Apparatus for treating dispersions and the like with non-sinusoidal vibration

Process and apparatus for treating material by applying non-sinusoidal vibrations. In apparatus for separating solids from the liquid phase of a dispersion, non-sinusoidal vibration is applied by vibrating at least a portion of a wall of a receptacle for the dispersion or by a vibrating plate, a pair of vibrating plates or a hollow body in the receptacle. In a roller mill for crushing material one of the rollers is vibrated axially relative to the other. In a juice press a vibrating plate is provided at the bottom of the press cylinder. In a jaw crusher, one of the jaws is vibrated in a direction parallel to the face of the jaw. In a ball mill comprising a cylinder rotating on a horizontal axis, the cylinder is vibrated in an axial direction. Non-sinusoidal vibration is produced by a hydraulic servomotor fed with pulses of hydraulic pressure fluid by a rotary control valve.

FIELD OF INVENTION 
The invention relates to a process and apparatus for treating solid and 
flowable material, in particular, flowable solid material mixtures and 
dispersions through vibrating implements. 
BACKGROUND OF INVENTION 
For years, vibrating implements have been employed to compact flowable 
solid material in the form of gravel, crushed rock, fresh concrete, and 
other building materials. The implements used produced a sinusoidal 
vibration capable of dispelling upwardly any air bubbles occurring in the 
material. However, any effect on the material itself was very limited. 
First, the use of the vibration as it can be produced, for example, 
through German patent specification No. 1957469, as well as through German 
patent No. 2213577, created the possibility of thoroughly working and 
thickening materials. The apparatus here disclosed was able to produce 
vibration which could then be applied to the material. A further 
possibility of treatment is disclosed in No. DE-OS2418858-7. In all cases, 
vibration could be produced through impulse-hydraulic-control-apparatus by 
means of hydraulic oil impulses and converted into mechanical impulses by 
means of a servo-motor in the form of a rotary motor and/or hydraulic 
cylinder piston unit. 
SUMMARY OF INVENTION 
The present invention is of particular significance for the treatment of 
flowable solid material mixtures, dispersions, and emulsions through 
vibrating implements. It has been determined through tests that the use of 
hydraulic impulses on flowable mixtures can lead to the separation and 
also to an intense homogenous mixing. Separation can be effected through 
the use of specific non-sinusoidal impulse forms of high frequency while a 
homogenous mixing can be obtained through the use of like implements with 
half or lower frequency. 
Various possibilities are known for separating specific heavy particles 
from lighter particles. The simplest, but also the oldest process, is 
separation by means of gravity in which a dispersion is allowed to stand 
in a basin or vessel whereby, through the lapse of time, more and more of 
the specific heavy parts collect on the bottom. In many branches of the 
technique, centrifuges are also used for this purpose. Instead of gravity, 
the centrifuge uses centrifugal force whereby the separation is achieved 
much more rapidly at the expense of using considerable energy. 
The separation of solid material from the liquid phase of a dispersion 
carried out on a very large scale, for example in filtration plants, paper 
factories, chemical processes, etc., is accompanied by considerable 
difficulty in that here the solid material must be separated from very 
large quantities of dispersion as quickly as possible, but with only a 
little energy, so that the installation is not too large. 
The separation of solids with different specific gravity gives rise in the 
technique to considerable difficulty which is greater when the specific 
gravities of the materials to be separated are near one another. In the 
dressing of ore-bearing stone from barren stone and after pulverizing the 
ore-bearing stone, it is difficult to separate the ore from the stone. It 
is likewise difficult to separate diamonds from fine-grain stone. Here the 
technique has contrived various processes of ore enrichment through 
flotation and other means which are expensive by reason of the machinery, 
energy, and labor required. 
