US1126574A - Automatic door-lock for fire-doors. - Google Patents

Description

H. SCHERER. AUTOMATIC DOOR LOOK FOR FIRE DOORS.

APPLICATION FILED JAN. 30, 1914.

Patented Ja11.26, 1915.

HE Nwmm PETERS C0. PHOTO LITHQ, HIAbH KINITED STATES PATENT I-IEhTRY SCI-IERER, OF BILLINGS, MONTANA.

AUTOMATIC DOOR-LOCK FOR FIRE-DOORS.

Application filed January 30, 1914.

To all whom it may concern:

Be it known that I, HENRY SOHERER, a citizen of the United States, residing at Billings, in the county of Yellowstone and State of Montana, have invented new and useful Improvements in Automatic Door- Locks for Fire-Doors, of which the following is a specification.

This invention relates to improvements in door latches and especially to latches for use on furnace doors and stoves.

One feature of my invention consists in the novel means employed to hold a door or gate in a specified position, either opened or closed.

Another feature is the use of novel means to hold the fire door of a stove or furnace in its closed position, but not absolutely locked against force applied from within the furnace.

Another feature of the invention consists in the shape of the receiving cam and the positive means employed for holding the .cam in its receiving position.

Heretofore trouble has been experienced in the operation of furnaces not only from the weight of the doors to be lifted in opening or closing the furnace but because no adequate device has been provided for allowing the door to be opened or closed with but slight effort on the part of the operator. where explosions have occurred within furnaces and the door has been locked shut, as is the case where the ordinary furnace door is lifted up and over an incline and its latch drops into a recess against the door frame. To open such a door a vertical motion is necessary before the door may be swung open horizontally. Hence one of the objects of my invention is to provide a door latch which may be operated equally well from either side of the door and thereby avoid the danger of confined explosions and the resulting damage.

The invention consists in the novel construction of parts illustrated in the accompanying drawings and described and claimed in the following specification and claims.

In the drawings-Figure 1 is a face view of a furnace door illustrating the latch parts in engagement. Fig. 2 is a side view of the same door showing the door resting against the front of the furnace in its latched position, and illustrating in dotted Specification of Letters Patent.

This has been especially true- Patented Jan. 26, 1915.

Serial No. 815,445.

lines the position of the latch parts when the door is opened. Fig. 3 is a face View, enlarged, of the receiving block. Fig. 4 is a side view of the same block shown in Fig. 8.

1 represents the front of a furnace with a door frame 2 and door 3 mounted on suitable hinges 4-. Attached to the door but spaced therefrom to prevent heating is a handle 5. Fastened to the front of the furnace and adjacent the door frame 2 is a bracket 6, and pivotally attached to this bracket 6 by means of a bolt 7 is a cam receiving block 8. It will be observed that the lower part of the block 8 is divided into the forks 9 and fitted astride of the bracket 6. The upper portion of the cam block 8 is re cessed at 10 and the lower portion between the forks is shouldered at 11. Rigidly mounted on the door 3 and extending horizontally therefrom so as to swing over the bracket 6 is a keeper bar 12 arranged to enter the recess 10 of the cam block 8.

Block 8 is always in a position to engage with and receive the bar 12 and needs no attention from the operator. When the door is opened the shoulder 11 of the cam block 8 rests on the forward portion of the bracket 6, (Fig. 2) and the recess 10 is in the same horizontal plane as the bar 12. In the operation of the device, the door is given a closing movement, the bar 12 engages the recess 10 and block 8 and rides up and over the pivot point of the block, lifting the door with it and finally bringing the door to rest against the furnace front. At this point the weight of the door keeps it shut. As the bar 12 is carried by the block 8 there is a frictional movement between the two parts, the block 8 having a rotary movement relative to the bar 12. Any explosion from within need exert only sufficient force to push the weight of the door past the pivot point of the block 8 to open the same. When the door is pulled open past the pivot point the bar 12 leaves the recess 10 and the block 8 rests on the bracket 6 as previously described.

From the foregoing it will be seen that my invention provides a latch which needs no attention to keep it in order, and further that it is always in operable position and but little efiort is necessary, the momentum of the door on closing being sufficient to carry it over the pivot point of the cam re ceiving block. In my door latch a simple horizontal pull on the door is suiiicient to open it. It will be noticed that the weight of the door on the cam block is suflicient to hold the door in a latched position under ordinary circumstances as against the open ing action of falling coal within a furnace or if used in gate construction of wind against a gate; further that it readily yields to a force sufficient to overcome its weight against the cam and door frame. The horizontal force required to open the door may be gaged by the distance between the furnace front and the pivot point of the block 8 on the bracket 6, it being obvious in the manu-, facture of the door latch that as this point is moved from the door frame the block will more nearly assume a horizontal position and the resultant propping action against the doorwill be more evident. It will be further observed that all parts used in the invention are strong and heavily con strueted, thus eliminating any danger of breakage or war-ping due to heat or other misuse.

Particular attention is called to the fact that while I have illustrated the latch as ap-. plied to a furnace door the construction is equally well applicable for use in any type of door, gate or window, whether swinging orsliding. Any desired changes may be made in the size and proportion of the part without departing from the scope of my invention.

Having described my invention, what I,

her to swing in the general direction of the movement of the door and engage said extension to, lift the. door up and over the pivot and down into closed position, the door bearing inwardly and downwardly against the door frame.

2. The combination with a door and a door frame constituting two members, of an extension on one member, and a receiving block provided with a notch pivotally mounted on the other member to swing in the general direction of the movement of the door and engage said extension with said notch to lift the door up and over the pivot point and down into the closed position, said. receiving block rotating with respect to said extension, there being a frictional engagement between the surface of the notch in the receiving block and the projection during this movement.

8. The combination. with a door and. a door frame constituting two members of an extension on one member and a receiving block provided with a notch pivotally mounted 011 the other member to swing in the general direction of the movement ofthe door, and engage said extension with said notch to lift the door up and over the pivot point and down into the closed position, said receiving block being provided with a shoulder to engage the member upon which it is mounted to prevent the movement of the notch beyond the horizontalplane of said extension when the door is-opened,

In testimony whereof I aiiix my signature in presence of two witnesses.

HENRY SCHERER. Witnesses O. H. BnoWN, E. S. COLEMAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G.

Images