Improvements in or relating to Hydraulic Brake Apparatus for Vehicles and other purposes.
Year: 1895

page_text: Date of Application, 8th Nov., 1895
Complete Specification Left, 7th Sept., 1896-Accepted, 7th Nov., 1896
PROVISIONAL SPECIFICATION.
Improvements in or relating to Hydraulic Brake Apparatus for
Vehicles and other purposes.
I, RAYMOND SNYERS, of 76 Rue Mercelis, Brussels, Civil Engineer, do hereby
declare the nature of this invention to be as follows:-
This invention has reference to improved constructions and arrangements of
hydraulic apparatus for use in conjunction with brakes of various kinds such as
elastic brakes of the kind described in the Specification of former Letters Patent
granted to me No. 11337 of 1887, friction-brakes, such as shoe brakes, band brakes,
multiple disc brakes, and others, and which are capable of being operated by hand or
foot, or by mechanical means.
The hydraulic brake apparatus, whatever may be its manner of application,
comprises two main parts or devices viz.: an operating device upon which the hand,
foot, or power mechanism acts to produce hydraulic pressure, and a compressor which
receives the said pressure and actuates in a direct manner the brake proper, these
two devices being simply connected with each other by means of a small tube, herein-
after called the transmission tube.
In one construction of iny apparatus, the compressor comprises a dish-shapeḍ
vessel having a properly machined or surfaced seat against which bears a corrugated
diaphragm that forms one side of a pressure chamber, such diaphragm, which is made
of elastic or flexible material, as for example india-rubber or leather, being secured
tightly upon its seat by means of a screw-threaded ring. At the outer side of the
diaphragm, is a sheet metal disc carrying a pin at its centre, the arrangement being
such that on liquid pressure being produced within the said pressure chamber, the
diaphragm bulges outward and forces out the aforesaid disc and also the pin, which
may act after the manner of a piston or pusher to operate the brake proper. The
pressure chamber is provided with an orifice to which is connected a pipe leading
to the operating device and also, it may be, with another orifice which serves for the
exit of air when priming or charging the apparatus with liquid.
The return of the diaphragm to its normal position, when the pressure is removed,
is effected, either by reason of its elasticity alone, or by the aid of a spring provided
in the compressor or in the operating device. The form of the operating device
may vary according to the use for which the brake is designed. In applying a
compressor of the kind just described to a Snyer's elastic brake, the end ways movable
brake disc carrying the elastic plates is fixed directly to the pin attached to the
diaphragm of the compressor and the dish-shaped pressure chamber is provided with
guides in which projections on the said brake disc work in such a manner that the
said disc is guided in its movement in a straight line in the direction of its axis, and
is at the same time prevented from being carried around by the rotation of the
toothed disc fixed to the wheel to which the brake apparatus is applied.
In another application, the pin attached to the diaphragm of the compressor is
connected to a brake shoe or block suspended from a bracket carried by the.
compressor, the arrangement being such that the bulging out of the diaphragm has
for result to force the brake shoe or block against the periphery of the wheel to
which the apparatus is applied.
In another application the diaphragm directly operates by means of a bell crank.
lever. a brake band extending round a pulley keyed on the axle of a vehicle or

page_text: on the shaft of a machine or engine, the arrangement being such that the outward
movement of the diaphragm acts to tighten the band upon the pulley.
In another construction of my apparatus applicable to wheels or pulleys, the
⚫compressor comprises one or more tubes of flattened form in cross section similar
to Bourdon-pressure gauge tubes, these tubes being bent to a circular form,
arranged concentrically to each other when there are two or more, and placed
within the rim of the wheel or pulley to be braked. The tube, or each tube, is
fastened at one end to a fixed point by means of a hollow axle, which also serves as
a union or connection for the pipe communicating with the aforesaid operating device,
so that upon being subjected to internal pressure, the tube or tubes will as well
understood, tend to straighten that is to say will increase its, or their radius of
curvature and by this means will be caused to bear against the inner surface of the
wheel or pulley so as to act as a brake thereto.
