Abstrict An angle .theta. formed between a horizontal line passing through
the contact point P and a slant surface of a mantle based on an
empirical rule corresponding to the vertical distance L ranging
from the reference line S to the contact point P of the mantle continued
to vary due to abrasion is inputted in advance into an angle inputting
and outputting device, the angle .theta. corresponding to the vertical
distance L detected by a distance sensing device in reference to
an angle inputted value is selected and at the same time the selected
angle is inputted into the distance calculating device, a product
of a distance difference .DELTA.L between the contact point P of
the concave and the contact point P of the mantle and a cosine value
of the angle .theta. is calculated by the distance calculating device,
resulting in that an inputting operation for the angle .theta. can
be eliminated, so that a stop time of the cone crusher is reduced
and an operating efficiency of the cone crusher is improved.
Claims What is claimed is:
1. A method for determining an outlet clearance of a cone crusher
comprising the steps of:
sensing a first distance between a contact point and a reference
position under a condition in which a concave and a mantle are contacted
to each other;
sensing a second distance between said contact point and said reference
position under a condition in which the concave and the mantle are
spaced apart from each other;
calculating a difference between said first distance and said second
distance; and
selecting an empirically determined angle between a horizontal
line passing through said contact point and a slant surface of the
concave or the mantle as a function of a vertical distance between
the contact point and the reference position; and
determining the outlet clearance based upon the selected angle.
2. A method for sensing an outlet clearance of a cone crusher according
to claim 1 wherein said concave is movable.
3. A method for sensing an outlet clearance of a cone crusher according
to claim 1 wherein said mantle is movable.
4. A method for sensing an outlet clearance of a cone crusher according
to claim 1 wherein setting said angle corresponding to said vertical
distance is carried out by linear interpolation using data of angles
at a plurality of predetermined vertical distances.
5. A method for sensing an outlet clearance of a cone crusher according
to claim 1 wherein setting said angle corresponding to said vertical
distance is carried out on basis of a functional equation of a predetermined
vertical distance and said angle.
6. A method for sensing an outlet clearance of a cone crusher according
to claim 1 wherein said step of determining the outlet clearance
based upon the selected angle comprises calculating a product of
a cosine value of the selected angle.
Description BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method for sensing an outlet clearance
of a cone crusher for use in crushing ores or rocks and the like.
2. Description of the Related Art
A cone crusher is comprised of a concave and a mantle fitted outwardly
at a cone segment formed at an upper portion of a main shaft, said
main shaft being rotatably arranged in a vertical orientation at
a central part of the concave in its diametrical direction, wherein
ores or rocks and the like are crushed between the concave and the
mantle. As such a cone crusher, there are two types of crushers,
one in which the concave is moved up and down in order to adjust
an amount of abrasion and the other in which the mantle is moved
up and down to adjust an amount of abrasion. In such cone crushers
as described above, it is necessary to keep a particle size of ores
or rocks and the like within a predetermined range and it is an
essential requirement to keep a constant clearance between the concave
and a part near an outer periphery of the mantle, i.e. a constant
outlet clearance.
Due to this fact, although it is necessary to detect the outlet
clearance, the cone crusher 1 in which the concave 2 is moved up
and down is constructed such that as shown in FIG. 4 the concave
2 is threadably fitted to a concave support 1a, resulting in that
an amount of rotation of the concave support 1a is detected by a
proximity detector and the like to calculate a distance La between
a reference position S and a contact point Pa in the mantle 3 and
to calculate a distance Lb between the reference position S and
a contact point Pb in the concave 2 and then a difference .DELTA.L
of distances in a vertical direction between the contact point Pa
of the mantle 3 and the contact point Pb of the concave 2 is calculated
in reference to these distances, .DELTA.L.times.cos.theta. is calculated
in reference to .DELTA.L and an angle .theta. formed between a horizontal
line passing through the contact point Pa of the mantle 3 and a
slant surface of the mantle 3 and then an outlet clearance G between
the cone cape and the mantle 3 is calculated.
