Field of Invention
[0001] This invention relates to a horizontal shaft impact crusher having a curtain, mounted
on a pivot shaft, against which material accelerated by an impeller can be crushed
in which the curtain can be adjusted by an adjustment system between primary and secondary
crushing settings.
Background of the Invention
[0002] Horizontal shaft impact crushers are utilized in many applications for crushing hard
material such as pieces of rock, ore etc. A horizontal shaft impact crusher is generally
made up of a housing having an inlet for material to be crushed, an outlet for material
that has been crushed, an impeller, mounted on a horizontal shaft in the crusher housing,
operative for rotating around a horizontal axis, a curtain mounted between pivot points
against which material accelerated by the impeller may be crushed, and an adjustment
bar for adjusting the position of said curtain relative to the impeller. Pieces of
rock are fed towards the impeller and are struck by beater elements mounted on the
impeller. The pieces of rock are disintegrated by being struck by the beater elements
and are accelerated and thrown against the curtains where further disintegration occurs.
[0003] The action of the impeller thus causes the material fed to the horizontal shaft impact
crusher to move freely in a crushing chamber and to be crushed upon impact against
the beater elements, against the curtains, and against other pieces of material moving
around at high speed in the crushing chamber.
[0004] In some crushers, the position of the curtain can be adjusted between first and second
crushing settings e.g. between primary and secondary or between secondary and tertiary
etc. crushing settings. The adjustment is typically made by altering the position
of the pivot points to vary the distance between the curtain and the impeller. However,
movement of the pivot points generally requires manual handling and the use of lifting
equipment which can expose operatives to safety hazards. In addition, with mobile
crushers, suitable lifting equipment may not always be available on site. Adjustment
of the position of the curtain may also be required to compensate for both curtain
wear and beater element wear.
[0005] An object of the invention is to overcome at least some of the problems of the prior
art.
Summary of the Invention
[0006] According to the invention there is provided a horizontal shaft impact crusher comprising:
a crusher housing having an inlet for material to be crushed;
an outlet for material that has been crushed;
an impeller mounted on a horizontal shaft (60) in the crusher housing and being operative
for rotating around a horizontal axis;
a curtain having an upper end and a toe end, against which material accelerated by
the impeller may be crushed, pivotably mounted at the upper end (on a pivot shaft
between first and second pivot points defining the position of the curtain relative
to the impeller, and
an adjustment system for adjusting the position of the pivot points between a first
crushing setting in which the curtain is positioned a first distance from the impeller
and a second crushing setting in which the curtain is positioned a second distance
from the impeller
wherein the adjustment system comprises
a rotatable pivot shaft support plate on the pivot shaft for supporting the pivot
shaft and defining the first pivot point and
a drive for effecting rotation of the pivot shaft support plate to adjust the position
of the first pivot point between the first and second crushing settings. The adjustment
system allows the pivot points to be repositioned without any manual intervention
or the need for lifting equipment.
[0007] In one embodiment, the adjustment system further comprises a second rotatable pivot
shaft support plate defining the second pivot point and a connector extending between
the first pivot shaft support plate and the second pivot shaft support plate to enable
synchronised positioning of the pivot points. The use of the second rotatable pivot
shaft support plate and the connector allows for the effective and simultaneous repositioning
of the pivot points.
[0008] In any embodiment, the pivot shaft support plate is attached to the pivot shaft towards
a free end of the pivot shaft. This facilitates ease of attachment of the pivot shaft
support plate to the pivot shaft.
[0009] In any embodiment, the pivot shaft support plate is an annular plate having an eccentrically
positioned pivot shaft receiving opening. By being eccentrically positioned, the pivot
shaft receiving opening is spatially moved upon rotation of the annular plate to reposition
the pivot point.
[0010] In one embodiment, the annular plate is an annular disc to allow for circumferential
contact with the drive.
[0011] In one embodiment, the annular disc is a gear and the drive comprises a complementary
drive gear engageable with the gear to effect rotation of the gear. Such a gear mechanism
ensures effective and efficient movement of the annular disc.
[0012] In one embodiment, the gear is an eccentric gear. The eccentric gear provides for
easy repositioning of the pivot points.
[0013] In any embodiment, the horizontal shaft impact crusher further comprises a motor
for powering the drive gear. The drive gear can therefore be operated independently
of the crusher motor to allow for pivot point repositioning with the crusher motor
switched off.
[0014] In one embodiment, the drive gear and the motor are mounted on the crusher housing.
The crusher housing therefore supports the drive gear and the motor.
[0015] In any embodiment of the invention, the drive comprises a linear drive engageable
with the pivot shaft support plate to effect rotation of the pivot shaft support plate.
This provides an alternative to the use of a drive gear.
[0016] In one embodiment, the linear drive comprises a hydraulic ram and cylinder. A hydraulic
ram and cylinder can be in fluid communication with the hydraulic system of the crusher.
[0017] Suitably, the linear drive further comprises a linkage between the hydraulic ram
and the pivot shaft support plate. The linkage facilitates rotation of the pivot shaft
support plate.
[0018] In another embodiment, the linear drive comprises a pneumatic linear drive. A pneumatic
linear drive can be operated independently of the crusher hydraulic system.
[0019] In another embodiment, the linear drive comprises a mechanical linear drive. A mechanical
linear drive can be operated independently of the crusher hydraulic system and can
be operated manually if required.
[0020] In any embodiment, the first crushing setting is a primary crushing setting and the
second crushing setting is a secondary crushing setting. Accordingly, the curtains
can be positioned as required in accordance with the crushing action required.
Brief Description of the Drawings
[0021] The invention will now be described, by way of example only, with reference to the
accompanying drawings in which:
Figure 1 is a partially cut away side view through a horizontal shaft impact crusher
of the invention with a first upper curtain adjustment system mounted at the free
ends of the pivot shaft of a first upper curtain of the crusher and a second lower
curtain adjustment system mounted at the free ends of the pivot shaft of a second
lower curtain of the crusher with the adjustment systems in a first crushing setting
(e.g. primary crushing setting) position;
Figure 2 is a rear perspective view of the crusher of Figure 1;
Figure 3 is an enlarged perspective view from the rear and one side of a first upper
curtain adjustment system of Figure 2;
Figure 4 is an enlarged side elevation of the adjustment system of Figure 3, and
Figure 5 is an enlarged side elevation of the adjustment system of Figure 3 in a second
crushing setting (e.g. secondary crushing setting) position.
Detailed Description of the Invention
[0022] Figures 1 and 2 show a horizontal shaft impact crusher 10 of the invention provided
with curtain adjustment systems 20.
[0023] As shown in the drawings, the horizontal shaft impact crusher 10 comprises a housing
15 having an inlet 30 for receiving material to be crushed, an outlet 40 for material
that has been crushed and an impeller 50 within the housing 15. A crusher motor, not
illustrated for reasons of maintaining clarity of illustration, is operative for rotating
a horizontal shaft 60 on which the impeller 50 is mounted. As an alternative to the
impeller 50 being fixed to the shaft 60, the impeller 50 may rotate around the shaft
60. In either case, the impeller 50 is operative for rotating around a horizontal
axis, coinciding with the centre of the horizontal shaft 60.
[0024] Internally, the housing 15 is provided with a plurality of wear protection plates
16 that are operative for protecting the walls of the housing 15 from abrasion and
from impact by the material to be crushed. Furthermore, the housing 15 comprises a
bearing 17 for the horizontal shaft 60. A lower feed plate (not shown) and an upper
feed plate (not shown) are arranged at the inlet 30. The feed plates are operative
for providing the material fed to the crusher 10 in a suitable direction with respect
to the impeller 50.
[0025] As shown particularly in Figure 1, the housing 15 houses a first upper curtain 70,
and a second lower curtain 80. Each curtain 70,80 comprises at least one wear plate
73,83 against which material may be crushed.
[0026] The illustrated impeller 50 has four beater elements 51 with each beater element
51 having a bent shape, as shown particularly in Figure 1. The area formed between
the impeller 50 and the first and second curtains 70,80 can be called a crushing chamber
11 of the crusher 10.
[0027] An upper end 71 of the first curtain 70 is mounted on a horizontal first pivot shaft
90 and an upper end 81 of the second curtain 80 is mounted on a horizontal second
pivot shaft 100 so that the pivot shafts 90,100 are suspended in the housing 15.
[0028] Material to be crushed first reaches the first curtain 70, being located upstream
of the second curtain 80 as seen with respect to the direction of travel of the material.
By means of the feed plates the material is directed towards the impeller 50 rotating
at, typically, 400-850 rpm. When the material is hit by the beater elements 51 it
is crushed and accelerated against the wear plates 73 of the first curtain 70 where
further crushing occurs. The material bounces back from the first curtain 70 and is
crushed further against material travelling in the opposite direction and, again,
against the beater elements 51. When the material has been crushed to a sufficiently
small size it moves further down the crusher chamber 11 and is accelerated, by means
of the beater elements 51, towards the wear plates 83 of the second curtain 80, being
located downstream of the first curtain 70. Hence, the material moves freely around
in the crushing chamber 11 and is crushed against the beater elements 51, against
the wear plates 73,83 respectively of the curtains 70,80 and against other pieces
of material circling around, at a high velocity, in the crusher 10.