The use of vibrating implements and machines is particularly popular where 
the tool works on the material without any counter tool. Stone drilling 
equipment is in most cases provided with an impact device which imparts a 
vibrating movement to the drill in the working direction. Compacting 
equipment is provided with vibrators vibrating in a sinusoidal mode in 
order to achieve a more efficient compacting with rollers and levelling 
plates, for example. In other fields of the technique, in particular where 
the tool is power driven relative to a counter tool, the technique does 
not use vibration but seeks to avoid vibration insofar as possible. Such 
vibration is to be prevented because self-excited vibration in such tools 
normally leads to rapid tool wear, and also to damage of the factory 
building, as well as to unpleasant working conditions. 
The applicant has found that in many work processes carried out by machines 
in which a tool is moved by power relative to a counter tool, improvement 
of the work process in the sense of a faster and more intensive working 
can be attained by imparting to the tool vibration which is not 
self-induced. 
The applicant has further recognized that in many work processes--the 
separation of a mixture of solids or of a dispersion of solids in liquid, 
for example--the separation can be considerably facilitated through the 
use of controlled pulse sequences of a particular kind. 
It is an object of the invention to provide a process and apparatus with 
which the processing intensity of material can be considerably increased 
and--in application to flowable mixtures--the parts of higher specific 
gravity can be separated relatively rapidly and with low energy 
consumption. 
The invention resides in that a series of non-sinusoidal impulses are 
applied to the work tool and/or counter tool, and that preferably during 
the process, the acceleration and/or the vibration frequency and/or the 
vibration amplitude is varied especially continually. 
In a series of applications, it is expedient if the work tool moves in one 
direction with a different acceleration than in the opposite direction. 
In this manner it is possible to attain astonishing results which otherwise 
can be attained only with a great expenditure of energy and through long 
treatment. If, for example, in machine tools, material is worked with a 
vibrating tool, the work is carried out more rapidly and with greater 
intensity through different acceleration peaks in the forward and back 
movement of the tool. If a solid body is worked by grinding and polishing 
tools which move back and forth, the working of the tool is intensified 
when it is moved forwardly with different acceleration peaks than in its 
backward movement. 
In particular, in the treatment and processing of flowable mixtures, 
whether of solids, liquids, or a solid-liquid mixture, astonishing results 
can be attained in this manner. Through vibration, especially in the range 
of 50 Hertz to 10,000 Hertz, an astonishingly fast agglomeration of the 
particles in suspension is obtained, which, when they are agglomerated to 
larger particles, sink rapidly to the bottom and remain there. For such 
vibration, relatively little energy is required--considerably less energy 
than, for example, in centrifuging which, with dispersions, often attains 
only moderate results. 
It is advantageous when, during the course of treatment, the acceleration, 
and/or the vibration frequency, and/or the vibration amplitude is varied. 
Through such variation, there is attained a particularly intense 
processing and treatment in that different size particles respond 
differently to variable frequencies and variable amplitudes. Through 
variation of the acceleration, vibration frequency and vibration amplitude 
ranges can be established in which the different material parts react with 
particular intensity. In particular, it is advantageous when the vibration 
frequency is repeatedly varied between two limits. It is particularly 
advantageous when the material is treated with a frequency spectrum, for 
example 50 to 160 Hertz, 150 to 450 Hertz, or the like. 
This process can be used in a wide variety of technical processes, for 
example, in filtration plants, settling tanks, sludge draining, paper 
manufacture, ore recovery, and similar areas where solids must be 
separated from liquids or from one another. It is also applicable, mostly 
with lower frequencies where materials are to be mixed, for example in the 
building material industry, abrasive wheel manufacture, and other branches 
of industry. 
An essential characteristic of the invention is that a controlled vibration 
movement is applied to the implement and/or the counter implement. In this 
manner, many operations can be carried out more intensively and faster. 
For example, in the pressing of plant or animal material, the vibratory 
movement can lead to a bettter disintregation and also to a thicker layer 
of the solid material. 