In another cone crusher in which the mantle is moved up and down
as shown in FIG. 5 a differential transformer or a magnetostriction
displacement meter or the like is used for calculating the distance
La between the reference position S and the contact point Pa of
the concave 2 calculating the distance Lb between the reference
position S and the contact point Pb of the mantle 3 measuring a
difference .DELTA.L of distance in a vertical direction between
the contact points Pa, Pb of the concave 2 or the mantle 3 in reference
to these values, and then a product of .DELTA.L.times.cos.theta.
of the difference .DELTA.L and a cosine of the angle .theta. between
the horizontal line passing through the contact point Pb of the
mantle 3 is calculated by a clearance calculating device so as to
get the outlet clearance G between the cone cape 2 and the part
near the outer periphery of the mantle 3.
Since the angle .theta. is varied due to abrasion between the concave
and the mantle and the angle .theta. is gradually decreased as the
abrasion grows, the calculated values are gradually spaced apart
from the actual outlet clearance G. Due to this fact, in the prior
art, the angle .theta. was corrected in response to a difference
L at the inputting and outputting device every time the abrasion
at the concave or the mantle is progressed and then the corrected
angle .theta. was inputted to calculate the outlet clearance G.
The number of inputting works of the angle .theta. carried out until
the cone cape or the mantle is replaced with a new one is normally
about 30 times in the case that the items to be crushed are rocks.
However, when the inputting work of the angle .theta. was carried
out, the operation of the cone crusher had to be stopped to carry
out an actual-measuring work for the minimum outlet clearance, resulting
in that the operation was not only a quite troublesome work but
also caused trouble in improving an operating efficiency of the
cone crusher.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method for
sensing an outlet clearance of a cone crusher in which an inputting
work for the angle .theta. is not necessary.
The preferred embodiment of the present invention is carried out
such that a first distance between the contact point and the reference
position is detected at a condition in which the concave and the
mantle are contacted to each other; a second distance between a
contact point where one of the concave and the mantle is moved and
the reference position is detected at a condition in which the concave
and the mantle are spaced apart; a difference between the first
distance and the second distance is calculated; and a product of
a cosine value of an angle which is varied in response to a vertical
distance between the contact point where one of the cone cape or
the mantle is not moved and an angle formed between the horizontal
line passing through the contact point and a slant surface of the
cone cape or the mantle and the difference is calculated to detect
the outlet clearance.
Accordingly, even if the abrasion of the concave or the mantle
is progressed being different from the prior art, the actual outlet
clearance and the outlet clearance calculated by the clearance calculating
device is not different. As a result, the inputting work of the
corrected angle .theta. can be eliminated and an operating efficiency
of the cone crusher is increased.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a schematic view for showing a main portion to indicate
a positional relation between the concave and the mantle at an initial
condition of the cone crusher in the first preferred embodiment
of the present invention;
FIG. 1B is a schematic view for showing the main portion in the
first preferred embodiment of the present invention to indicate
the case in which abrasion is progressed to be the maximum distance
between the reference position and the mantle in a vertical direction;
FIG. 1C is a relative illustration of an angle .theta. corresponding
to the distance L between the reference position and the contact
point P of the mantle varied due to its abrasion;
FIG. 2 is a relative illustration of an angle .theta. corresponding
to the distance L between the reference position and the contact
point P of the mantle varied due to its abrasion in the second preferred
embodiment of the present invention;
FIG. 3 is a schematic illustration to show a main portion in the
third preferred embodiment of the present invention;
FIG. 4 is a schematic illustration to show a main portion in the
cone crusher in the prior art; and
FIG. 5 is a schematic illustration to show a major part in the
cone crusher in the prior art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention has been completed in View of the fact that
abrasion condition between the concave and the mantle is kept constant
from time of new one to replacing time and a varying state of the
angle .theta. caused by abrasion is not changed if physical properties
of rocks and particle size of supplied raw rocks are kept constant
and a load of the cone crusher is not substantially changed, and
under such a condition as above, if a plurality of angles .theta.
n (n=1 2 3 . . . n) corresponding to a vertical distance L between
the reference position varying by abrasion and the contact point
P on one of the concave or the mantle which is not moved are inputted
again to an inputting or outputting device, an angle .theta. corresponding
to the vertical distance L detected by the distance sensing device
is selected from the inputted angles .theta. n, and thereby the
outlet clearance G is calculated to eliminate the inputting work
for the angle .theta..
