Improvements in the Breech Mechanism of Guns.
Year: 1892

page_text: Date of Application, 12th May, 1892
Complete Specification Left, 22nd Sept., 1892-Accepted, 22nd Oct., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Breech Mechanism of Guns.
I, AXEL WELIN of the Scandinavian Sailors' Temperance Home, Garford
Street in the County of Middlesex, Mechanical Engineer, do hereby declare the
nature of this invention to be as follows:-
:-
The mechanism is operated by a handle fixed to a transverse axis supported in
bearings at the rear end of the gun. This axis is free both to turn and also
to move endwise in the bearings and has upon it a worm (gearing with a worm
wheel upon an axis to which is fixed a pinion gearing with a longitudinal rack
upon the breech block) and also a number of collars forming a rack gearing with a
ring of teeth upon the rear end of the breech block.
When the breech block is screwed home the worm wheel cannot turn because its
turning involves longitudinal motion of the breech block and therefore during the
first movement of rotation of the handle the worm wheel acts as a nut for the worm
to work in so that the rotation causes the handle to move lengthwise and thus
When this movement has
by reason of the collars upon it rotates the breech block.
continued for a sufficient time to have unlocked the divided screws on the breech
block from the corresponding screws in the breech a collar on the handle comes
against an abutment and its further movement lengthwise is prevented. Its
continued rotation causes the worm wheel which is now free to turn to revolve and
the pinion upon its axis gearing with the longitudinal rack withdraws the breech
block from the gun onto a table or platform which with the carrier ring is pivotted
on the axis of the worm wheel. When the breech block is fully withdrawn the
pinion comes to the end of the rack and its continued rotation swings the breech
block with the table and carrier ring rearwards exposing the opening of the breech.
The bearings of the axis of the worm wheel are in the form of slots and when the
breech block is withdrawn the axis is free to move to one side in these slots and is
caused to do so by reason of teeth upon two discs fixed to it coming at this time into
gear with two small transverse racks, in this way the breech block is carried to one
side well clear of the breech opening.
The worm wheel has in it a circular slot with a notch at one end. A bolt upon
a slide working in a groove in the table lies in this slot. At the other end of the
slide there is an inclined lug which when the breech is closed lies in an inclined
fork fixed to the gun and holds the bolt out of the notch.
begins to separate from the gun the lug moves along the
the bolt into the notch so that the worm wheel is locked
swung back against the gun.
When however the table
inclined fork and draws
until the table is again
At the end of the axis of the handle there is a disc the edge of which when the
breech is open
lies in a groove in a toothed pinion. The axis carries a single tooth
which once in every revolution comes into gear with the teeth of the pinion giving
to the latter a slow step by step motion of rotation. At one point the pinion is cut
away on one side and when the disc on the axis comes to this point but not till then
it can escape from the groove and longitudinal motion of the axis becomes possible.
This arrangement ensures that in closing the breech the worm wheel shall perform
the whole number of revolutions necessary for carrying the breech block longi-
tudinally into the gun before the axis of the handle can move lengthwise to turn
the breech block and engage the divided screws.
Dated this 11th day of May 1892.

page_text: COMPLETE SPECIFICATION.
Improvements in the Breech Mechanism of Guns.
I, AXEL WELIN of the Scandinavian Sailors' Temperance Home, Garford
Street in the County of Middlesex, Mechanical Engineer, do hereby declare
the nature of this invention and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement :-
The mechanism is operated by a handle fixed to a transverse axis supported_in
bearings at the rear end of the gun. This axis is free both to turn and also
to move end wise in the bearings and has upon it a worm (gearing with a worm
wheel upon an axis to which is fixed a pinion gearing with a longitudinal rack upon
the breech block) and also a number of collars forming a rack gearing with a ring
of teeth upon the rear end of the breech block.
