U.S. patent application number 15/481800 was filed with the patent office on 2017-10-12 for hose pump.
This patent application is currently assigned to ulrich GmbH & Co. KG. The applicant listed for this patent is ulrich GmbH & Co. KG. Invention is credited to Norbert BUCKLE.
Application Number | 20170292510 15/481800 |
Document ID | / |
Family ID | 58158902 |
Filed Date | 2017-10-12 |
United States Patent
Application |
20170292510 |
Kind Code |
A1 |
BUCKLE; Norbert |
October 12, 2017 |
HOSE PUMP
Abstract
A hose pump includes a hose bed having a counter support, a
carrier disk rotatable relative to the counter support, and a
number of pinch rollers and guide rollers arranged on the carrier
disk. A guide roller is arranged between two consecutive pinch
rollers, and the pinch rollers press a hose inserted into hose bed
against the counter support, while pinching the hose when the
carrier disk is rotating in the conveying direction to transport
the fluid in the hose. To ensure reliable threading of a hose
section of a pump hose, when the hose section is somewhat too short
and to prevent unthreading of the inserted hose section during
operation of the hose pump, the angular distance between a guide
roller and the pinch roller preceding the guide roller in the
conveying direction is greater than the angular distance between
this guide roller and the pinch roller following the guide roller
in the conveying direction.
Inventors: |
BUCKLE; Norbert; (Bernstadt,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ulrich GmbH & Co. KG |
Ulm |
|
DE |
|
|
Assignee: |
ulrich GmbH & Co. KG
Ulm
DE
|
Family ID: |
58158902 |
Appl. No.: |
15/481800 |
Filed: |
April 7, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04B 43/1253 20130101;
A61M 5/14232 20130101; F04B 43/0072 20130101; F04B 53/16 20130101;
F04B 43/1261 20130101; F04B 17/03 20130101; F04B 43/0081
20130101 |
International
Class: |
F04B 43/12 20060101
F04B043/12; F04B 53/16 20060101 F04B053/16; F04B 43/00 20060101
F04B043/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 11, 2016 |
DE |
20 2016 101 907.9 |
Claims
1. A hose pump to convey a fluid guided in a hose, the hose pump
comprising a hose bed having a counter support, a carrier disk
rotatable relative to counter support, a plurality of pinch rollers
arranged equidistant from each other in a peripheral direction on
the carrier disk and a plurality of guide rollers arranged
equidistant from each other in the peripheral direction on carrier
disk, wherein one of the plurality of guide rollers is arranged
between two consecutive pinch rollers in the peripheral direction
of the carrier disk and the pinch rollers press a hose inserted
into the hose bed against the counter support, when the carrier
disk is rotating in a conveying direction, while pinching the hose
against the counter support to transport the fluid in the hose in
the conveying direction, wherein an angular distance between a
guide roller and a pinch roller preceding said guide roller in the
conveying direction is greater than an angular distance between
said guide roller and a pinch roller following said guide roller in
the conveying direction.
2. The hose pump according to claim 1, wherein the angular distance
between a guide roller and a pinch roller following said guide
roller in the conveying direction is less than 60.degree. and
especially no more than 45.degree..
3. The hose pump according to claim 1, wherein the angular distance
between the guide roller and the pinch roller preceding said guide
roller in the conveying direction is greater than 60.degree. and
especially at least 75.degree..
4. The hose pump according to claim 1, wherein at least three pinch
rollers and at least three guide rollers are arranged on carrier
disk.
5. The hose pump according to claim 1, wherein a cylinder
protruding above the surface of the carrier disk is arranged in the
center of the carrier disk coaxial to the axis of rotation, the
outside diameter of the cylinder reaching roughly the outer
periphery of the pinch rollers and the guide rollers lying radially
farther outward.
6. The hose pump according to claim 5, wherein the radial distance
between the outer surface of cylinder and the outer periphery of
the pinch rollers and the guide rollers is smaller than the
diameter of the hose inserted into the hose bed.
7. The hose pump according to claim 1, wherein the pinch rollers
are designed to be essentially cylindrical and to have a smooth
outer surface, the outer periphery of the pinch rollers being
formed by the smooth outer surface.