In particular, this is the case when the vibratory movement is transverse 
to the movement of the implement. For example, if a roller of a pair of 
rollers which crush the plant material is vibrated, there is produced 
during the pressing operation a pulverization of the plant parts that 
leads to a considerable improvement in the disintegration. If stone fruit 
such as plums, cherries, apricots and peaches, is pressed in a juice 
press, imparting a vibration movement leads to a considerable thicker 
layer of the solid material and thereby to a better pressing. 
In order to prevent such vibration being transmitted to the factory floor 
on which the machine is installed, it is desirable to impart vibration 
movement in opposite phase to the implement and counter implement. In like 
manner, vibration resonance is eliminated. 
It has been proved especially advantageous and efficacious when the 
vibratory movement is produced hydraulically by means of a servomotor 
acting on the tool or counter-tool and driven by hydraulic oil from a 
rotary valve which, in a constantly repeating sequence, rapidly connects 
the servomotor alternately with a source of hydraulic oil under pressure 
and with a return line. With this arrangement it is possible, through 
simply varying the speed of rotation of the rotary valve, to vary the 
frequency of the vibration to obtain an optimal value. At the same time, 
it facilitates in many cases finding the vibration best suited to the 
tool, the counter-tool, and the material being treated. 
As vibration is transmitted, in particular on the machine support, in an 
undesired manner when there is not sufficient material to be treated 
between the tool and counter-tool, and thus also when the machine runs 
empty or nearly empty, it is desirable to interrupt the vibration movement 
when the tool and counter-tool have moved toward one another so that there 
is a definite predetermined distance between them. 
The apparatus in accordance with the invention is characterized in that a 
hydraulic servomotor actuating the tool or counter-tool is driven by means 
of hydraulic oil from a rotary valve that connects the servomotor in a 
constantly repeating sequence alternately with a source of hydraulic oil 
under pressure and a return line, and that the rotary valve and/or its 
driving motor is provided with means whereby the frequency and/or 
amplitude may be varied by the moving part of the rotary valve and/or its 
driving motor. 
With this apparatus there is produced a series of non-sinusoidal impulses 
which lead to astonishing results in carrying out the work process. 
Through the non-sinusoidal pulses which are varied in their frequency, 
acceleration, or amplitude, the speed of the treatment is considerably 
increased and solid materials in a dry state can be separated from one 
another which could otherwise be separated only through troublesome 
chemical and/or flotation processes and similar physical procedures. It is 
not only the specific gravity which leads to the floating out of 
particular parts in a solid material mix during vibration, but also 
certain characteristics, e.g., different grain size and/or surface 
characteristics which lead to a separation under the influence of 
vibration. For example, particles with a very smooth surface may be 
separated from particles with a rough surface. 
An advantageous form of the apparatus is characterized by a hydraulic 
control valve of which a rotating axially moveable control cylinder is 
provided with annular grooves and branch channels having a component 
parallel to the axis. The branch channels communicate sequentially with 
conduits leading to the vibrating implement, while the annular grooves 
communicate respectively with ports in the housing connected with a 
hydraulic pressure line and a return line. Means are provided for driving 
the control cylinder in rotation at a variable speed, and for moving the 
control cylinder axially. 
This apparatus is easy and economical to produce. Its energy requirements 
are relatively low. 
In treating flowable materials, it is advantageous for the vibrating body 
to be a plate. However, it can be a pair of plates which are connected 
with one another through the vibrating means so that the two plates 
vibrate in opposite phase. The vibrating plate can also be a wall or part 
of a wall of the recepticle. Likewise, a vibrating rotary plate can be 
employed through which the space requirements are reduced. 
Suitably, the vibration driving means comprises a hydraulic cylinder-piston 
unit. A hydraulic vibration drive of this kind is capable of transmitting 
suitably strong vibrations to the fluid. Moreover, hydraulic vibration 
means of this kind is capable of transmitting vibrations of different 
frequencies, including high frequencies in the range of several 
kilo-Hertz. Besides the high power intensity of the hydraulics, the linear 
acceleration process operates advantageously. 