When the breech block is screwed home the worm wheel cannot turn because its
turning involves longitudinal motion of the breech block and therefore during the
first movement of rotation of the handle the worm wheel acts as a nut for the worm
to work in so that the rotation causes the handle to move lengthwise and thus by
reason of the collars upon it rotates the breech block. When this movement has
continued for a sufficient time to have unlocked the divided screws on the breech
block from the corresponding screws in the breech a collar on the handle comes
against an abutment and its further movement lengthwise is prevented. Its
continued rotation causes the worm wheel which is now free to turn to revolve and
the pinion upon its axis gearing with the longitudinal rack withdraws the breech
block from the gun onto a table or platform which with the carrier ring is pivotted
on the axis of the worm wheel. When the breech block is fully withdrawn the
pinion comes to the end of the rack and its continued rotation swings the breech
block with the table and carrier ring rearwards exposing the opening of the breech.
The bearings of the axis of the worm wheel are in the form of slots and when the
breech block is withdrawn the axis is free to move to one side in the slots and is
caused to do so by reason of teeth upon two discs fixed to it coming at this time into
gear with two small transverse racks, in this way the breech block is carried to one
side well clear of the breech opening.
The worm wheel has in it a circular slot with a notch at one end. A bolt upon
a slide working in a groove in the table lies in this slot. At the other end of the
slide there is an inclined lug which when the breech is closed lies in an inclined
fork fixed to the gun and holds the bolt out of the notch. When however the table
begins to separate from the gun the lug moves along the inclined fork and draws
the bolt into the notch so that the worm wheel is locked until the table is again
swung back against the gun.
At the end of the axis of the handle there is a disc the edge of which when the
breech is open lies in a groove in a toothed pinion. The axis carries a single tooth
which once in every revolution comes into gear with the teeth of the pinion giving
to the latter a slow step by step motion of rotation. At one point the pinion is cut
away on one side and when the disc ou the axis comes to this point but not till then
it can escape from the groove and longitudinal motion of the axis becomes possible.
This arrangement ensures that in closing the breech the worn wheel shall perform
the whole number of revolutions necessary for carrying the breech block longi-
tudinally into the gun before the axis of the handle can move lengthwise to turn
the breech block and engage the divided screws.
DESCRIPTION OF THE DRAWINGS.

page_text: elevation, figure o a side elevation, and Figure a norizontal
section of the same gun with the breech mechanism removed.
Figure 8 is a rear elevation, Figure 9 a side elevation, and Figure 10 a longi-
tudinal section of the breech block.
Figure 11 is a plan, Figure 12 a rear elevation partly in section, Figure 12 a
section on the line 1. 1. Figure 12, and Figure 13 a side elevation of the carrier
ring and table.
Figure 14 is a side elevation of the handle and axis, and Figure 15 is a section on
the line 2. 2. Figure 14.
Figure 16 is a longitudinal vertical section and Figure 17 a plan of the worm
wheel and pinion, and Figure 18 is a section on the line a a in Figure 16.
Figure 19 is a side view, and Figure 20 an end view of the axis of the worm
wheel, and Figures 21 and 22 shew the friction roller upon it.
Figure 23 is a side elevation, and Figure 24 a plan of the bolt.
Figure 25 is an elevation of the end of the handle and the pinion for locking it,
and Figure 26 is a side elevation of the latter. These two views are drawn to twice
the scale of the others.
Figure 27 is a part plan and Figure 28 a rear elevation shewing a modification.
A is the rear end of the gun which has a bole A bored in it to receive the
axis B of the handle. This axis has upon it (see Figures 14 and 15) a worm B', a
number of collars B, a long single toothed pinion B³ and a disc B. C Figures 8
to 10 is the breech block.
This is of the construction described in the Specification of my former Patent
No. 11417 of the year 1891. C¹ C¹ are two similar segments or groups of screw
threads on the periphery of the block and on opposite sides of it. Č² C³, C³C³, are
also pairs of similar segments. CC are spaces where there are no screw threads.
Each segment occupies about one eighth of the circumference of the block.
The screw threads C¹ C' are of smaller radius or nearer to the centre of the block
than the screw threads C C, similarly the screw threads C C are nearer to the
centre than C³ C³.
The breech of the gun has corresponding segments of screw threads within it.
When the breech block is turned in the breech of the gun through an arc of 45°
the screw threads C' assume the position previously occupied by the screw
threads C but being of smaller diameter do not engage with the threads within the
breech of the gun. Similarly the screw threads C2 pass to the position previously
occupied by the screw threads C and likewise do not engage. At the same time
the screw threads C* pass to the blank segments in the breech of the gun. The
breech block may then be drawn rearwards out of the gun. Similarly when
the breech block is replaced a rotation through an arc of 45° locks it securely.