8. The hose pump according to claim 1, wherein the guide rollers
are essentially cylindrical and have a guide groove running in the
peripheral direction on the outer periphery.
9. The hose pump according to claim 8, wherein the guide groove of
each guide roller has a semicircular cross section.
10. The hose pump according to claim 1, wherein the pinch rollers
and/or the guide rollers are mounted to rotate on the carrier
disk.
11. The hose pump according to claim 1, wherein a hose inserted
into the hose bed lies on a guide surface formed by the surface of
the carrier disk.
12. The hose pump according to claim 1, wherein the axis of
rotation of the carrier disk and the axes of the pinch rollers and
the guide rollers are parallel to each other.
13. The hose pump according to claim 1, wherein the carrier disk
and/or the pinch rollers mounted to rotate on the carrier disk
and/or the guide rollers mounted to rotate on the carrier disk are
placed in rotation by a drive, when the hose pump is running.
14. The hose pump according to claim 1, in which the magnitude of
the relative angular difference between the angular distance
between a guide roller and the pinch roller preceding said guide
roller in the conveying direction and the angular distance between
said guide roller and the pinch roller following said guide roller
in the conveying direction lies in the range from 0.2 to 0.5.
15. The hose pump according to claim 1, in which the magnitude of
the relative angular difference between the angular distance
between a guide roller and a pinch roller preceding said guide
roller in the conveying direction and the angular distance between
said guide roller and the pinch roller following said guide roller
in the conveying direction lies at 0.25.
16. The hose pump according to claim 1, in which the magnitude of
the relative angular difference between the angular distance
between the guide roller and the pinch roller preceding said guide
roller in the conveying direction and the angular distance between
said guide roller and the pinch roller following said guide roller
in the conveying direction lies at 0.33.
17. The hose pump according to claim 1, wherein the counter support
with an essentially circular segment shape emerges tangentially
outwards in the area of the hose output of hose bed.
18. A hose pump to convey a fluid guided in a hose, the hose pump
comprising a hose bed having a counter support, a carrier disk
rotatable relative to counter support, a plurality of pinch rollers
arranged equidistant from each other in a peripheral direction on
the carrier disk and a plurality of guide rollers arranged
equidistant from each other in the peripheral direction on carrier
disk, wherein one of the plurality of guide rollers is arranged
between two consecutive pinch rollers in the peripheral direction
of the carrier disk and the pinch rollers press a hose inserted
into the hose bed against the counter support, when the carrier
disk is rotating in a conveying direction, while pinching the hose
against the counter support to transport the fluid in the hose in
the conveying direction, wherein a cylinder protruding above the
surface of the carrier disk is arranged in the center of the
carrier disk coaxial to the axis of rotation, the outside diameter
of the cylinder reaching roughly the outer periphery of the pinch
rollers and the guide rollers lying radially farther outward.
19. The hose pump according to claim 18, wherein the radial
distance between the outer surface of the cylinder and the outer
periphery of the pinch rollers and the guide rollers is smaller
than the diameter of the hose inserted into hose bed.
Description
FIELD OF THE DISCLOSURE
[0001] The disclosure relates to a hose pump.
BACKGROUND
[0002] Such hose pumps are known, for example, from DE 10 2014 104
320 B1 and DE 102010 000 594 A1. These known hose pumps have a hose
bed into which a hose section of a hose bent into a loop can be
inserted. The known hose pumps also include a counter support and a
carrier disk rotatable relative to the counter support, on whose
top a number of pinch rollers and a number of guide rollers are
arranged. Both the pinch rollers and the guide rollers are arranged
equidistant from each other in the radially outer area of the
carrier disk and in the peripheral direction of the carrier disk,
one guide roller each being arranged between two consecutive pinch
rollers in the peripheral direction of the carrier disk. For
example, three pinch rollers and three guide rollers are provided
in an embodiment example of the known hose pumps, which have an
angular distance of 60.degree. relative to the adjacent pinch
roller or guide roller in the peripheral direction of the carrier
disk. The pinch rollers have a smooth outer periphery and press a
hose inserted into the hose bed against the counter support, while
squeezing the hose, when the carrier disk is rotating in a
conveying direction, in order to transport fluid situated in the
hose in the conveying direction. The cylindrical guide rollers have
a guide groove running in the peripheral direction on their outer
periphery to accommodate the radially inner hose half of the hose
section and ensure exact positioning and guidance of the hose in
the hose bed both during threading of the hose section into the
hose bed and during pump operation.