The vibrating member can also be a hollow body filled with hydraulic fluid 
which is set in vibration. 
The vibratory drive can advantageously be realized by connecting the 
hydraulic cylinder-piston unit or hollow body with a hydraulic control 
device which has a rotating or ocillating control cylinder by means of 
which the hydraulic cylinder or hollow body can be alternately connected 
with a hydraulic pressure line and a return line. Through this alternate 
connection with the pressure line and the return line strong impulses can 
be produced which are efficiently transmitted in the fluid. 
In the use of this apparatus in a settling tank, it is advantageous when at 
least one vertical plate is suspended in the fluid in the tank. In this 
manner, the solid material of a dispersion with a predominant liquid part 
can, with limited energy expenditure, be rapidly agglomerated so that it 
settles to the bottom of the receptacle. If two or more vibrating plates 
are employed in a settling tank, they are advantageously suspended in 
vertical alignment. 
From a dispersion with very high solid content which can be called swampy, 
liquid can be brought to the upper surface by means of a horizontal 
vibrating body which is preferably arranged at the bottom of the 
receptacle. The liquid thus separated is advantageously led to an adjacent 
receptacle where the sludge obtained is further dewatered. 
In this applicaation it is advantageous when nozzles are provided at the 
bottom of the receptacle for introducing air or oxygen whereby the 
vibrating plates can be apertured so that these nozzles can be arranged in 
or under the apertures. In this manner, the resulting sludge is already 
enriched with oxygen so that the decaying bacteria can already begin their 
activity. 
In the application of moving tools, in particular for machining and 
grinding, it is advantageous when a tool and counter-tool are energized 
with vibration of opposite phase so as to avoid transmission of vibrations 
to the machine support and factory floor. 
It has been found particularly advantageous when the vibrating movement is 
crosswise to the direction of movement of the tool. 
For the production of the vibration, it is advantageous to actuate the tool 
and/or counter-tool by a hydraulic servomotor which is supplied with 
hyraulic oil from a rotary valve which connects the servomotor in 
continually repeated sequence very rapidly, alternately with a hydraulic 
pressure line and a return line. 
In order to avoid premature tool wear or destruction and unnecessary 
transmission of vibration to the machine support and factory floor when 
the machine is running idle, it is advantageous to provide a control for 
the vibratory motor which switches off when the distance between the tool 
and counter-tool falls below a predetermined distance. Advantageously, the 
control device for this purpose can be provided with a pressure pick-up or 
with a motion pick-up.

DESCRIPTION OF PREFERRED EMBODIMENTS 
With reference to FIGS. 1 and 2, a tank or receptacle 1 contains a 
dispersion 2 in which a pair of plates 3 are suspended. The plates 3 are 
connected with one another by means of a hydraulic cylinder-piston unit 4. 
The plates 3 are suspended by means of supports 5 from a carriage 6 which 
runs on rails 6a at the sides of the receptacle. The carriage 6 is 
provided with means for raising the plates 3 so that they can be 
positioned at different heights and can be lifted completely out of the 
dispersion in the receptacle. 
A control device such as that shown in FIG. 5 or FIG. 6 is used to drive 
the hydraulic cylinder-piston unit 4 to vibrate the plates 3. This control 
device can advantageously be arranged on the carriage 6. If the plates 3 
were to be vibrated with conventional sinusoidal pulses, nothing would be 
altered in the dispersion. Only by activating the plates with 
non-sinusoidal pulses and, indeed, pulses in which the acceleration in one 
direction is greater than in the other direction, a rapid precipitation of 
the solid material is obtained when the frequency is continually varied 
within a predetermined range. 
In a filtration plant, the receptacles as illustrated in FIG. 1 are 
advantageously used for clarifying the dirty water from the sewer system. 