The bent flattened tubes may also be arranged around the exterior of the wheel or
pulley, but in this case the operation is the reverse of that just described, that is to
say, normally there should be constant fluid pressure in the tubes so as to hold them
out of contact with the rim of the pulley, and the brake is applied by releasing this
pressure. The tubes then close on to the pulley by reason of their elasticity, aided it
may be by the action of a spring or springs.
In a modified arrangement, there is arranged inside a pulley, a circularly bent
tube of oval form in cross section, held in the groove or channel of a fixed ring, to
which is also fixed a brake band encircling the bent tube. This tube is in communi-
cation with the aforesaid operating device so that upon being subjected to internal
pressure it will assume a rounder form in cross section, and in so doing will expand
and force the brake band against the inner surface of the pulley rim, thereby putting
the brake in action.
In each arrangement in which a bent tube or tubes is or are placed within the
pulley, when the internal pressure ceases, the action of the brake ceases at the same
time, the tube or tubes reassuming its or their initial condition by reason of their
elasticity.
An arrangement of brake apparatus for use with a road carriage, is as follows:-
To the nave or hub of one of the wheels of the carriage is keyed a pulley inside
which are arranged a number of circularly bent flattened tubes arranged concen-
trically with each other and each fixed at one end to a sleeve or collar secured to
the axle of the wheel. The outer tube is provided with material such as leather
or wood to take friction, and which can be readily renewed. The tubes are in
communication with the operating device by means of a pipe which can be easily
arranged alongside the carriage body so as to be hidden from view in order that
it may not spoil the appearance of the carriage. The operating device, which is
or may be placed under the coachman's box or seat, may consist in this case, of a
bellows of suitable material, for example leather or india rubber, arranged within
a metal or other suitable casing and connected to a piston or plunger adapted to
be operated by a treadle lever, the arrangement being such that by depressing the
treadle lever and thereby compressing the bellows liquid will be forced into the
aforesaid bent tubes and the brake applied.
Brake apparatus of the kinds hereinbefore described are specially suitable for use
with cycles and like vehicles. In one arrangement for this purpose, the compressor
is of the kind first herein described and comprises a dish-shaped vessel fixed to the
frame of the bicycle by means of lugs and a diaphragm arranged to operate a
fork which is pivoted at one end upon a bracket cast in one with the said vessel,
and has its two limbs, which are adapted to bear against the tyre of one of the
wheels of the vehicle, enclosed in a sheath of material such as leather or india-
rubber. In place of a fork, the diaphragm may be arranged to operate a brake shoe
or block.
In another arrangement suitable for a cycle or like vehicle the compressor is a
circularly bent flattened tube of the kind hereinbefore mentioned arranged within a
pulley keyed on the axle of one of the wheels of the vehicle, the said tube being

page_text: attached at one end to the frame of the bicycle (when the brake is to be applied
to the hind wheel), or to the steering fork, (when it is to be applied to the front
wheel).
The operating device for each of these cycle arrangements, consists simply of a
small ball or pear of india rubber mounted on one end of the transmission tube
which is connected with the compressor and which is fixed on the handle bar by
means of a clip. For priming or charging the apparatus with liquid, the said
transmission tube is provided with two branches through one of which the air
contained in the apparatus can be drawn whilst liquid is allowed to enter by the
other. When this means of priming is adopted, the aforesaid orifice in the dish-
shaped vessel of the compressor may be dispensed with. The transmission tube is
conducted along the frame of the cycle and may, if desired, be placed inside the
tubes of the frame so as to be hidden from view.
When it is desirable to develop a greater braking action than can be produced by
the direct application of hand pressure to the ball or pear, a spring claniping device
or vice may be provided that is fixed to the handle-bar of the cycle and within
which the india rubber ball or pear can be compressed by one of the jaws of the
said device which is made as a lever.
