IMPROVEMENTS IN DOOR LOCKS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said Johan Mathisen at the Office
of the Commissioners of Patents on the 3rd April 1882.
JOHAN MATHISEN, of Christiania, Norway, IMPROVEMENTS IN DOOR LOCKS,
The invention relates to latch door locks and consists in constructing such locks
in the following manner. When using metal latches, I mako the latch hollow at
its front part and place a conical pin therein, which serves to secure the latch by
means of a screw thread. The axle is round and enclosed in a tube as far as it is
not enclosed in the lock, said tube being soldered to the partitions of the lock.
The axle is rigidly connected with a bolt-arm. Two shoulders are provided in the
lock for giving steadiness to the bolt-arm. The bolt-arm does not actuate the bolt
directly, but it acts on an intermediate lever provided with two hooks or pro-
jections one gearing into a suitable hole, in the bolt-arm the other into a hole in
the bolt. The intermediate lever is provided moreover with a projection carrying
a pin which is guided in the partition of the lock said pin being surrounded by a
spiral spring, which serves for supporting the latch when at rest, in which case
the bolt arm rests on a support which at the same time keeps the lid of the box
shut. The bolt is provided at its lower surface with a hollow for placing another
pin and spring serving for shutting the lock, when the door is slammed. The
handle of the latch may be made also of glass, wood &c, in this case the pin must
pass right through the handle and be secured outside by a nut-In order to adapt
this system of a lock for being shut with a key, without applying an additional
bolt, I arrange another lock inside the same box-If the bolt of this lock is moved
by a key it gears into a suitable groove of the main bolt and the lock is closed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Johan Mathisen in the Great Seal Patont Office on the 2nd October
1882.
JOHAN MATHISEN of Christiania, Norway IMPROVEMENTS IN DOOR LOCKS
My invention has for its object the production of a doorlock which combines
facility of manufacture with durability.
The lock with the handle is represented by the accompanying drawings in which
corresponding parts are designated by the same letters. Fig. 1. illustrates the
door-handle and its attachment to the spindle. Fig. 2 is a section of the lock
along the line A-B of Fig: 3. Fig 3 is an elevation of the lock the coverplate
and sleeve being removed, and the auxiliary lock h shown in section. Fig 4
represents a partial section along line C-D of Fig. 3. Fig 5 is a front elevation
and Fig. 5 a side elevation of the counterplate laid into the doorpost (also seen in
Fig 6) Fig 6 is a plan of the lock with section of counterplate along line E E of
Fig 5. Figures 7 to 11 show a modified construction of the lock in views
corresponding to those of Figures 1 to 5. (the section" Fig 6 is not represented).
This lock unlike most other locks is adapted to be attached to the outside of the
door if the latter opens towards the inside, and to the inside of the door, if the
same opens toward the outside. Owing to this arrangement the lock is secured
by screws from the opposite side of the door (screw m Figures 4 and 10), and if
applied to a house door opening towards the outside, which is a rare case the mode
of attachment must be modified. This modification requires only ordinary judgment
and need not therefore be described. A distinctive feature of my lock is also the
large sliding surface with which the arm a¹ on the spindle a rests against the
bosses a all of the lock plates (Fig 2) This prevents any longitudinal dislocation
of the spindle and renders wear and tear and consequent loosening of these parts
almost impossible. To these bosses all all are secured the tubes or sleeves b
forming excellent bearings for the spindle which is round on its whole length and
suffers almost no wear and tear by its rotary motion in consequence of the large
bearing surface. The bearing of the spindle becomes more perfect and durable in
proportion as the distance between the handle and the surface of the door increases
while in ordinary locks the reverse is the case.
This construction also renders one independent of the strength of the door, an
advantage not shared by ordinary mortice locks. The handle d is fixed to the
spindle a by means of a screw-threaded conical pin c (Figs 1 and 7) If the handle
becomes loose in course of time, the conicity of the pin c renders it easy to repair
the defect by screwing the pin further into its socket. This construction thus
avoids the common drawback of wooden, glass or other non-metallic handles
secured to metallic spindles. In order to give to the visible portion of the lock a
uniform appearance, the tube b may be masked by a collar k, which may be loose
and made of any convenient material. The arm 'a' fixed on the spindle a is con-
nected with the latch f by means of the specially shaped link e which rests with
knife edges e ell in corresponding sockets (Fig 3), thereby avoiding all friction
and wear and tear. The two springs e serve respectively for shooting or closing
the latch and for maintaining it in position (by means of the link c) when the door
is thrown in its lock. The latch of this lock has also a peculiar shape, as it
encloses the two helical springs e and the link e, as well as the end of the
arm a which enters through an aperture in the base of the latch, (fig 2 and 3).