In FIG. 3 there is shown a receptacle in which a part of the bottom is 
formed as a vibrating body 7 which can also consist of plates but also can 
be a hollow body filled with hydraulic fluid. The receptacle of FIG. 3 is 
advantageously used in a sewage treatment plant to separate from the 
sludge, water which rises to the upper surface. A vibrating body such as 
the vibrating body 7 shown in FIG. 3 can additionally be used in the 
receptacle of FIG. 1 in order, alternately, first to clarify the dirty 
water, and then further to thicken the sludge whereby the sludge from one 
receptacle can advantageously be added to another receptacle. 
In the receptacle 1 of FIG. 4, a hollow body 8 is suspended from a carriage 
6 running on rails 6a at the side of the receptacle. The hollow body 8 is 
filled with hydraulic fluid 9 to which vibratory impulses are applied so 
that the walls of the hollow body 8 vibrate. There is thus assured good 
transmission between the vibrating hydraulic fluid in the hollow body 8 
and the fluid in the receptacle 1. At the bottom of the receptacle 1 there 
are provided nozzles 10 which are fed by conduits 11 and inject air or 
oxygen into the receptacle. Advantageously, the air or oxygen is not 
injected until a substantially thick layer of sludge has been formed over 
the nozzles because then the gas bubbles take effect better in the sludge 
and do not rise to the upper surface of the dispersion in the receptacle 
1. 
As in the embodiment of FIGS. 1 and 2, the hollow body 8 is suspended from 
the carriage 6 which is provided with means for raising or lowering the 
hollow body 8 so that it can be lifted out of the dispersion in the 
receptacle or at least is moveable to an edge of the receptacle in order 
to simplify emptying of the sludge. As illustrated in FIG. 5, the 
hydraulic cylinder 4 of the vibration unit in which a piston 14 is 
reciprocable--or the hollow body 8--is connected with the control unit 
through a conduit 12. An embodiment of the control unit as illustrated in 
FIG. 5 comprises a housing 15 in which a control rotor 16 is rotatable. 
Hydraulic oil from a storage tank 17 is delivered by a pump 18 through a 
conduit 19 to the housing 15 of the control unit. As the control piston 16 
has two grooves 16A and 16B, the conduit 12 leading to the hydraulic 
cylinder 4 or hollow body 8 is alternately connected with the pressure 
line 19 and with the return line 20 with a frequency depending on the 
speed of rotation of the control piston 16. 
In another embodiment illustrated in FIG. 6, a piston 22 having a radial 
channel 23 leading to a central channel 24 connected with the hydraulic 
cylinder 4 or hollow body 8 is rotatable in a housing 21. Here also 
pressure oil is supplied by a pump 18 to bores or grooves 25, 26 in the 
housing 21. Between each two bores or grooves 25, 26 there are two further 
bores 27, 28 connected with the return line 20 through an adjustable 
over-pressure valve 29. As the piston 22 rotates in the housing 21, the 
channel 23 communicates alternately with the oil pressure line through 
bores 25, 26 and the return line through bores 27, 28, thereby 
transmitting pressure pulses through the line 24 to the cylinder 4 or 
hollow body 8. It will be understood that bores connected with the 
pressure line, alternating with bores connected with the return line, can 
be provided throughout the inner circumference of the housing. Moreover, 
the circumferential extent of the bores and the distance between the bores 
are selected to provide the vibration characteristics desired. With this 
arrangement, pressure pulses are produced, the frequency and amplitude of 
which can be periodically varied. 
It will be understood that instead of rotating, the piston of the control 
device may be ocillated through a selected angle. 
In the treatment of sewage sludge with, for example, a frequency of 50 
Hertz, the plates have an amplitude of 3-4 mm, the acceleration peak value 
is 30 g and the back movement is about half that or less. An 
extraordinarily rapid separation of the solid particles from the liquid 
phase was achieved. 