The liquid employed to charge the apparatus may be of various kinds but a mixture
of water and glycerine is preferred..
Improvements in or relating to Hydraulic Brake Apparatus for
Vehicles and other purposes.
I, RAYMOND SNYERS, of 76 Rue Mercelis, Brussels, Civil 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:
This invention has reference to improved constructions and arrangements of
hydraulic apparatus which are suitable for use in conjunction with brakes of various
kinds such as elastic brakes of the kind described in the Specification of former
Letters Patent granted to me and numbered 11,337 of 1887, friction-brakes, including
shoe-brakes, hand-brakes, multiple-disc brakes, and others, and which are capable of
being operated by hand or foot or by mechanical means.
The hydraulic brake-apparatus, whatever may be its manner of application,
comprises two main parts or devices, viz. an operating-device upon which the band,
foot, or power-mechanism acts to produce hydraulic pressure, and a compressor or
receiver (hereinafter called a receiver) which receives the said pressure and actuates,
in a direct manner, the brake-shoe or its equivalent, the two devices being
simply connected with each other by means of a small tube, hereinafter called the
transmission-tube.
Figs. 1 and 2 of the accompanying drawings are respectively side and end
elevations, the latter, partly in section illustrating one construction of brake-apparatus
according to this invention. The receiver, which is shown separately, in its expanded
state, half in section and half in elevation in Fig. 3, comprises a dish-shaped plate 1
and a corrugated diaphragm 2 that forms with the plate 1 a pressure-chamber 3, such
diaphragm, which is made of flexible material (as, for example, india rubber or
leather) being secured tightly on the plate 1 by means of a ring 4 and set-screws 5.
To the outer side of the diaphragm 2 is fixed a sheet-metal disc 6 to which un

page_text: operating cross-piece 7 is secured, the arrangement being such that on liquid-
pressure being produced within the pressure-chamber 3, the diaphragm 2 will
bulge outward and force out the disc 6 and also the operating cross-piece 7,
which may act after the manner of a piston or a pusher (as shown) to operate
the brake-shoe or equivalent device. The pressure-chamber 3 is provided with a
pipe 8 to which is connected a pipe 9 leading to the operating-device 10 and
also, it may be, with another pipe at 11 (normally closed by, a screw stopper 12)
which serves for the exit of air when priming or charging the apparatus with
liquid. The pipes 8 and 11 may couveniently be formed, as shown, by hollow
bolts that also serve to secure the operating cross-piece 7 and dise 6 to the
diaphragm 2. As shown in Figs. 1 and 2, the cross piece 7 operates the brake-
shoe or equivalent device by means of a forked lever 13, which is journalled
at 14 in an extension 15 of the plate 1. The return of the diaphragm 2 to its
normal position, when the pressure is removed, may be effected by the aid of a
spring provided in the receiver or in the operating-device; but it is preferred in
the construction referred to to use for this purpose rubber springs 16, which pass
around projections 17 of the plate 1 and also around the lever 13.
The lever 13 may be varied in form according to circumstances and may be
arranged to operate brakes of various kinds. In the case of a cycle it is preferable to
employ a roller-brake such as shown in Figs. 1 and 2, but the particular construction
of which is not herein claimed as forming part of the present invention. In this case
the lever 13 has secured to it at the end away from the receiver, by means of a
pin 18 of square section, two conical axles or supports 19, which are of large
diameter and on which are mounted, so as to be readily rotatable thereon, two
rollers 20) covered outside with india-rubber 21. The conical supports 19 are each
provided with a pocket 22 into which can be put a lubricant or other substance either
to increase or to diminish the adherence between the conical rollers 20 and their
supports 19. The diameter of the axles or supports 19 and the external diameters.
