US2290855A

US2290855A - Timber connector

Info

Publication number: US2290855A
Application number: US316860A
Authority: US
Inventors: James E Myer
Original assignee: Timber Engineering Co
Current assignee: Timber Engineering Co
Priority date: 1940-02-01
Filing date: 1940-02-01
Publication date: 1942-07-28
Anticipated expiration: 1959-07-28

Description

July 28, 1942. M v 2,290,855

- TIMBER CONNECTOR Fil ed Feb. 1,1940 2 Sheets-Sheefl Jami/gm! y 1942- 7 J. E. MYER 2,290,855

' TIMBER CONNECTOR Filed Feb. 1, 1940' 2 Sheets-Sheet 2 Jamal/{(5 0 Patented July 28, 1942 UNIT ED 1 STATES PATENT OFFlC E I TIMBER CONNECTOR James E. .Myer, Washington,.,D. 0., assignor to Timber fEn'gineering Company, .Washington, 3 D; 0., a corporation of Delaware Application February 1, 1940, Serial No. 316,866

. 2 'Claims.

The invention relates to timber connectors of the spur and grid type and has as an object the improvement upon connectors of this type in details.

It is a further object of the invention to provide a connector which is of greater strength for the same amount of metal than former connectors of the same type.

It is a further object of the invention to provide a connector that will sink into the wood more easily than former connectors.

Further objects of the invention will appear from the following description when read in connection with the accompanying drawings showing illustrative embodiments of the invention, and wherein:

Figure 1 is a plan View;

Fig. 2 is a side elevation;

Fig. 3 is a vertical section on broken line 33 of Figure 2;

Fig. 4 is an enlarged detail section on line i4 of Figure 1;

Fig. 5 is a plan view of a form of the invention embodied in a rectangular connector;

Fig. 6 is an edge View of the structure of Figure 5; and

Fig. 7 is a vertical section on broken line 1-7 of Figure 5.

As shown in Figures 1 to 4 inclusive, the grid device comprises an outer ring In and an inner ring H joined by radiating arms l2.

Spurs or studs to enter the wood and increase the resistance to movement between a pair of connected timbers are shown at I3 and as shown are placed at the points of intersection of the arms l2 with the ring In.

The studs 13 are shown as bluntly pointed at M and as tapering from their junction with ring H! to the pyramidal pointed portion.

Many tests to destruction of connectors of this type while in place between timbers show points of breakage of the rings and the design of the resent invention has been provided to strengthen the structure at the thus discovered points of probable breakage without the placing of excess metal at other points.

To allow the ring to be sunk more readily into the meeting surfaces of the timbers, the ring IE] is shown as of greater height than radial extent. Also the radial thickness of this ring is greater at the points [5 of the junction with the studs 13 than at the points [6 midway between the studs. As shown this difference of radial thickness is provided by forming the exterior of the rings between the studs upon the arc of a circle of very considerably greater radius thanis the ring itself, and furtherby making the inner surfaces of these arcs of the ring upon a smaller radius of curvature than the radius of the ring itself.

Since the strain upon the ring H is not increased in the form shown, by the presence of any studs rising therefrom, this ring is made of less axial extent or height than is the ring I5] and the arms I2 are also tapered toward the axis of the ring, as clearly appears from Figures 1 and 3.

Figures 5 to '7 inclusive show the invention embodied in a rectangular grid and spur connector. As there shown the spurs l3, in themselves formed as described above, are located at the intersections of the ribs 25. The ribs are of greater verticalor axial-than horizontal extent, as shown by the sections of Figure '7, at 26, and moreover are of greater horizontal extent at their ends, or points of junction with the spurs than at their middle portions, as clearly shown in Figure 5 and following the principle set forth in connection with the ring 10.

The tests of connectors referred to show that the point of breakage thereof as heretofore made and used, is at the junction of the ribs or rings with the spurs, caused by tipping of the spurs when the timbers are forced to slide relative to each other. The ribs intermediate the spurs have been made stronger than required.

The form of the present invention moves this excess metal at the middle of the length of the ribs Or rings toward the ends thereof where it is needed and changes the form of both ribs and spurs at the junctions. Thus the ring I!) and the ribs 25 at their ends are formed at each cutting edge with a filet l1 and the ends of the radial ribs I2 are formed likewise.

The spurs It, as shown in Figures 1 to 4, are also formed with what may be termed a filet [9 toward the junction with the ribs l2. In the form of Figures 5 to 7 such filets H! are shown toward each rib intersecting or joining the spurs.

The filets l9, as shown in Figure 4, increases the metal at the junction of the spurs and ribs, to the extent shown between the point 21 and the point 28, Figure 4. When this extent is compared with the metal of the old practice, or with the distance between the point 21 and the point 29, the increase of metal at the junctionsthat is strength to resist breakage at this point is substantially Connectors of the type illustrated are used in large numbers, and in good-sized structure run into the thousands. Te be commercial the cost thereof must be kept as low as possible which can only be done by forming them of cast metal usually cast iron.

To this end the molds are formed from pattern plates carrying the patterns for a plurality of connectors fed from a common sprue which means that the molten metal for each connector enters the mold cavity from a single sprue channel from which it must flow from channel to channel and into the cavity for each spur.

The fractured connectors from the tests to destruction of the old form of connectors indicates that the metal at the points of breakage is not as good as it might be. The enlargements provided by the filets I! and I9 providebetter flow of metal and larger masses of molten metal at these points, which will not chill as promptly as before, thus resulting in greater soundness of the metal at these crucial points-still further in- 20 creasing the strength of the finished structure.

Minor changes may be made in the physical embodiments of the invention within the scope of the appended claims without departing from the spirit thereof.

I claim:

1. A timber connector comprising: a grid formed with intersecting arms presenting timbercutting edges and with spurs rectangular in cross section, at the intersections; inward portions of inwardly extending of said arms of less thickness transversely, than the widths of said spurs at their junctions with said arms, and increasing to a thickness equal to widths of said spurs at their juncture therewith; the equal-to-spur thickness of said arms flaring from a point spaced from the spurs to the said junction, and presenting plane surfaces to resist timber movement.

2. The structure of claim 1 with the thickness of peripheral arms of the grid substantially equal to widths of the spurs at their juncture therewith and tapering to a less thickness midway between the spurs.

JAMES E. MYER.