The apparatus shown schematically in FIG. 7 comprises a hopper 31, at the 
lower end of which there is a pair of rollers 32, 33 which turn in 
opposite directions. They can be considered as tool and counter-tool 
respectively. At least one of the rollers 32, 33 is vibrated in an axial 
direction. For this purpose a hydraulic work cylinder 35 is provided 
between one end of the roller and its bearing 34 while between the other 
end of the roller and its respective bearing 34 a spring 36 is provided. 
The hydraulic cylinder 35 is fed over a conduit 37 from a rotary valve 38. 
The rotary valve 38 is fed through conduit 39 with a pressure source and 
further is connected with a return line 40 to return the hydraulic fluid 
to a storage tank from which hydraulic oil is supplied to the pressure 
source. As the rotary valve 38 rotates, pressure pulses are supplied 
intermittently to the hydraulic cylinder 35 to move the roller 33 
periodically toward the right as viewed in FIG. 8, return movement being 
effected by the spring 36. 
In the manner illustrated in FIG. 8 for roller 33, roller 32 can also be 
vibrated in an axial direction. Such vibration is likewise produced 
through a work cylinder 35 but is opposite in phase to the vibration of 
roller 33. For this purpose, the cylinder 35 for vibrating roller 32 is 
connected with the pressure source when the cylinder 35 of roller 33 is 
connected with the return line. 
Through the actuation of one roller 33 or both rollers 32, 33 with axial 
vibration, the material passing through the gap between the rollers is not 
only crushed and pressed but is also intensively rubbed and thereby 
disintegrated under pressure and torn apart. The superposed cross forces 
reduce the cylinder forces and thereby produce a finer material. 
To avoid the faces of the rollers being rubbed together by the axial 
vibration when the apparatus is running empty, there is provided a 
protective device which interrupts the vibration of the cylinders as soon 
as the machine is running empty. The bearing 34 of the roller 33 is 
moveable against the force of a spring 42 in a recess 43 of the machine 
frame 44. Between the spring 42 and the frame 44 there is provided a 
pressure measuring device 45 which measures the pressure of the spring 42 
on the machine frame 44. That is the pressure with which the rollers 32, 
33 are pressed together. This pressure increases the wider the rollers 32, 
33 are spread apart by the material passing between them. The pressure 
sensing device 45 is connected through a line 46 with a control device 47 
which is connected by a line 49 with a magnetic valve 48 in the pressure 
line that leads to the control valve 38. On the pressure between the 
rollers as sensed by the pressure senser 45 falling below a predetermined 
value, the magnetic valve 48 is closed so that the control valve 38 is no 
longer supplied with pressure fluid but is merely connected with the 
return line 40. Hence, the working cylinder 45 for vibrating the roller or 
rollers in an axial direction is no longer connected with the pressure 
line. Hence, axial movement of the roller 33, or also roller 35, occurs. 
This axial movement is resumed only when the gap between the rollers is 
increased by the material to be processed passing between the rollers so 
that the pressure in the pressure sensor 45 is again increased and the 
control device 47 opens the magnetic valve 48. 
Instead of the pressure sensor 45, there can be used a motion pick-up which 
measures the distance between bearings 34 of the rollers 32, 33 or 
measures directly the width of the gap between the rollers or the distance 
between the roller 32 and a reference point on the machine frame 44. 
As illustrated by way of example in FIGS. 9 and 10, the control device 38 
of FIG. 8 is constructed as follows: In a housing 50, a rotating cylinder 
51 driven by a variable speed motor M is axially displaceable and can be 
fixed in selected axial position. Through the conduit 39 oil under 
pressure is fed to port 39a in the housing 50 of the control valve. 
