John Wilson
Mechanical
Hi guys -
Looking for a few ideas here from fellow members on a patented invention we have. In a nutshell it is a way for a pocket of fluid to be able to pass through a piston, to be recycled at the front end of the cylinder to return the piston to its starting position. When we started on this it was for pneumatics and in particular pneumatic nail guns. We have working prototypes where the body of the gun is 30% smaller than your average off the shelf pneumatic gun and has 25% more power.
The way conventional nail guns work is that towards the front of the cylinder they have exhaust ports. As the piston is travelling forward, the air in front of the piston is exhausted through these ports to a reservoir that surrounds the cylinder within the body. This reservoir takes up about 30% of the body chamber and is contained especially for the piston to be able to return. So, as the piston reaches the front and has fired the nail the compression within this reservoir then returns the piston to its starting position. This is what makes nail guns quite big and bulky. In saying this though, the body also must contain some reservoir air to fire the shot. The disadvantage of this is not only the extra bulk but as the piston closes in on the nail, it starts losing power through the compression.
Our invention has exhaust ports right out the front, so air in front of the piston is going straight to atmosphere. We have a bump stop at the front of the cylinder with ports through it for the purpose of letting pressure air through. When the piston closes in to the front at the same time as firing the nail, the piston compresses the bump stop sealing off the front exhaust ports. We have a small fluted area on the wall of the front of the cylinder. The purpose of this is that we have a series of small bores through the piston from the rear to one of two grooves that have o-rings. The rear groove and o-ring acts as a seal as normal between piston to cylinder, while the front groove o-ring is sealing the air from the rear while the piston is on its driving stroke. When the piston compresses the bump stop, the front groove is within the fluted area and the pressure (generally 100psi) from the air behind the o-ring then raises the o-ring slightly out of the groove and a small pocket of pressure air is then transferred from the rear of the piston to this small front pocket in front of the piston in the area of the bump stop. For a brief moment, both the front and the rear of the piston have similar air pressure of say 100psi. However the next action is the trigger opens an exhaust port at the rear of the gun (nothing to do with our patent - all guns act this way), therefore, there is now rapidly decreasing pressure at the rear of the piston while the front still has say 100psi. The front o-ring now naturally closes, while the rear o-ring prevents air from escaping over the top of the piston. The piston now returns like a mortar to its starting position.
Because we don't have a reservoir chamber that must act on compression like a conventional gun, we have proven we have at least an extra 25% more nail driving power, and as we don't need the reservoir in the body we can reduce the body size by up to 30%, which is the standard reservoir size in a conventional gun.
But although we've proven this idea with nail guns - (we still have engineers working on some current prototypes) I'm hoping that some members might have had experience with other types of equipment that might benefit from our patent. We put hydraulic in the patent on the advice of our attorneys without having any knowledge whether or not this could be beneficial for any hydraulic systems as we have no experience with hydraulics. Others along the way have said that perhaps it could benefit paint ball guns, but once again I have never even seen one. Another said that it may improve one way actuators, making them at least smaller and lighter. If this is so this could benefit say aircraft pneumatics, reducing the weight on an aircraft.
Anyone, I'd be very happy to listen to any ideas on this any member has.
(By the way, the illustration shows three o-rings - this was an early drawing until we realised two would suffice). Our website has a couple of short videos showing a prototype in action against a Paslode gun. Cheers
John
Looking for a few ideas here from fellow members on a patented invention we have. In a nutshell it is a way for a pocket of fluid to be able to pass through a piston, to be recycled at the front end of the cylinder to return the piston to its starting position. When we started on this it was for pneumatics and in particular pneumatic nail guns. We have working prototypes where the body of the gun is 30% smaller than your average off the shelf pneumatic gun and has 25% more power.
The way conventional nail guns work is that towards the front of the cylinder they have exhaust ports. As the piston is travelling forward, the air in front of the piston is exhausted through these ports to a reservoir that surrounds the cylinder within the body. This reservoir takes up about 30% of the body chamber and is contained especially for the piston to be able to return. So, as the piston reaches the front and has fired the nail the compression within this reservoir then returns the piston to its starting position. This is what makes nail guns quite big and bulky. In saying this though, the body also must contain some reservoir air to fire the shot. The disadvantage of this is not only the extra bulk but as the piston closes in on the nail, it starts losing power through the compression.
Our invention has exhaust ports right out the front, so air in front of the piston is going straight to atmosphere. We have a bump stop at the front of the cylinder with ports through it for the purpose of letting pressure air through. When the piston closes in to the front at the same time as firing the nail, the piston compresses the bump stop sealing off the front exhaust ports. We have a small fluted area on the wall of the front of the cylinder. The purpose of this is that we have a series of small bores through the piston from the rear to one of two grooves that have o-rings. The rear groove and o-ring acts as a seal as normal between piston to cylinder, while the front groove o-ring is sealing the air from the rear while the piston is on its driving stroke. When the piston compresses the bump stop, the front groove is within the fluted area and the pressure (generally 100psi) from the air behind the o-ring then raises the o-ring slightly out of the groove and a small pocket of pressure air is then transferred from the rear of the piston to this small front pocket in front of the piston in the area of the bump stop. For a brief moment, both the front and the rear of the piston have similar air pressure of say 100psi. However the next action is the trigger opens an exhaust port at the rear of the gun (nothing to do with our patent - all guns act this way), therefore, there is now rapidly decreasing pressure at the rear of the piston while the front still has say 100psi. The front o-ring now naturally closes, while the rear o-ring prevents air from escaping over the top of the piston. The piston now returns like a mortar to its starting position.
Because we don't have a reservoir chamber that must act on compression like a conventional gun, we have proven we have at least an extra 25% more nail driving power, and as we don't need the reservoir in the body we can reduce the body size by up to 30%, which is the standard reservoir size in a conventional gun.
But although we've proven this idea with nail guns - (we still have engineers working on some current prototypes) I'm hoping that some members might have had experience with other types of equipment that might benefit from our patent. We put hydraulic in the patent on the advice of our attorneys without having any knowledge whether or not this could be beneficial for any hydraulic systems as we have no experience with hydraulics. Others along the way have said that perhaps it could benefit paint ball guns, but once again I have never even seen one. Another said that it may improve one way actuators, making them at least smaller and lighter. If this is so this could benefit say aircraft pneumatics, reducing the weight on an aircraft.
Anyone, I'd be very happy to listen to any ideas on this any member has.
(By the way, the illustration shows three o-rings - this was an early drawing until we realised two would suffice). Our website has a couple of short videos showing a prototype in action against a Paslode gun. Cheers
John
