itself is suspended from the carriage on two pivot points. Two air cylinders lift the gate to a height of roughly 7 1/2 ft above the holding pen floor. This height can be more or less if need be.
TechForAg Crowd Gate
Click small picture to enlarge
Photos copyright © 2007 Technology for Agriculture * Unauthorized use is prohibited.|
Photos l to r top row:
1. Holding pen cleaned and ready to go shortly before milking.
2. 3 garage doors separate parlor from holding pen - keeps it warm in the winter and flies out in the summer.
3. TechForAg Crowd Gate - 24ft wide - all air driven - no electricity what-so-ever.
4. Drive shaft driven by air motor.
5. Air Motor and 50:1 Gear Drive. Motor runs on any pressure, 75psi recommended; Gate stalls out against cows, follows them as they move forward.
6. Gate installed high enough to clear Skid Loader.
7. Main Control station in back of parlor, near holding pen. There's a remote box at the back of the holding pen.
8. Stainless Crowd Gate Cylinders 4“ bore x 24” stroke; lifts gates up to 28 ft; this gate is 24 ft wide.
9. Stainless cylinder comes with all-stainless hardware, nuts and bolts.
10. Stainless Crowd Gate cylinder in action.
Photos l to r bottom row:
11. 10 ft long V-Lane for Milker from where he would encourage cows to enter parlor by themselves without him entering holding pen.
12. Stainless Holding Pen Fences - 4“ verticals filled with concrete, 2” horizontals.
13. Man-pass half way down holding pen, with swing-away gate.
14. 10“ x 8” concrete Curb strengthens Fence and keeps 'Used Feed' out of Milker's lane.
Air Driven Gate at Marty Mulcahy's new dairy near Dane, WI
- 'Carries' the gate forwards and backwards
- Provides anchor points for the lift cylinders
- Is driven by an Air Motor, running on about 100 psi of air and operating thru a 50:1 gear box.
Copyright 2007 Technology For Agriculture LLC * All Rights Reserved
Technology For Agriculture LLC
1855-A West Davenport St., Rhinelander, WI 54501 | Rolf's Mobil 715-360-3660 * Fax 715-362-7595 |