Through conduit 40 connected with ports 40a and 40b of the housing 50, oil 
is returned to the oil reservoir. The rotating cylinder 51 is provided on 
its periphery with annular grooves 52, 53 and 54 communicating 
respectively with ports 40a, 39a and 40b. From annular groove 52 
circumferentially spaced branch grooves 55 extend axially almost to 
annular groove 53. From annular groove 53 circumferentially spaced branch 
grooves 56 extend axially almost to annular groove 52 while 
circumferentially spaced branch grooves 57 extend axially almost to 
annular groove 54. From annular groove 54 circumferentially spaced branch 
grooves 58 extend axially almost to annular groove 53. The grooves 55 and 
56 are so arranged as to lie between one another. Likewise the grooves 57 
and 58 are so arranged that they lie between one another. In a 
circumferential direction, the branch grooves 56 and 57 are displaced 
circumferentially relative to one another. Grooves 56 are aligned axially 
with grooves 58 while grooves 57 are aligned axially with grooves 55. As 
seen in FIGS. 9 and 10, the branch grooves 55 to 58 are tapered in an 
axial direction. 
Oil under pressure is fed to annular groove 53 through conduit 39 and port 
39a and flows into branch grooves 56 and 57. Annular grooves 52 and 54, 
together with their branch grooves 55 and 58, respectively, are in 
communication with the oil return line 40 through ports 40a and 40b, 
respectively. The housing 50 is further provided with a port 37a connected 
by a line 37 with work cylinder 35 of roller 33 and with a port 41a 
connected by line 41 with the work cylinder 35 of the other roller 32. 
Port 37a is positioned to communicate alternately with branch grooves 55 
and 56 as the cylinder 51 rotates, while port 41a is positioned to 
communicate alternately with branch grooves 57 and 58. 
Through this arrangement, the following occurs: As the cylinder 51 rotates, 
the port 37a communicates alternately with branch grooves 56 and branch 
grooves 55. When the port 37a is in communication with branch grooves 56, 
oil under pressure is fed from circumferential groove 53 to line 37 for 
very short intervals of time. In between these intervals, line 37 is 
connected with the return line 40 through branch grooves 55 and 
circumferential groove 52. Thus, as the cylinder 51 constantly rotates, 
line 37 is connected alternately with pressure line 39 and return line 40 
in continual sequence. The speed of rotation of the cylinder 51 determines 
the frequency of the oil pressure pulses supplied intermittently from oil 
pressure line 39 to line 37. 
The same thing happens with respect to branch grooves 57 and 58 through 
which line 41 is alternately connected with pressure line 39 and return 
line 40 in continual sequence. However, this is out of phase with respect 
to line 37, since branch grooves 57 are circumferentially offset relative 
to branch grooves 56. As the branch grooves 55 to 58 are suitably tapered 
toward their outer ends, a variation of the length of the hydraulic 
impulses can be effected by displacing the cylinder 51 axially whereby the 
intervals of time that lines 37 and 41 are connected with pressure line 39 
and return line 40 can be varied. 
The frequency of the vibration produced is regulated by controlling the 
speed of the motor M. The amplitude and acceleration can be selected by 
the hydraulic oil pressure, the cross sectional area of the 
cylinder-piston unit, the cross section of the connecting lines and the 
flow-through opening of the control valve. 
The hydraulic cylinder 35 illustrated in FIG. 8 has oil pressure applied 
intermittently to only one side of its piston. It is hence necessary to 
provide the spring 36 to move the roller in the opposite direction. 
However, a double-acting hydraulic cylinder can be used with oil pressure 
applied alternately to opposite sides of the piston. In this event, one 
end of the hydraulic cylinder is connected with line 37, while the other 
end of the hydraulic cylinder is connected with line 41 of FIG. 9. 