[0003] A motor-driven threading device, as described, for example,
in EP 2542781, can be used for automated threading of the hose
section into the hose bed. As an alternative, the hose section can
also be pressed with a hold-down device against a support surface
at the entry to the hose bed during threading into the hose bed and
can be grasped by one of the guide rollers, while the carrier disk
is being rotated, and then pulled into the hose bed, in which case
the radially inner area of the hose section is taken up in the
guide groove of the guide roller and press downward in the axial
direction onto a support surface in the hose bed. Problems can
occur in this case when the hose section is too short. There is
then the risk that the unduly short hose section will be stretched
while being threaded and placed under tensile stress, and thereby
slip out of the guide groove of the guide roller.
[0004] When the hose section inserted into the hose bed is too
long, problems can occur during operation of the known hose pumps
because the hose section at the output of the hose bed forms a loop
protruding above the support surface of the hose bed and is
therefore not cleanly guided in the hose bed. In particular, at
very high pump pressures, which can reach up to 20 bar during the
intended operation of the hose pump, there is the risk that the
downstream end of the hose section inserted into the hose bed will
slip out of the guide groove of the guide rollers and thereby be
raised from the support surface of the hose bed. This can mean that
the hose section automatically and undesirably unthreads during
operation of the hose pump.
SUMMARY OF THE DISCLOSURE
[0005] Starting from the foregoing, one embodiment of the
disclosure modifies a generic hose pump so that reliable threading
of the hose section of a pump hose can also be ensured when the
hose section is somewhat too short in comparison with the inner
periphery of the counter support. Automatic unthreading of the
inserted hose section is also to be prevented during operation of
the hose pump, especially under high pump pressures, and the
service life of the pump hose can be lengthened.
[0006] Other preferred embodiments of the hose pump are also
disclosed.
[0007] In an embodiment, the hose pump according to the disclosure
has a hose bed for insertion of a hose section of a pump hose, a
counter support, a carrier disk rotatable relative to the counter
support, a number of pinch rollers arranged on the carrier disk
equidistant from each other in the peripheral direction and a
number of guide rollers arranged on the carrier disk equidistant
from each other in the peripheral direction, one guide roller being
arranged between two consecutive pinch rollers in the peripheral
direction of the guide disk, and the pinch rollers press a hose
(hose section) inserted into the hose bed against the counter
support, while squeezing the hose as the carrier disk is rotating
in the conveying direction, in order to transport a fluid situated
in the hose in the conveying direction.
[0008] Unlike the known hose pumps cited above, the pinch rollers
and guide rollers in the hose pump according to the disclosure are
not all arranged symmetrically over the periphery of the carrier
disk equidistant from each other. The guide rollers in the hose
pump according to the disclosure are set back with reference to the
pinch rollers following them in the conveying direction (direction
of rotation of the carrier disk during pump operation of the hose
pump), i.e., the angular distance (.delta.) between a guide roller
and the pinch roller following this guide roller in the conveying
direction is smaller than the angular distance (.DELTA.) between
this guide roller and the pinch roller preceding this guide roller
in the conveying direction.
[0009] This arrangement of the pinch rollers and the guide rollers
on the carrier disk prevents the upstream section of the hose from
slipping out of the guide groove of the guide roller during
threading of the hose into the hose bed, because, during rotation
of the carrier disk, the guide roller directly (i.e., with only a
small angular distance .delta.) follows a pinch roller, which
presses the upstream section of the hose against the counter
support and thereby fixes the position in the hose bed of the
section of the hose already introduced to the hose bed.