of the rollers 20 are so chosen, in view of the co-efficients of friction between
the axles or supports-19 and the rollers and between the rollers and the tyre 23, that
all sliding of the tyre 23 on the rollers 20. will be obviated, and consequently also all
wearing of the tyre by the brake-rollers. It will be seen that the arrangement of
this apparatus is such that the rolling resistance of the rollers will be increased
proportionally to the pressure exerted on the tyre. 24 are rubber flaps that act as
scrapers to remove mud from the rollers. The receiver is secured in position on a
cycle by means of hooks 25 which are fastened by nuts 26 to a projection 27 of the
plate and are caused to engage with the tubes 28 (see Fig. 4) of the frame of the
cycle.
In lieu of securing the receiver to the lower tubes 28 as just described, it may be
secured, as shown in Fig. 4, to the saddle pillar tube 29 of a bicycle. In this case, as
shown in plan in Fig. 5, the projections 27 of the plate 1 have rigidly attached to
them two screwed rods 30 carrying cross-pieces 31, which are clamped by means of
nuts 32 on the tube 29.
Fig. 6 is an elevation representing a modification in which the receiver is secured
to the tube 29 as just described but the lever 13, instead of carrying a pair of rollers,
carries two rubber shoes 33, which rub on the outer periphery of the tyre but may be
arranged to rub on the inner periphery of the felloe of the wheel in which case
the receiver 3, and lever 13 would be reversed in position so that the lever would be
moved away from the wheel felloe instead of towards it when the receiver were
expanded.
In another application, shown in Fig. 7, the diaphragm 2 directly operates by
means of a bell-crank lever, a brake-band 34 extending round a pulley 35 koyed on
the axle of a vehicle or on the shaft of a machine or engine. The said bell-crank lever
has three arms, of which one, 26, is attached to the operating cross-piece 7 and the
two others, 37 and 38, are attached to the two ends of the band 34, the arrangement
being such that the outward movement of the diaphragın 2 acts to tighten the band 34
upon the pulley 35.

page_text: The diaphragm instead of being of bellows shape as shown in Figs. 1 and 3, may
consist as shown in Fig. 34, of a flat disc of india rubber or leather so moulded or
pressed to shape as to form one or more corrugations or ridges 2 of annular shape in
face view and of vee shape in cross section, the edge of the disc being clamped to a
plate such as 1 (Figs. 1 & 3) to which the transmission tube is connected. Plates 6
and 7 cover the two sides of the diaphragm and carry a pin 7* that serves to transmit
the motion of the diaphragm to the brake to be operated.
The operating-device for each of the cycle arrangements may consist, as shown in
Fig. 2, simply of a small ball or pear 10 of india rubber, which is mounted on one
end of the transmission-tube 9 and which may be fixed on the handle-bar by means
of a clip. The transmission-tube is conducted along the frame of the cycle,
and may, if desired, be placed inside the tubes of the frame so as to be hidden
from view.
When it is desirable to develop a greater braking action than can be produced
by the direct application of hand-pressure to the ball or pear, a spring clamping
device or vice 39 (Fig. 8) may be provided, which may be fixed by a bracket 40
to the handle-bar 41 of the cycle and within which the india-rubber ball or
pear 10 can be compressed by one of the jaws of the said device, which is
adapted, as shown, to act as a lever. Fig. 9 represents a modification of this
arrangement in which the operating-device consists of a bellows 42, which is provided
with a steel end plate 43 adapted to be secured to the handle bar of a cycle
by means of a clamp 44 and is adapted to be compressed by means of a lever 45
connected to it at 46 and pivoted at 47 to an extension 48 of one portion of the
clamp 44.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is -
=
1. The construction and application of hydraulic brakes for cycles and like vehicles
substantially as herein described.
2. Brake-apparatus constructed, arranged, and operating substantially as herein-
before described with reference to the several examples illustrated in the accompanying
drawings
Dated this 7th day of September 1896.
For the Applicant,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.