Year: 1899

page_text: We, CHARLES PORTWAY, of the Firm of Charles Portway & Son, of the
Tortoise Stove Works and High Street, Halstead, in the County of Essex, Iron
Founders and Stove Manufacturers, and JOHN THOMAS GRAHAM, of 12, Bois
Field, Halstead aforesaid, Engineer, do hereby declare the nature of this inven-
tion to be as follows:-
This invention relates to improvements in jacks, or lifting mechanism such as
is used in lifting the axles of heavy vehicles, motor cars and the like, and for
other like purposes.
This invention is designed to produce an improved jack of the type described in
the Specification of Letters Patent granted to Albert Jackson, dated April 30th
1889, No. 7190, the improved jack now to be described being especially adapted
to lift heavier weights in proportion to its size than in the older construction
referred to and further it is designed to enable successive lifts of the weight to
be effected with greater ease and safety, besides attaining other advantages.
In our improved construction' the shaft is mounted on the base and supports
with capability of its sliding loosely within it the loose bar, which bar carries the
head. The lugs to which one centre of the operating lever is connected, are
carried by the base, and to the other centre of the lever are connected the lower
ends of the connecting links whilst the upper ends of those links are connected
to the rocking-grip, or clutching member which performs the gripping and lifting
operation. To the upper part of the shaft is secured, or formed thereon, a lug
to which is hinged or pivotted a second gripping member, which second gripping
member when the first has clutched and lifted the bar and head, comes into opera-
tion to take a retaining hold on the loose bar and keep it raised in the position it
has been lifted to, whilst the first clutch is released and the upper clutching
member is being lowered to take a fresh hold on the bar by the simple action of
lowering the operating lever.
When it is desired to release the second, or holding clutch member from the
loose bar (which bar is recessed or serrated to facilitate grip) a lever arm mounted
on the shaft head, with a pivotal connection is moved horizontally so as to bring
its inclined end under a correspondingly inclined piece or part on the holding
clutch and thereby lift and disengage its operative side from the loose bar per-
mitting the loaded bar to descend.
By this arrangement the operating lever can be more conveniently arranged
owing to its pivotal point being low and close to the base and when lifted it
swings with greater freedom from the surrounding parts, besides which it can
be more compactly stowed.

page_text: Improvements in Jacks or Lifting Mechanism.
We, CHARLES PORTWAY, of the Firm of Charles Portway & Son, of the
Tortoise Stove Works and High Street, Halstead, in the County of Essex, Iron
Founders and Stove Manufacturers, and JOHN THOMAS GRAHAM, of 12, Bois
Field, Halstead aforesaid, Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
This invention relates to improvements in jacks, or lifting mechanism such as
is used in lifting the axles of heavy vehicles motor cars and the like, and for
other like purposes.
This invention is designed to produce an improved jack of the type described in
the Specification of Letters Patent granted to Albert Jackson, dated April 30th
1889, No. 7190, the improved jack now to be described being especially adapted
.to lift heavier weights in proportion to its size than in the older construction
referred to and further it is designed to enable successive lifts of the weight to
be effected with greater ease and safety, besides attaining other advantages.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 shows an external side view of the jack with the head in a raised
position.
Fig. 2 shows a part section of Fig. 1.
Fig. 3 is a rear view of Fig. 1 looking from the handle side towards the head
thereof.
Fig. 4 shows a sectional view of Fig. 1 with the parts in a different position.
Fig. 5 shows a similar view to Figs. 1 and 4 but with the head lowered and the
handle lever ready to be folded against the pillar.
Fig. 6 is a plan view of Fig. 1 with the head severed from its stem the better
to display the parts.
Fig. 7 is a detail, being a side view to a larger scale than the previously described
figures, of a portion of the stem supporting the head.
In our improved jack construction the shaft 1 is mounted on the base 2 and
supports with capability of its sliding loosely within it the loose bar 3, which
har carries the head 4. The lugs 5, 5, to which one centre 6 of the operating
lever 8 is connected are carried by the base 2, and to the other centre 7 of the
lever 8 are connected the lower ends of the connecting links 9, 9 whilst the upper
ends of those links are connected to the rocking grip, or clutching member 10
which performs the gripping and lifting operation. This operating lever 8 is
articulated (at 11) to enable its outer portion S to be turned on the hinge pin 11
(the locking pin 12 having first been removed from holes passing through both
the inner and outer parts of the lever 8) and the lever can be folded up against
the shaft 1. To the upper part of the shaft 1 is secured, or formed thereon, a
lug 13 to which is hinged or pivotted a second gripping member 14, which second
gripping member when the first gripper 10 has clutched and lifted the bar 3 and
head 4 comes into operation to take a retaining hold on the loose bar 3 and keep
said loose har raised in the position it has been lifted to, whilst the first clutch 10
is released and said upper clutching member is being lowered to take a fresh hold
on the bar 3 by the simple action of lowering the operating lever 8.
When it is desired to release the second, or holding clutch member 13 from the
loose bar 3 (which bar 3 is recessed or serrated to facilitate grip see Fig. 7 where
the serrations are more plainly to be seen) a lever arm 15 mounted on the shaft
head with a pivotal connection 16 is moved horizontally so as to bring its

page_text: inclined end 17 under a correspondingly inclined piece or part 18 on the holding
clutch 14 and thereby, lift and disengage its operative side from the loose bar 3
permitting the loaded bar to descend.
By this arrangement the operating lever 8 can be more conveniently arranged
owing to its pivotal point being low and close to the base 2 and when lifted it
swings with greater freedom from the surrounding parts, besides which it can
be more compactly folded up and stowed away.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is:
1. The jack or lifting mechanism for raising axles of heavy vehicles, motor
cars and other weights characterised by its having a loose head supporting stem,
provided with serrations or the like to facilitate holding, slidable up and down
in a hollow standard, a lever arm hinged to said standard and linked to a clutch
piece encircling and engaging the head supporting stem to lift and lower it and
a second clutch piece encircling and engaging the head supporting stem and
adapted to hold it in any position it is raised to whilst the first stem is being
released and reengaged, and a tripping or releasing arm mounted on the standard
for the purpose of tripping the second or holding clutch from its hold on the
step when the said head supporting stem is desired to be lowered, as set forth.
2. In a clutch of the construction described in Claim 1 the combination there-
with of a lever arm (as S) articulated so as to be capable of being locked in
working position or unlocked and folded close up against the body of the jack
as set forth.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicants.