Single blow device

[Robin D]

In an other thred the 1902 Massey patent were mentioned. I

[Frosty]

Unless I misread it, with the valve position control handle that inverts the check valve in the control valve inverted, depressing the treadle causes the tup to decend. How far, how fast and how hard depends on how far you depress the treadle. Releasing the treadle causes the tup to idle in the up position.

Frosty

[Judson Yaggy]

Frosty- Insofar as I can follow you and the language of the patent, I think you are right. But I'm still thinking it thru. I suppose there could be a secondary mechanical system that moves the valve upon depressing the treadle from holding open to stroke and then back to hold open. Perhaps some linkage triggered by the passage of the tup.

Robin- What lines on page 2 are you referring to?

[Robin D]

I

[Judson Yaggy]

Ah, page 5. Yes, you are right. It does seem to be activated by an external linkage, looks like you have to pull a hand lever to engage or disengage this feature? Or does the spring disengage? If we deviate from the patent and use motion of a reciprocating part to activate it still seems to me that it would have better response if it were tup activated (if you could find a way to get it out of the work area for the reasons you stated).

Edited May 5, 2009 by judson yaggy

[Frosty]

The lever changes the direction the foot treadle moves the control valve.

With the lever in the normal forging position the check valve will keep the bottom of the tup ram pressurized when the treadle is released. Tup raised at idle.

With the lever in the clamp position the linkage moves the control valve the other direction so the top of the Tup cylinder is pressurized when the treadle is depressed preventing the Tup from cycling. It comes down and stays down. Clamp or dead blow. The harder you stomp the treadle the harder it hits and clamps.

Release the treadle and the Tup idles in the raised position.

It isn't a sensor of any type reading where the Tup is.

Cycling in this type device is strictly master, slave. The compressor piston is the master and the Tup is the slave. When activated the slave follows the motion of the master. Think of it as a pneumatic see saw.

Isn't going through these old patents fun? I especially like the late 19th century British legalese myself.

Frosty

[Madmike]

So a dead blow is just a rapid treadle depress/release -> clamp/unclamp and clamp cannot hold if the treadle is released...

[Robin D]

Once more, we are talking of the device described in fig 20.
In the text it says that the way to make a single blow is to go quickly from holding up mode (fig17) to working mode (fig 16) and back again, and to do this within a working cycle.
The device -as I understand it- helps you to press the lever at the right time, so to speak. And when the right time is, is censored by the adjustable screw no21 ( fig 20) who reads the position of the pumping piston. Since it is as you say Frosty “a strictly master-slave system” I would argue that in a way a sensor is reading where the tup is, even if its isn't read from the tup itself.
On my Anyang I think it would be easier to read the timing on the flywheel since the pumping piston isn't easily available.
What I was interested in was if any one had used the arrangement and if it was well working. Without having used it I feel that there might be reason to also include a way to stop after a full cycle, but maybe that isn't necessary.
Robin

[Frosty]

A dead blow means the tup comes down and stays there. It's the same thing as clamping but generally to clamp you lower the tup more slowly so as not to actually hit the work.

I'll need to print the thing out again, it's been quite a while since I read it and I can't speak to specific drawings and pieces of text accurately from memory. To this point I have been speaking from my understanding after spending quite a bit of time reading and marking up drawings and text so I wouldn't be surprised if I have things wrong.

I'll rejoin the discussion when I can speak more factually.

Frosty

[nonjic]

First I would define 'proper' single blow as being the type of single blow you get on a steam hammer, any velocity, from any ram position dead blow.

(Not a quick tap on the pedel gives a tap of the ram)

It is my understanding that you cannot get this mode of operation from a 'self contained' hammer without an air resovior. The later model massey 'Clear Space' hammers have an internal resovior at about 45 psi.

I do not believe the earlier hammers did (such as mentioned in the patents). Ive never seen a Massey 'self contained' hammer (old, or very old!) that has any positional sensing equipment on it.

Not all patented ideas were put into production, then or now.

It wouldnt be easy to put a dedicated single blow onto a hammer that is not designed for one (like the small anyangs). I could do it via an external resovoir (charged from pump piston) and external valving / piping to the top and bottom of the ram bore but it would take quite a bit of working out.


On a side note,......

Ive been having a bit of a dig round in the company archives and have found a nice design for a Massey 15kg self contained hammer from 1903 (looks a bit like the one in the patents), that im having a good look at. If I can find somone to make them competitivly (ie in line with the current Chinese / Turkish hammer prices) there might be a new choice on the market in a couple of years ! :D

[Robin D]

The selfcontained will of course continue to be a selfcontain whatever valving I put to it, I don't expect it to become a steamhammer.

I think its possible to make the hammer do single blows, but maybe it isn't worth the trouble.

Thou I