Mortise and tenon joint

Each construction member comprises a pair of mutually opposing, normally strip-like bodies of wood or other fastener impalable material, which are abutted face-to-face with one another on a common axis and adapted to define an axially extending slot at the interface therebetween. It also comprises an elongated strip of metal-like reinforcing material which is interposed in the slot and equipped with integral tooth-like fasteners on the longitudinally extending edges thereof which are oppositely disposed to one another from edge-to-edge of the strip and impaled in the bodies of fastener impalable material adjacent opposite sides of the slot. To this extent, pairs of the members may be modular. However, where a pair of members are to be interengaged with one another in a mortise and tenon joint, then the bodies of fastener impalable material in one of the members are coterminated with one another at corresponding axial ends thereof, and the metal-like strip therebetween is projected beyond the terminal ends of the bodies to form a tenon on that end of the member. Moreover, the bodies of fastener impalable material in the other member are adapted so that they define a cross-axial groove at the interface therebetween, which is disposed on the opposite side of the interface from the axially extending slot in the respective member, and opens into one axially extending edge of the member to form a mortise for the tenon of the first mentioned member.

THE INVENTION IN GENERAL 
This invention relates to a laminated, metal reinforced construction 
member; and in particular to a construction member of this nature which 
has a mortise and tenon joint forming capability between pairs thereof. 
According to the invention, each construction member comprises a pair of 
mutually opposing, normally strip-like bodies of wood or other fastener 
impalable material, which are abutted face-to-face with one another on a 
common axis and adapted to define an axially extending slot at the 
interface therebetween. It also comprises an elongated strip of metal-like 
reinforcing material which is interposed in the slot and equipped with 
integral tooth-like fasteners on the longitudinally extending edges 
thereof which are oppositely disposed to one another from edge-to-edge of 
the strip and impaled in the bodies of fastener impalable material 
adjacent opposite sides of the slot. Each may also include a layer of 
adhesive material which is disposed at the interface between the bodies of 
fastener impalable material to form an adhesive bond therebetween. Also, 
if the metal strip and slot are complimentary in size and cross section, 
there may be layers of adhesive material on the aforementioned sides of 
the slot, to form a bond between the metal strip and each of the bodies of 
fastener impalable material. 
Preferably, all of the fasteners on each edge of the metal-like strip are 
oppositely disposed to those on the other edge. 
To this extent, pairs of the members may be modular. However, where a pair 
of members are to be interengaged with one another in a mortise and tenon 
joint, then the bodies of fastener impalable material in one of the 
members are coterminated with one another at corresponding axial ends 
thereof, and the metal-like strip therebetween is projected beyond the 
terminal ends of the bodies to form a tenon on that end of the member. 
Moreover, the bodies of fastener impalable material in the other member 
are adapted so that they define a cross axial groove at the interface 
therebetween, which is disposed on the opposite side of the interface from 
the axially extending slot in the respective member, and opens into one 
axially extending edge of the member to form a mortise for the tenon of 
the first mentioned member. In addition, the fasteners are normally 
removed from the tenon of the first mentioned member, and the cross axial 
groove in the mortised member is adapted so that it is complimentary in 
size and cross section to the body of the tenon, to slidably receive the 
same. 
The cross axial groove may intersect the slot at the interface of the 
mortised member, and in such a case the fasteners on the metal strip in 
the mortised member may also be removed from the same at the groove, to 
enable the tenon to slide face-to-face with the metal strip when the tenon 
is inserted in the groove. Additionally, the groove in the mortised member 
may open into the opposing axially extending edge of the member, so that 
it forms a slot between the respective edges of the member. 
In the presently preferred embodiments of the invention, one of the bodies 
of fastener impalable material in each construction member is plain-faced 
and the other has an axially extending groove in the face thereof, so that 
together they define the slot for the metal-like strip. Also, where a 
member is mortised, the cross axial groove is formed in the plain-forced 
body of fastener impalable material, so that the cross axial groove is 
disposed on the opposite side of the interface from the axially extending 
slot for the metal strip therein. 
Normally, the various grooves and metal strips are flat and rectangular in 
cross section, and are complimentarily sized. The metal strips have 
indentations in the longitudinally extending edges thereof, formed by 
cutting and bending the metal-like material of each relatively out of the 
main body plane of the strip at the sites of the fasteners, to form the 
same. Preferably, the fasteners are bent at right angles to the main body 
plane of the strip. 
Since the fasteners on the tenon are removed, it has indentations in the 
longitudinally extending edges thereof at the sites of the fasteners, but 
its faces are plain and flat. 
After a mortise and tenon joint is made between two of the members, they 
may be rigidly interconnected with one another by inserting a pin in 
registering holes in the tenon and the mortised member, respectively. 