The method for sensing an outlet clearance of a cone crusher of
the first preferred embodiment of the present invention will be
described in reference to FIG. 1A for showing a positional relationship
between the concave and the mantle under initial condition, FIG.
1B for showing a case in which abrasion is progressed and the maximum
distance is produced in a vertical direction between the reference
position and the mantle, and FIG. 1C for illustrating a relation
of the angle .theta. corresponding to the distance L between the
reference position and the contact point P of the mantle varied
by abrasion.
That is, reference numeral 1 shown in FIG. 1A and FIG. 1B denotes
a cone crusher, wherein a concave 2 of the cone crusher 1 is threadably
fixed to a screw (not shown) arranged inside a concave support 1a
in such a way that the concave can be moved up and down. Then, a
mantle 3 is mounted at a lower position spaced apart by an outlet
clearance G in respect to the lower side of the concave 2.
An angle .theta..sub.0 between a slant surface of the mantle 3
and the horizontal line for calculating the outlet clearance G at
an initial stage of the cone crusher 1 having such a configuration
as above is calculated as an angle at a position of the contact
point Pa when the concave 2 is moved down and contacted with the
mantle 3. Then, the concave 2 is lifted up until the outlet clearance
G becomes a predetermined value.
When a proper outlet clearance G is formed between the concave
2 and the mantle 3 under the lifting-up operation of the concave
2 the items to be crushed can be crushed, although abrasion of
the concave 2 and the mantle 3 are progressed as the operation is
continued to cause the angle .theta. to be varied, so that when
the outlet clearance G after abrasion is calculated on the basis
of the angle .theta..sub.0 calculated under an initial setting,
the calculated outlet clearance G is gradually spaced apart from
the actual outlet clearance to cause an inaccurate value to be attained.
However, in the preferred embodiment, as shown in FIG. 1C, the angles
.theta..sub.0 .theta..sub.1 .theta..sub.2 .theta..sub.3 . . .
, .theta..sub.max based on an empirical rule corresponding to the
vertical distances L.sub.0 L.sub.1 L.sub.2 L.sub.3 . . . , L.sub.max
ranging from the reference position S to the contact point Pa of
the mantle 3 which continues to vary by abrasion are inputted in
advance into an angle inputting or outputting device (not shown).
Although the aforesaid vertical distances L.sub.0 L.sub.1 L.sub.2
L.sub.3 . . . L.sub.max and the distance Lb between the reference
position S and the concave 2 are detected together by a distance
sensing device (not shown), each of the distances detected by the
distance Sensing device is inputted into the clearance calculating
device (not shown), and then a difference .DELTA.L is calculated
by the clearance calculating device.
In addition, in concurrent with this operation, an angle .theta.
corresponding to the vertical distance L, between the reference
position S detected by the distance sensing device and the contact
point Pa of the mantle 3 varying due to wear is selected from angles
.theta..sub.0 .theta..sub.1 .theta..sub.2 .theta..sub.3 . . .
, .theta..sub.max, the selected angle .theta. is inputted into the
clearance calculating device and at the same time the outlet clearance
G is calculated in reference to a product of the aforesaid difference
.DELTA.L and a cosine of the selected angle .theta., i.e. .DELTA.L
.times.cos.theta. is calculated by the clearance calculating device.
As described above, the outlet clearance G is calculated in reference
to the angles .theta..sub.0 .theta..sub.1 .theta..sub.2 .theta..sub.3
. . . , .theta..sub.max based on an empirical rule, so that the
actual outlet clearance and the outlet clearance got through calculation
are not spaced apart wide as found in the prior art, resulting in
that an inputting work for the angle .theta. acting to require a
substantial work can be eliminated and then an operating ratio of
the cone crusher can be substantially increased.
In addition, the angle .theta. in the case that the vertical distance
L between the reference position S detected by the distance sensing
device and the contact point P of the mantle 3 varying by abrasion
is set between L.sub.4 and L.sub.5 for example, and the the angle
.theta. s corresponding to L.sub.4 and L.sub.5 are .theta..sub.4
.theta..sub.5 respectively is calculated by a linear interpolation
equation of .theta..sub.4 to .theta..sub.5 i.e. an equation of
.theta.=.theta..sub.4 +{(L-L.sub.4)/(L.sub.4 -L.sub.5)}.times.(.theta..sub.5
-.theta..sub.4).
