View Larger Image I’m stumped. 30 Comments ⬇ I don’t get stumped very often. What can you tell me about this mysterious contraption? How does it work? Thank you to Kerry Heminger of Commercial Door Metal Systems for the photos! You need to login or register to bookmark/favorite this content. By Lori Greene|2018-08-31T11:37:02-04:00July 31st, 2018|Door Closers|30 Comments Share This Story, Choose Your Platform! FacebookTwitterLinkedInRedditWhatsappGoogle+TumblrPinterestEmail About the Author: Lori Greene Recent Posts 30 Comments David Moyer July 31, 2018 at 3:12 am - Reply Lori, This is an early model Closer/Holder. The device is air-powered, held open with air pressure applied to the air diaphragm. You could manually pull it out of hold open as long as the air pressure didn’t exceed 30 psi. The Reading Door Closer Company was purchased by DORMA in the late 1980s (?) and has recently become part of dormakaba. This device was discontinued in the early 90s, perhaps earlier. I only ever saw drawings for this in the “discontinued’ engineering archives. David Bob Caron July 31, 2018 at 6:08 am - Reply A pneumatically controlled hold-open? Cda July 31, 2018 at 7:06 am - Reply Interesting I wonder what the other side looks like ? It does say door holder, so it must have some type of release. Colins Jacob August 12, 2018 at 2:46 am - Reply I assume there’s a braking shoe or something that gets actuated cause of the Pneumatics by linkages. Tom O'Connor July 31, 2018 at 2:11 pm - Reply https://patents.google.com/patent/US4222147 This invention relates to hydraulic door closer apparatus, and more particularly, to hydraulic door closer apparatus having “assist” or “operating” features to facilitate opening of a door. It is the principal object of this invention, however, to provide apparatus in which closing of a door is achieved through the operation of what is essentially a conventional door closer, balanced, or, if desired, over-balanced by a pneumatic actuator associated with it. It is another object of this invention to provide a mechanically simple door closer, energy efficient in its operation, and relatively easy to install with a minimum of skilled labor, and in particular, requiring no electrical controls. TM July 31, 2018 at 3:04 pm - Reply This is a UL Listed Dohickeythingamabob introduced in the mid 80’s. Pat Jones July 31, 2018 at 3:07 pm - Reply Pneumatic hold-open to drop door in fire (similar to pneumatic smoke damper?) Just a guess. Pat Jones July 31, 2018 at 3:08 pm - Reply Pneumatic door holder to drop the door the door on fire alarm (similar to pneumatic smoke damper?) Just a guess Anthony Wan July 31, 2018 at 3:10 pm - Reply Lori, It looks like a pneumatic hold open. Hints are the PSI threshold label and the air line connector on top of the closer body. Probably used for rated doors that would need hold opens in a high hazard (flammable materials) situation. When fire alarm is triggered, pressure is released from the pneumatic hold open contraption. Joel Niemi July 31, 2018 at 3:14 pm - Reply pneumatic-assisted operator? Thus the 10-30 psi range on the sticker? Chuck Park July 31, 2018 at 3:15 pm - Reply I’ve seen some strange and/or old hardware, but never anything like this! It appears to be some type of pneumatic or hydraulically controlled smoke check. alex sency July 31, 2018 at 3:16 pm - Reply it is a pneumatic door holder. they usually have a pneumatic relay to release with fire alarm. it must be quite old. Tony Calistro July 31, 2018 at 3:23 pm - Reply Could be some sort of fusible link do-hicky??? Darren Patton July 31, 2018 at 3:23 pm - Reply its a Pneumatic door equalizer Rich July 31, 2018 at 3:31 pm - Reply Wonderful photos. My guess is a pneumatic door hold open device. The white elbow in the second picture looks to be a pressure line. The small chamber with the rod in the center would be a diaphragm to hold the arm in place when energized. The small label lists the pressure required to operate the hold open function. The top photo shows something held down with a screw that looks like a wire connector. It could also be a fusible link for fire release. I would like to see more photos with a true explanation of the hold open. I would guess friction with a small roughed up surface or knurling to hold a clutch ring. Bill Cushman July 31, 2018 at 3:31 pm - Reply Looks like a bowden cable or hydraulic plunger – controlled brake, rigged to stop or slow down the rotation of the closer. Curtis Meskus July 31, 2018 at 3:39 pm - Reply looks like a pneumatic door open device, I had some specked on a job and told the to put electric operators on each of the doors so if the compressor or tubing failed all of the doors would not fail a the same time. Eric July 31, 2018 at 3:44 pm - Reply I’m guessing the plastic elbow is pneumatic and connected to a tube through the wall to a central air compressor. I’m willing to buy a round of drinks that this is either an elaborate retrofit to convert a mechanical closer to an operator or a predecessor to the LCN 4800 series pneumatic operators. D LoBello July 31, 2018 at 3:47 pm - Reply Don’t know, looks like it could be a pneumatically operated hold open judging by the plastic “plumbing” fitting. Frank Ehrman July 31, 2018 at 4:18 pm - Reply Looks like maybe a MACGyvered LCN Pneumatic Operator ….just my guiess. Dave Snell, AHC July 31, 2018 at 4:20 pm - Reply Looks like Dormas’ attempt at a Pneumatic closing device. Robert Chillino July 31, 2018 at 4:32 pm - Reply Lori, I would say that is an air assisted auto operator. Possibly an aftermarket product? Robert Infinite Doors Keith Krienke July 31, 2018 at 4:47 pm - Reply Looks like a closer with a Pneumatic hold open device on it. Edward K. Takahashi July 31, 2018 at 5:14 pm - Reply It looks like the first kind of closer with a top-mounted automatic pressure sensitive device, probably reacting to pressure build up as the fire gets going, that closes the door. Jerry Austin July 31, 2018 at 5:23 pm - Reply The label says it was manufactured by Reading Door Closer Corporation. Reading was purchased by Dorma Glas, a member of the Dorma Group. From what I can find Dorma Glas manufacured heavy decorative doors. Reading and later Dorma patented several door closer that used pnematic assist. I think https://patents.Google.com.patent/us4222157 Door Closer with Assist or Door Operating Features looks close to the pictured closer This patent was originally issued in 1978 if it is indeed the same device. I think the idea was to reduce wear found in hydraulic only devices and was aimed at a hospital market. I ran across an interesting site: http://www.nedoorcloser.com/mfg_desc.html David Moyer July 31, 2018 at 6:44 pm - Reply Lori – I submitted a comment on this device early this morning. Evidently it didn’t send. This device is a late 80s / early 90s door holder made by Reading Door Closer Co. Reading was a private company, purchased by DORMA in the 80s. An air compressor supplies pressurized air @ 10-30 psi to the diaphragm atop the closer. Cutting the air supply allows the door to close automatically or one can pull it out of hold open. I only ever saw drawings of it in the engineering drawing archives. It was discontinued before I arrived there as engineering manager in the mid 90s. Nice piece of history – does it still function? Dave Peter Schifferli July 31, 2018 at 7:18 pm - Reply I’m *guessing* someone rigged this closer to allow pneumatic operation of the door, either opening and/or enhanced closing power. Unlikely to have been a factory supplied option. Tom Chin July 31, 2018 at 8:46 pm - Reply Looks like a light duty pneumatic operator (LCN)? Darrell B July 31, 2018 at 10:06 pm - Reply It looks like it might be a fusible link. Bryan July 31, 2018 at 10:24 pm - Reply Pneumatic building controls from days passed. Held open with 10~30 psi air pressure and hopefully tied to the fire alarm system. Leave A Comment Cancel replyComment Save my name, email, and website in this browser for the next time I comment. Don't subscribe All Replies to my comments Notify me of followup comments via e-mail. You can also subscribe without commenting.