The breech block also has upon it a longitudinal rack C the last few teeth at the
rear end of which are longer than the other teeth as shewn at Figure 9 and a
portion of a ring of teeth C Figures 8 and 9 which gear with the collars B' on the
axis B of the handle.
The breech block C is supported by the carrier ring D and cradle or table D¹
Figures 11 to 13. This ring and table are hinged to the gun by an axis E
(Figures 19 and 20) having upon its ends pinions E' partly toothed and partly plain
discs (Figures 1, 4, 11 and 12) which work in slots in brackets A' (Figures 1 to 7)
fixed on the rear end of the gun. On one side of the slots are racks A³ which
gear with the teeth upon the pinion E. The axis E also has at its upper end a
friction roller E' and near its lower end a worm wheel F made in one piece with the
pinion F. The worm wheel F gears with the worm B' on the axis B of the handle
and the pinion F' with the longitudinal rack C' on the breech block.
The
G Figures 23 and 24 is a bolt working in a slot in the underside of the table D'.
This bolt has lugs G₁ and G' upon it. The lug G' either lies in a circular slot F
in the worm wheel F or else engages with a notch F at one end of this slot.
lug G when the table D¹ is in contact with the breech of the gun lies in an inclined
notch in a bracket A' fixed to the gun.

page_text: H Figures 25 and 26 is a pinion mounted on the axis H' fixed to the gun. The
edge of this pinion is slotted to receive the disc B' fixed at the end of the axis B of
the handle, the teeth have circular concave tops in which the cylindrical part
of the single toothed pinion B' lies so that the pinion H cannot turn until the tooth
of the pinion B³ comes into gear with it.
The action of the apparatus is as follows:-
When the breech block C is screwed home the worm wheel F cannot turn
because it is geared to the block by the pinion F¹ and rack C' so that its turning
involves the longitudinal motion of the breech block which is at this time impossible
and therefore during the first movement of rotation of the handle to open the breech
the worm wheel F acts as a fixed nut for the worm B¹ to work in so that the
rotation causes the handle to move lengthwise of itself and thus by reason of the
collars B gearing with the teeth C causes the breech block C to rotate and
disengage its screws C1, C2, C3, from the corresponding screws in the breech.
When this has been done the end dise B comes against a stop and prevents any
further longitudinal motion of the handle B. As the handle is coming to the end
of its longitudinal travel the disc B₁ at its end passes through the notch H* in the
outer side of the pinion H into the central slot in the curved face of the pinion.
The breech block has now been unlocked and the worm wheel F freed the
continued rotation therefore of the handle causes the latter to rotate and since the
pinion F fixed to it is in gear with the rack C on the breech block this is
withdrawn rearwards. It is to be observed that each rotation of the handle after
its longitudinal motion has ceased moves the pinion H through a space equal to
one tooth and carries the notch H2 away from the disc B₁ so that the axis of the
handle cannot again move longitudinally until an equal number of turns in the
reverse direction have been given to it. When the block is fully withdrawn
the notched end of the slot F2 in the worm wheel F comes against the lug G¹ on the
bolt G and prevents it from any longer turning relatively to the table D', its
further rotation therefore causes the table D' and carrier ring D with the breech
block C to swing back rearwards about the axis E. As the table D' comes away
from the breech of the gun the inclined slot in the bracket A acting on the lug G'
on the bolt G draws the bolt to the right (Figures 1 and 3) causing the lug G¹ to
enter the notch F³ in the worm wheel locking the latter firmly to the table D'. At
this time also the pinions E¹ on the axis E come into gear with the racks A³ and in
this way the breech block as it swings back is also carried to one side well clear of
the breech opening as shewn in Figure 4.
In closing the breech the reverse takes place :-the breech block swings back
and as the table D' comes against the gun the bolt G is withdrawn freeing the
worm wheel F whose movement, through the pinion F¹, runs in the breech block.
When this has been done the end of the slot F' comes against the lug G¹ and
arrests the rotation of the worm wheel F', the notch H2 has now however come
back to the disc B* and freed the handle longitudinally so that its continual rotation
turns and locks the breech block.
In the modification shewn in Figures 27 and 28 the slot in the bracket A
inclines in the opposite direction to that just described, the circular slot F in the
worm wheel F and the lug G¹ are omitted and the notch F is made in the periphery
of the wheel instead of in the slot. In this case when the table D' comes away
from the breech, the bolt G is moved to the left its end entering the notch F³ thus
locking the worm wheel to the table as before.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. In breech mechanism for guns the combination of a breech block locked and
unlocked by a partial turn, a longitudinal rack upon the breech block, a pinion
gearing with the rack, a support for the block when withdrawn hinged to the axis
of the pinion, a rack upon the gun and teeth upon the said axis which come into

page_text: gear with the rack after the block has been withdrawn and carry it and the support
to one side clear of the opening of the breech.
2. In breech mechanism for guns the combination of a breech block locked and
unlocked by a partial turn, a handle free to rotate and also to move longitudinally,
gearing connecting the handle and block in such manner that the longitudinal
movement of the handle turns and unlocks the block and gearing also connecting
the handle and block in such manner that the rotation of the handle when the block
is unlocked moves the block longitudinally.
3. In breech mechanism for guns the combination of a breech block locked and
unlocked by a partial turn, a ring of teeth and a longitudinal rack upon the block,
a handle free to rotate and also to move longitudinally, collars on the handle
gearing with the ring of teeth on the block, a worm on the handle, and a worm
wheel gearing with the worm and connected to a pinion gearing with the rack upon
the block.
4. In breech mechanism for guns the combination of a breech block locked
and unlocked by a partial turn, a ring of teeth, and a longitudinal rack on the
breech block, a handle free to rotate and also nove longitudinally, collars on the
handle gearing with the ring of teeth on the block, a worm on the handle, a worm
wheel gearing with the worm and connected to a pinion gearing with the rack upon
the block, and a table or support for the block when withdrawn hinged to the axis
of the worm wheel.
5. In breech mechanism for guns the combination of a breech block locked and
unlocked by a partial turn, a ring of teeth and a longitudinal rack on the breech
block, a handle free to rotate and also to move longitudinally, collars on the handle
gearing with the ring of teeth on the block, a worm on the handle, a worm wheel
gearing with the worm and connected to a pinion gearing with the rack upon the
block, a support for the block when withdrawn hinged to the axis of the worm
wheel, a rack upon the gun and teeth upon the said axis which come into gear with
the rack after the block has been withdrawn and carry it and the support to one
side clear of the opening of the breech.
6. In breech mechanism for guns the combination of a breech block locked and
unlocked by a partial turn, a ring of teeth and a longitudinal rack on the breech
block, a handle free to rotate and also move longitudinally, collars on the handle
gearing with the ring of teeth on the block, a worm on the handle, a worm wheel
gearing with the worm and connected to a pinion gearing with the rack upon the
block, a table or support for the block when withdrawn hinged to the axis of the
worm wheel, mechanism for locking the table to the worm wheel when the former
is turned back away from the gun and mechanism for preventing the handle from
moving longitudinally, when the breech is being closed until the block has been run
home longitudinally.
7. In breech mechanism for guns the combination of a breech block locked and
unlocked by a partial turn, a ring of teeth and a longitudinal rack on the breech
block, a handle free to rotate and also move longitudinally, collars on the handle
gearing with the ring of teeth on the block, a worm on the handle, a worm wheel
gearing with the worm and connected to a pinion gearing with the rack upon the
block, a table or support for the block when withdrawn hinged to the axis of the
worm wheel, a bolt in the table, two lugs on the bolt, a circular slot in the worm
wheel receiving one of the lugs and having a notch at one end, an inclined slot in
the gun to receive the other lug, a disc upon the axis of the handle, a pinion on the
gun, a groove in the curved face of the pinion to receive the said disc, a notch in
one side of the pinion to allow the disc to escape at one point from the groove and
means for rotating the pinion slower than the handle.
8. Breech mechanism for guns substantially as described and shown in the
drawings.