[0029] As shall be explained more fully below, in the present embodiment, a curtain adjustment
system 20 is provided on each pivot shaft 90,100 towards a free end of each pivot
shaft 90,100 and is axially rotatable to adjust the distance between the curtains
(70,80) and the impeller (50) so that the curtains (70,80) can be easily adjusted
between a first crushing setting such as a primary crushing setting shown in Figures
1 to 4 and a second crushing setting such as a secondary crushing setting shown in
Figure 5.
[0030] As shown particularly in Figure 2, in the present embodiment, the first pivot shaft
90 extends beyond pivot shaft openings (not shown) in the housing 15 to define first
and second free ends 190,200 of the first pivot shaft 90 and a curtain adjustment
system 20 is provided at both the first free end 190 and the second free end 200.
Similarly, the second pivot shaft 100 extends beyond openings (not shown) in the housing
15 to define first and second free ends 210,220 of the second pivot shaft 100 and
a curtain adjustment system 20 is provided at the first free end 210 and the second
free end 220. However, in other embodiments, a curtain adjustment system 20 can be
provided at either free end 190,200 and 210,220 of the pivot shafts 90,100 respectively.
[0031] Figures 3 and 4 show enlarged views of the upper curtain adjustment system 20 of
Figure 2 at the free end 190 of the pivot shaft 90 - the adjustment system 20 at the
opposite free end 200 of the pivot shaft 90 being identical in configuration. Similarly,
adjustment systems 20 at the free ends 210,220 of the pivot shaft 100 are identical
in construction to the adjustment system 20 of Figures 3 and 4 described in more detail
below.
[0032] As shown in the drawings, the adjustment system 20 is generally made up of an axially
rotatable pivot shaft support plate 150 for supporting the pivot shaft 90 towards
its free end 190 at a first pivot point 110 defined in the pivot shaft support plate
150. The pivot shaft support plate 150 is rotatably mounted on a mounting ring 151
secured to the housing 15 so that the adjustment system 20 is supported on the housing
15 by the mounting ring 151 at the pivot shaft opening. The pivot shaft support plate
150 is an annular plate 230 in the form of an annular disc 245 provided with an eccentrically
positioned pivot shaft receiving opening 240, which defines the first pivot point
110, towards the periphery of the disc 245. The pivot shaft support plate 150 therefore
serves to support the pivot shaft 90 at the eccentric pivot point 110 to mount the
pivot shaft 90 in the housing 15 to in turn suspend the curtain 70 in the crushing
chamber 11 (see also Figure 1). As indicated above, the pivot shaft 90 is supported
at a second pivot point 120 similarly defined in a second identical pivot shaft support
plate 170 of an adjustment device 20 at its opposite free end 200. In analogous fashion
to the pivot shaft 90 of the upper curtain 70, the pivot shaft 100 of the lower curtain
80 is supported between first and second pivot shaft support plates 155,175 identical
in configuration to the pivot shaft support plates 150,170.
[0033] The annular disc 245 is a gear 250, which in the present embodiment is an eccentric
gear 250 which can be axially rotated by a drive 160 in the form of a complementary
drive gear 260 engaged with the eccentric gear 250. The complementary drive gear 260
is rotatably mounted on the crusher housing 15 beneath the eccentric gear 250 and
is powered by a motor 270 also mounted on the housing 15 at a motor mounting bracket
280. Accordingly, axial rotation of the support plate 150, which in the present embodiment
is the eccentric gear 250, is effected by the drive gear 260 so that the position
of the of the first pivot point 110 can be adjusted between first and second crushing
settings. Similarly, axial rotation of the second support plate 170 results in the
adjustment of the position of the second pivot point 120 between first and second
crushing settings. A connector 180, which can be a bar (not shown), extends between
the first and second support plates 150,170 and enables simultaneous and synchronised
positioning of the pivot points 110,120.
[0034] In use, the motor 270 is activated to rotate the drive gear 260 to in turn effect
axial rotation of the eccentric gear 250. This action is simultaneously performed
at the pivot shaft support plate 150 and the second pivot shaft support plate 155
at the free end 190,200 of the pivot shaft 90. As a result, the positions of the first
and second pivot points 110,120 are adjusted between the first and second crushing
settings, e.g. primary and secondary cutting setting in a safe manner without requiring
manual intervention or the use of lifting equipment. The positions of the first and
second pivot points 130,140 on first and second pivot shaft support plates 155,175
of the lower curtain 80 can be adjusted in a similar manner.
[0035] In another embodiment of the invention, the drive 160 can be a linear drive such
as a hydraulic ram and cylinder, a pneumatic linear drive or a mechanical linear drive
engageable with the pivot shaft support plate 150,155,170,175 to effect rotation of
the pivot shaft support plate 150,155,170,175. The hydraulic linear drive can also
include a linkage between the hydraulic ram and the support plate 150,155,170,175.
1. A horizontal shaft impact crusher (10) comprising:
a crusher housing (15) having an inlet (30) for material to be crushed; an outlet
(40) for material that has been crushed;
an impeller (50) mounted on a horizontal shaft (60) in the crusher housing (15) and
being operative for rotating around a horizontal axis;
a curtain (70,80) having an upper end (71,81) and a toe end (72,82), against which
material accelerated by the impeller (50) may be crushed, pivotably mounted at the
upper end (71,81) on a pivot shaft (90,100) between first and second pivot points
(110,130,120,140) defining the position of the curtain (70,80) relative to the impeller
(50), and
an adjustment system (20) for adjusting the position of the pivot points (110,120,130,140)
between a first crushing setting in which the curtain (70,80) is positioned a first
distance from the impeller (50) and a second crushing setting in which the curtain
(70,80) is positioned a second distance from the impeller (50) wherein the adjustment
system (20) comprises
a rotatable pivot shaft support plate (150,155) on the pivot shaft (90,100) for supporting
the pivot shaft (90,100) and defining the first pivot point (110,130) and
a drive (160) for effecting rotation of the pivot shaft support plate (150,155) to
adjust the position of the first pivot point (110,130) between the first and second
crushing settings.
2. A horizontal shaft impact crusher (10) as claimed in Claim 1 wherein the adjustment
system (20) further comprises a second rotatable pivot shaft support plate (170,175)
defining the second pivot point (120,140) and a connector (180,185) extending between
the first pivot shaft support plate (150,155) and the second pivot shaft support plate
(170,175) to enable synchronised positioning of the pivot points (110,120,130,140).
3. A horizontal shaft impact crusher (10) as claimed in Claim 1 or Claim 2 wherein the
pivot shaft support plate (150,155,170,175) is attached to the pivot shaft (90,100)
towards a free end (190,200,210,220) of the pivot shaft (90,100).
4. A horizontal shaft impact crusher (10) as claimed in any of Claims 1 to 3 wherein
the support shaft support plate (150,155,170,175) is an annular plate (230) having
an eccentrically positioned pivot shaft receiving opening (240).
5. A horizontal shaft impact crusher (10) as claimed in Claim 4 wherein the annular plate
(230) is an annular disc (245).
6. A horizontal shaft impact crusher (10) as claimed in Claim 5 wherein the annular disc
(245) is a gear (250) and the drive (160) comprises a complementary drive gear (260)
engageable with the gear (250) to effect rotation of the gear (250).
7. A horizontal impact crusher (10) as claimed in Claim 6 wherein the gear (250) is an
eccentric gear (255).
8. A horizontal shaft impact crusher (10) as claimed in any of Claims 5 to 7 further
comprising a motor (270) for powering the drive gear (260).
9. A horizontal shaft impact crusher (10) as claimed in Claim 8 wherein the drive gear
(260) and the motor (270) are mounted on the crusher housing (15).
10. A horizontal shaft impact crusher (10) as claimed in any of Claims 1 to 5 wherein
the drive (160) comprises a linear drive engageable with the pivot shaft support plate
(150,155,170,175) to effect rotation of the pivot shaft support plate (150,155,170,175).
11. A horizontal shaft impact crusher (10) as claimed in Claim 10 wherein the linear drive
comprises a hydraulic ram and cylinder.
12. A horizontal shaft impact crusher (10) as claimed in Claim 11 wherein the linear drive
further comprises a linkage between the hydraulic ram and the pivot shaft support
plate (150,155,170,175).
13. A horizontal shaft impact crusher (10) as claimed in Claim 10 wherein the linear drive
comprises a pneumatic linear drive.
14. A horizontal shaft impact crusher (10) as claimed in Claim 10 wherein the linear drive
comprises a mechanical linear drive.
15. A horizontal shaft impact crusher (10) as claimed in any of the preceding Claims wherein
the first crushing setting is a primary crushing setting and the second crushing setting
is a secondary crushing setting.