Also, the pin may be of longer length than the cross sectional width of 
the mortised member, and may be equipped with a clamping means such as a 
nut and bolt combination, to clamp the assembly together at the 
connection. Alternatively, the pin may be of lesser length than the cross 
sectional width of the mortised member, and the pin connection may be 
concealed within the joint by adding plugs to the holes in the mortised 
member, after the pin has been inserted across the joint.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawing, it will be seen that the frame 2 (FIG. 1) 
comprises a pair of rafter-like chordal members 4, and a collar-like cross 
member 6. The rafter-like members 4 rest on a pair of supports 8, and the 
collar-like member 6 is interconnected at its ends with and between the 
rafter-like members. Each connection between the members takes the form of 
a mortise and tenon joint, such as one of those illustrated at 10 and 10' 
in FIGS. 4-6. The joint is made by modifying the collar-like member to 
form a pair of tenons 12 on the respective axial end thereof, and by 
engaging the tenons in a pair of mortises 14 midway in the length of the 
adjacent rafter-like member, as shall be explained. 
Basically, the three members 4 and 6 are modular in construction. Each 
comprises a pair of mutually opposing strip-like bodies 16 (FIG. 2) of 
wood or other fastener impalable material, and the bodies 16 are abutted 
face-to-face with one another (FIG. 3) on a common longitudinal axis and 
adapted to define a pair of spaced axially extending slots 18 at the 
interface therebetween. Each member also comprises a pair of elongated 
strips 20 of metal-like reinforcing material which are interposed in the 
slots 18 and are complimentary in size and cross section with the same. 
The strips are equipped with integral tooth-like fasteners 22 on the 
longitudinally extending edges thereof, and the fasteners are oppositely 
disposed to one another from edge-to-edge of the respective strips, and 
impaled in the bodies 16 of fastener impalable material, adjacent opposite 
sides of the respective slots 18. There is also a layer of adhesive 23 
(FIG. 2) in each member at the interface 24 between the bodies of fastener 
impalable material; and layers 26 of adhesive material on the 
aforementioned sides of the slots, so that the metal strips and bodies of 
fastener impalable material are all adhesively bonded together in the 
member. 
More specifically, one of the bodies 16 of fastener impalable material is 
plain-faced and the other has a pair of spaced axially extending grooves 
28 in the face thereof, so that together they define the slots 18 for the 
metal strips 20. Also, the respective grooves 28 and strips 20 are flat 
and rectangular in cross section, and each strip 20 has indentations 30 in 
the longitudinally extending edges thereof, formed by cutting and bending 
the metal-like material of the same, relatively out of the main body plane 
of the strip at the sites of the fasteners 22 to form the same. 
When each joint 10 or 10' is made, the bodies 16 of fastener impalable 
material in the collar-like member 6 are coterminated with one another at 
corresponding axial ends thereof, and the metal-like strips 20 
therebetween are projected beyond the terminal ends of the bodies to form 
the tenons 12 on that end of the member. Moreover, the bodies 16 of 
fastener impalable material in the adjacent rafter-like member 4 are 
adapted to define a pair of spaced, parallel cross axial grooves 32 at the 
interface therebetween, which are disposed on the opposite side of the 
interface from the axially extending slos 18 therein, and open into one 
axially extending edge of the member 4, to form the mortises 14 for the 
tenons 12 of the collar-like member 6. In addition, the grooves 32 and 
tenons 12 are adapted so that they are complimentary in size and cross 
section, and the fasteners 22 on the strips 20 of the collar-like member 
are removed from the tenon portions of the same, so that the tenons can be 
slidably inserted in the mortises. Preferably, the grooves 32 in the 
rafter-like member also open into the opposing axially extending edge of 
the member, so as to form slot-like mortises between the edges thereof; 
and the fasteners 22 on the metal strips 20 in the member are stripped 
from the same at the grooves, to enable the tenons to slide face-to-face 
with the strips, and in fact, past the strips to the opposite ends of the 
mortises. 
After a joint is made between a pair of members, they are rigidly 
interconnected by pinning them together at registering holes 34 and 36 in 
the rafter-like member and the tenons of the collar-like member, 
respectively. The pin for the connection may be of longer length than the 
cross sectional width of the rafter-like member, as in FIGS. 4 and 5 where 
nuts 38 and bolts 40 are employed to clamp the assembly together. 
Alternatively, a pin 42 of lesser length than the width of the rafter-like 
member, may be concealed within the joint by inserting plugs 44 and 48 in 
the holes of the rafter-like member, to conceal the connection. See FIG. 
6. 
The members are normally fabricated by assembling the bodies 16 and strips 
20 in a press, and compressing the assembly to fasten and bond the 
respective components to one another. The strips may be sized to project 
at one or both ends of the assembly, to form the tenons; or the bodies of 
a member may be cut-down at the point of use for this purpose. Normally, 
the cross axial grooves 32 are formed in the plain-faced body at the time 
of assembly. 
In other preferred embodiments of the invention, the fasteners 22 are 
alternately oppositely disposed along each longitudinally extending edge 
of the strips 20.