Then, a method for sensing an outlet clearance of the second preferred
embodiment of the present invention will be described in reference
to FIG. 2 for showing a relation of an angle .theta. corresponding
to the distance L between the reference position S and the contact
point Pa of the mantle varying in response to abrasion. In this
preferred embodiment, a functional equation of .theta.=F(L) between
the vertical distance L ranging from the reference position S to
the contact point P of the mantle varying by wear and an angle .theta.
based on an empirical rule corresponding to the vertical distance
L is calculated and the functional equation of .theta.=F(L) is inputted
in advance into an angle inputting and outputting device.
Of course, it is apparent that the distance L and a distance between
the reference position and the contact point of the concave are
detected by the distance sensing device in the same manner as that
of the aforesaid preferred embodiment, each of the distances detected
by the distance sensing device is inputted into the distance sensing
device, the difference .DELTA.L is calculated by the clearance calculating
device, wherein the angle .theta. corresponding to the vertical
distance L ranging from the reference position detected by the distance
sensing device to a contact point of the mantle varying due to its
abrasion is calculated by the functional equation of .theta.=F(L)
by an angle inputting and outputting device, the angle .theta. calculated
by the functional equation of .theta.=F(L) is inputted into the
clearance calculating device and concurrently the outlet clearance
G is calculated in reference to a product of the aforesaid difference
.DELTA.L and the selected angle .theta., so that this preferred
embodiment has the substantially same effect as that of the aforesaid
preferred embodiment.
The method for sensing the outlet clearance in accordance with
the third preferred embodiment of the present invention will be
described in reference to FIG. 3 and FIG. 1C, wherein this cone
crusher 1 is constructed such that the concave 2 is fixed and the
mantle 3 can be moved up and down by a hydraulic cylinder (not shown).
Accordingly, in the case of this preferred embodiment, the angles
.theta..sub.0 .theta..sub.1 .theta..sub.2 .theta..sub.3 . . .
, .theta..sub.max based on empirical rule corresponding to the vertical
distances L.sub.0 L.sub.1 L.sub.2 L.sub.3 . . . , L.sub.max ranging
from the reference position S to the contact point Pa of the concave
2 which varies as shown in FIG. 1C are inputted in advance into
the angle inputting and outputting device. In addition, the vertical
distances L.sub.0 L.sub.1 L.sub.2 L.sub.3 . . . , L.sub.max and
the distance Lb ranging from the reference position S to the contact
point P of the mantle 3 are detected together by the distance sensing
device and at the same time each of the distances detected by the
distance sensing device is inputted into the clearance calculating
device and the difference .DELTA.L is calculated by the clearance
calculating device.
In concurrent with this operation, the angle .theta. corresponding
to the vertical distance L ranging from the reference position S
detected by the distance sensing device to the contact point P of
the concave 2 varying due to wear is selected from the angles .theta..sub.0
.theta..sub.1 .theta..sub.2 .theta..sub.3 . . . , .theta..sub.max
by the angle inputting device, the selected angle .theta. is inputted
into the clearance calculating device and at the same time the outlet
clearance G is calculated in reference to a product of the aforesaid
difference .DELTA.L and a cosine of the selected angle .theta.,
i.e. a product of .DELTA.L.times.cos.theta..
As being apparently understood from the foregoing description,
the matter of the present preferred embodiment differing from that
of the first preferred embodiment consists in the fact that the
mantle 3 is merely moved up and down and the outlet clearance G
is calculated in reference to the angles .theta..sub.0 .theta..sub.1
.theta..sub.2 .theta..sub.3 . . . , .theta..sub.max based on an
empirical rule in the same manner as that of the first preferred
embodiment, so that the third preferred embodiment can provide the
substantially same effect as that found in the aforesaid preferred
embodiments.
In the third preferred embodiment, there has been described the
case in which the angle .theta. corresponding to the vertical distance
L ranging from the reference position S to the contact point Pb
of the concave 2 varying due to abrasion is inputted in advance
into the angle inputting and outputting device. However, it may
also be applicable to the third preferred embodiment that the functional
equation of .theta.=F(L) is inputted in advance into the angle inputting
and outputting device as disclosed in the second preferred embodiment,
for example.
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