The advantage of this arrangement is saving of space and large sliding surfaces
between the latch and its guides,

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The lock case and cover are held together by a single screw i situated near the
centre of the lock. In a similar manner the lock is secured to the door by a single
screw m, which, as already mentioned, is inserted from the opposite side of the
door, where its head abuts against a small platen which also serves to cover the
joint between the tube band the door as well as the key hole. For further securing
the lock in its place the two projections or arms (Figs 4, 3 and 6) are applied to
the top and bottom of the lock case, the oblique faces of which projections come in
contact with the oblique faces of corresponding recesses in the door frame, so as to
prevent any shifting of 'the lock parallel with the door, when the screw mis
tightened. From the position of this lock with regard to the door it is evident
that the width of the contact plate measured between the contact face (abutment
for the latch) and the edge of the doorpost should vary with the thickness of the
door. For this reason the counter-plate (Figs 5, 5 and 6) is composed of two
parts p and p, the outer one of which pl is fastened in such a position that its
edge pcoincides with the closing edge of the door or doorpost, while the inner
piece p¹ may be shifted until its contact face coincides with that of the doorlatch.
If after some deformation of the door the latch does no longer fit the counterplate,
the latter can be easily adjusted.
The drawing shows two different forms of this counterplate, Fig 5, 5 and 6 and
figures 11 and 11. corresponding to two different arrangements of locks, but it is
evident, that other modifications may be made without departing from the principle
of this invention.
In order to prevent the unauthorised opening. of the lock two different devices
are shown, each of which may be used separately or in combination with the other.
One of these devices consist of an independent safety lockh laid into the same
casing as the principal lock and fastened by a single screw. This safety lock has a
key which moves a bolt 1 so that the latter in its closed position prevents the
latch from being moved by the handle. The door is thus locked without requiring
for this purpose a special latch. The auxiliary lock h, while retaining its external
shape, may have any suitable more or less complicated construction, consequently it
may be made independently of the mainlock, and may be easily removed, repaired
or exchanged without exchanging the main lock or removing it from the door. As
this auxiliary lock requires but little strength, its key may be made much smaller
and lighter than an ordinary door key. The second device for locking the main
action can only be used from the inside of the door, so as to replace a nightbolt.
It consists of a pin generally attached to the lock by a small chain (or other suitable
means) and inserted into the sleeve of the spindle o Figs 2 and 8 for preventing
the motion of the latter For several kinds of locks such a locking device is
perfectly sufficient, in which case the size and price of the lock can be considerably
reduced. The modified lock represented in Figures 7 to 11 has substantially the
same construction and consequently also the same peculiarities as described above
for the first modification, with the difference however, that in this lock the latch is
arranged to slide vertically. This arrangement has the advantage that the breadth
of the lock may be considerably reduced, whereby the lock is rendered applicable
to doors with very narrow frames, which occur frequently. In consequence of this
arrangement the counter-plate must obtain a somewhat different shape, as will be
seen from the drawings Figs 11 and 11ª which need no further explanation.
1. Door locks adapted to be applied and secured to the side of the door. opposite
0 to that towards which the door opens.
2. In door locks a loose collar surrounding and masking the tube or sleeve b.
3. In door locks a link e provided with knife bearings e¹ e¹¹ for connecting the
operating arm a¹ with the latch.
4. In door locks the peculiar hollow shape of the latch.

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5. Door locks provided with two projections or lugs and a single screw m for
securing the lock in position.
6. The method of keeping the two parts of a lock case together by a single
screw i.
7. In combination with doorlocks two counterplates p₁ and p" made adjustable
as regards their relative position.
8. In door locks the method of locking the latch by means of an independent or
auxiliary lock h and key
9. The modified construction of doorlocks represented by Figures 7 to 11 with
vertically sliding latch.
In witness whereof I the said Johan Mathisen have hereunto set my hand and
seal this twenty-eighth day of September A.D. 1882.
JOH MATHISEN (L.S.)