As the valve opens by the cam rod, the diapharam is pulled up creating a partial vaccume inside the dash pot. When the valve is released by Corliss's patented catch and release mechanism the vaccume in the dash pot pulls the diaphram down, which is connected to the valve, rapidly closing the valve. The reason for the valves closing so rapidly is because steam will expand in the cylinder and there is no need to fill the cylinder with steam 100% of the stroke
@metal15051 Thank you for that explination. Do you know if Mr. Corliss built any engines before he invented that system? Or is my memory or the museums dates wrong. In the demo I do recall they showed how the govenor would interupt the valves but that is all I remember. I know they run this at 1 pm on weekends if you would like to see it.
@inwoodcutter Well i know Corliss was working with engines for obviously a while. You see what Corliss wanted to do was make more efficient use of steam, which resulted in the Corliss valve gear. You are correct about the governor manipulating the valves instead of the steam line. As i mentioned the valve gear has a the ever so important catch and release mechanism, now when the governor begins to kick in what it will do is cause the catch and release mechanism to drop the valves earlier.-----
As you can see on the engine the valves are solidly connected to the cam rod and move "constantly" with the cam. If the engine had a Corliss valve gear the intake valves would be separated from the cam, about half way through the stroke by the patented catch and release mechanism. After the intake valves have been separated from the cam they are closed rapidly by the use of dash pots. The dash pots are simply just a pot with a sealed diaphram and a small bleed valve on the bottom side -------
@metal15051 Please explain further. The museum displays this engine as being built by Corliss in his facility. I believe the date on this machine is somewhere around 1846. The patent granted to Corliss for his valve gear was not issued until 1849. So if the museum has their dates right this could have been made before he invented the valve gear. Corliss is the maker not the style.
by dropping the valves earlier less steam is let into the cylinder slowing the engine
metal15051 1 year ago
As the valve opens by the cam rod, the diapharam is pulled up creating a partial vaccume inside the dash pot. When the valve is released by Corliss's patented catch and release mechanism the vaccume in the dash pot pulls the diaphram down, which is connected to the valve, rapidly closing the valve. The reason for the valves closing so rapidly is because steam will expand in the cylinder and there is no need to fill the cylinder with steam 100% of the stroke
metal15051 1 year ago
@metal15051 Thank you for that explination. Do you know if Mr. Corliss built any engines before he invented that system? Or is my memory or the museums dates wrong. In the demo I do recall they showed how the govenor would interupt the valves but that is all I remember. I know they run this at 1 pm on weekends if you would like to see it.
inwoodcutter 1 year ago
@inwoodcutter Well i know Corliss was working with engines for obviously a while. You see what Corliss wanted to do was make more efficient use of steam, which resulted in the Corliss valve gear. You are correct about the governor manipulating the valves instead of the steam line. As i mentioned the valve gear has a the ever so important catch and release mechanism, now when the governor begins to kick in what it will do is cause the catch and release mechanism to drop the valves earlier.-----
metal15051 1 year ago
As you can see on the engine the valves are solidly connected to the cam rod and move "constantly" with the cam. If the engine had a Corliss valve gear the intake valves would be separated from the cam, about half way through the stroke by the patented catch and release mechanism. After the intake valves have been separated from the cam they are closed rapidly by the use of dash pots. The dash pots are simply just a pot with a sealed diaphram and a small bleed valve on the bottom side -------
metal15051 1 year ago
Sorry, this engine is not a Corliss engine, it does not have the Corliss Valve gear, This is simply a rotary valve engine
metal15051 1 year ago
@metal15051 Please explain further. The museum displays this engine as being built by Corliss in his facility. I believe the date on this machine is somewhere around 1846. The patent granted to Corliss for his valve gear was not issued until 1849. So if the museum has their dates right this could have been made before he invented the valve gear. Corliss is the maker not the style.
inwoodcutter 1 year ago