[0010] Due to of the arrangement of the pinch rollers and the guide
rollers on the carrier disk according to the disclosure, during
pump operation of the hose pump, undesired unthreading of the hose
is prevented, because each pinch roller during rotation of the
carrier disk directly, i.e., at only a small angular distance
.delta., leads a guide roller, which reliably secures the
downstream section of the hose even at high pump pressures in the
hose bed and prevents the downstream end of the hose at the output
of the hose bed from bulging into a loop while the section of the
hose lying somewhat farther back in the conveying direction is
pressed against the counter support by the pinch roller.
[0011] The magnitude of the relative angular difference
(.DELTA.-.delta./.DELTA.+.delta.) between the angular distance
.DELTA. between the guide roller and the pinch roller preceding
this guide roller in the conveying direction and the angular
distance .delta. between this guide roller and the pinch roller
following this guide roller in the conveying direction is
preferably in the range from 0.2 to 0.5.
[0012] The guide rollers and the pinch rollers are expediently
arranged rotationally symmetrically on the carrier disk (with
reference to the axis of rotation of the carrier disk as center of
symmetry), the angle of symmetry being 360.degree./n, where n is
the number of guide rollers and pinch rollers.
[0013] In a preferred embodiment, the hose pump according to the
disclosure has three or more pinch rollers and an equal number of
guide rollers, which are arranged on the radial outer edge of the
carrier disk, so that the angular distance (.delta.) between each
guide roller and the pinch roller following the guide roller in the
conveying direction is less than 60.degree., and, in the case of
three guide rollers and three pinch rollers, preferably 45.degree..
Correspondingly, the angular distance (.DELTA.) between a guide
roller and the pinch roller preceding this guide roller in the
conveying direction is greater than 60.degree. and particularly at
least 75.degree.. In this arrangement with three pinch rollers and
three guide rollers the magnitude of the relative angular distance
preferably lies at .DELTA.-.delta./.DELTA.+.delta.=0.25. In an
alternative arrangement with four pinch rollers and four guide
rollers, the magnitude of the relative angular distance preferably
lies at .DELTA.-.delta./.DELTA.+.delta.=0.33.
[0014] According to an aspect of the disclosure independent of the
arrangement of pinch rollers and guide rollers on the carrier disk
or combinable with it, a cylinder protruding above the surface of
the carrier disk is arranged in the center of the carrier disk
coaxial to its axis of rotation, the outside diameter of which at
least roughly reaches the outer periphery of the pinch rollers and
guide rollers lying radially farther outward. The cylinder, located
radially inward relative to the guide rollers and the pinch rollers
on the carrier disk, prevents a section of the hose from lying on a
radially inner (relative to the carrier disk) portion of the outer
periphery of the guide rollers during threading of the hose and
therefore from not being correctly grasped by this guide roller,
and it can be introduced into the hose bed between the outer
periphery of the guide roller and the counter support. It is
expedient for this purpose if the radial distance between the outer
surface of the cylinder and the outer periphery of the guide
rollers is smaller than the diameter of the hose being introduced
to the hose bed.
[0015] In order to rotate the carrier disk during operation of the
pump, the carrier disk is connected to a shaft which is coupled to
a drive and can be placed in rotation by it. The guide rollers and
the pinch rollers are preferably mounted to rotate on the carrier
disk in order to permit frictionless rolling on the surface of the
hose. However, they can also be non-rotatably connected to the
carrier disk. The axis of rotation of the carrier disk (axis of the
shaft) and the axes of the pinch rollers and guide rollers then run
parallel to each other. If the guide rollers and the pinch rollers
are mounted to rotate on the carrier disk, they can be placed in
rotation by a drive (optionally via a gear mechanism), in which the
drive is preferably a drive that also rotates the carrier disk. The
guide rollers and the pinch rollers, however, can also be mounted
to rotate on the carrier disk without coupling to a drive.
[0016] The pinch rollers are expediently made at least essentially
cylindrical and with a smooth outer surface, the outer periphery of
the pinch rollers that presses the hose against the counter support
being formed by the smooth outer surface. The guide rollers
expediently have on their outer periphery a continuous guide
groove, which is adapted to the shape of the hose and is designed
with a semicircular cross section, for example, for a hose with a
circular cross section. Owing to shaping of the guide groove on the
outer periphery of the guide rollers, these guide rollers are
nestled on the surface of the hose without squeezing it, when the
hose pump is running. Reliable and uniform guidance of the hose in
the hose bed is thus ensured when the hose pump is running.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] These and additional advantages and features of the hose
pump according to the disclosure are apparent from the embodiment
example described below with reference to the accompanying
drawings. The drawings show:
[0018] FIG. 1: Perspective view of a hose pump according to the
disclosure with hose inserted therein;
[0019] FIG. 2: Cross section of the hose pump of FIG. 1 (without
hose).