The press shown in FIG. 11 is for pressing juice out of fruit. In a 
cylinder 59 to be filled with the fruit, a piston 60 is movable in known 
manner either through a hydraulic cylinder or a threaded spindle 61 or 
other means in a direction toward the bottom of the cylindrical container 
59 which is provided with openings for discharge of the fruit juice. On 
the bottom of the container, there is a vibrator which is shown more fully 
in FIG. 12. The vibrator comprises two discs 62, 63 which face one another 
and are moveable relative to one another in the plane of their faces by 
means of a piston 64. The piston 64 is connected by piston rod 65 with 
disc 62 and is moveable axially in a hydraulic cylinder 66 which is 
located between the discs and is fixed to disc 63. Opposite end portions 
of the cylinder 66 are connected by lines 37 and 41 respectively with the 
control valve 38 shown in FIG. 9. With this vibrator, vibrations are 
produced at the bottom of the cylindrical container 59 in a direction 
transverse to the direction of movement of the piston 60. Such vibrations 
are transmitted to the material being processed in the container 59 and 
lead to particularly efficient and rapid pressing out of the juice as the 
solid material is compacted at the bottom of the container. 
FIG. 13 illustrates a jaw-breaker in which a moveable jaw 69 pivotally 
supported by a shaft 68 in the frame 67 is moveable toward the jaw 72 by 
means of a hydraulic cylinder-piston unit 70 of which the piston rod is 
connected with toggle linkage 71. The jaw 72 comprises a plate which is 
displaceable in a direction parallel to its outer face by means of a 
piston 64 reciprocable in a hydraulic cylinder 66 and connected to the 
plate 72 by piston rods 65. Opposite end portions of the cylinder 66 are 
connected respectively by lines 37 and 41 with the control valve 38 shown 
in FIG. 9. The plate form jaw 72 serving as the counter-tool is supported 
in the machine frame 67 by slide rails 74. Through the vibration of the 
plate form counter-jaw 72, the breaking of the stone is effected more 
rapidly and with less force by reason of the constant small alternation of 
the angle of attack of the forces exerted by the moveable jaw 69. It will 
be seen that the vibratory movement of the counter-jaw 72 is transverse to 
the direction of movement of the jaw 69. 
In FIG. 14, there is shown a ball mill in which a cylinder 75 is rotatably 
supported on a frame 76 by a shaft 90 driven by conventional means. The 
container 75 is vibrated in an axial direction by cooperation of a 
hydraulic work cylinder 35 which moves the container axially in one 
direction and a return spring 36. It will be understood that instead of 
the return spring 36, the hydraulic cylinder 35 can be made double-acting 
or a hydraulic cylinder can be provided at each end of the container 75. 
By reason of this vibration, there occurs not only a working of the 
material in the container through the impact of the falling balls, but at 
the same time there is a rubbing action between the container 75 and the 
balls at the bottom of the container. By reason of the axial forces acting 
to vibrate the container, the mill bodies inside the container 75 are also 
vibrated. Through this action, a more rapid milling of the material in the 
container is obtained. 
It will be realized that there are many more possible applications of the 
invention to a wide variety of machines and apparatus. 
Thus, for example, the invention is advantageously applied to ore 
preparation. Crushed ore is processed first in a jaw-breaker, as 
illustrated in FIG. 13, and then in a roller mill, as illustrated in FIGS. 
7 and 8, to reduce it to grain size. The granulated material is then 
charged into the hopper 77 of the solid material separating apparatus 
illustrated schematically in FIG. 15. From the hopper 77, this mixture of 
granulated solid material flows first along a conveyor 79 of U-shaped 
cross-section with an inclined floor 78 supported by two pivoted links 80. 
A vibration movement with unequal forward and return movement is imparted 
to the conveyer 79 by a cylinder-piston unit 81. From the conveyer 79 the 
granulated ore falls into a second vibrating conveyer 82 which is 
supported by links 83 and is vibrated by a cylinder-piston unit 84. At the 
end of the conveyer 82 there is a stationary wall 85 with a lower 
discharge chute 86 out of which the heavier ore falls into a dump cart 87, 
as well as with an upper discharge chute 88 out of which the lighter 
barren stone falls into a dump cart 89. 
While preferred embodiments of the invention have been illustrated in the 
drawings and are herein particularly described, it will be understood that 
the invention has still other applications and is in no way limited to the 
illustrated embodiments.