DETAILED DESCRIPTION
[0020] An embodiment example of a hose pump according to the
disclosure is shown in FIG. 1 and FIG. 2 in a perspective view
(with inserted hose 16) and a sectional view (without hose). The
hose pump serves to convey a fluid guided in a hose 16 or an
injection fluid for a medical, especially intravenous, injection.
The hose pump is arranged in a pump housing 14, on which a
pivotable housing cover is connected by means of a fastening device
18, not shown here for reasons of improved clarity.
[0021] The hose pump comprises a carrier disk 1, which is coupled
via a drive shaft 10 arranged centrally in the carrier disk 1 to a
drive 7. The drive 7 is an electric motor, for example. When drive
7 is running, the carrier disk 1 is placed in rotation about an
axis of rotation A in conveying direction F, via the drive shaft
10, which is non-rotatably connected to carrier disk 1. The
conveying direction F in the depicted embodiment example (direction
of rotation of the carrier disk during pump operation) is
clockwise.
[0022] The hose pump also comprises a hose bed 2 with a hose input
2a and a hose output 2b, as well as a counter support 4. The
counter support 4 is formed by the inner periphery of a circular
segment, which is open in the area of the hose input 2a and the
hose output 2b of hose bed 2 to introduce a hose 16. The hose bed 2
serves to accommodate a hose section of a pump hose (the hose
section is hereinafter referred to as a hose), in which a fluid
(for example, an injection fluid for intravenous injection into the
bloodstream of a patient) is guided. A hose inserted into hose bed
2 then lies on a guide surface 2c formed by the surface of carrier
disk 1. The counter support 4 runs tangentially outwards in the
area of hose output 2b of hose bed 2, as is apparent from the
figures.
[0023] Several pinch rollers 3 are arranged on the surface of the
carrier disk 1 in the radially outer section (near its outer
periphery). The axes 3' of the pinch rollers then lie on a circular
path concentric to the axis of rotation (A) of carrier disk 1
(dashed line in FIG. 2). In the embodiment example of the hose pump
according to the disclosure illustrated here, three such pinch
rollers 3a, 3b, 3c are provided and are distributed uniformly over
the periphery of carrier disk 1. If reference is subsequently made
to identically designed pinch rollers 3a, 3b, 3c, reference numeral
3 is used. The pinch rollers 3 are at least essentially cylindrical
with a smooth outer surface.
[0024] A guide roller 5 is arranged on carrier disk 1 between
adjacent pinch rollers 3. The axes 5' of the guide rollers 5 then
also lie on the circular path (dashed line in FIG. 2) running
concentric to axis or rotation (A) of carrier disk 1. In the
embodiment example of the hose pump according to the disclosure
illustrated here, three such guide rollers 5a, 5b, 5c are provided
and are arranged uniformly distributed over the periphery of
carrier disk 1 (and on the dashed circular path). If reference is
subsequently made to identically formed guide rollers 5a, 5b, 5c,
reference numeral 5 is used.
[0025] The guide rollers 5 have a cylindrical basic shape and a
continuous guide groove 11 in the peripheral direction on their
outer periphery (on the cylinder surface). Both the pinch rollers 3
and the guide rollers 5 are expediently mounted to rotate on
carrier disk 1, the axes of rotation 3' of the pinch rollers 3 and
the axes of rotation 5' of the guide rollers 5 each running
parallel to drive shaft 10. The pinch rollers 3 and the guide
rollers 5 can then be mounted either to rotate freely on carrier
disk 1 or also coupled to drive 7 via a clutch. If the pinch
rollers 3 and/or the guide rollers 5 are coupled via a clutch to
drive 7, they are placed in rotation in the same direction as
carrier disk 1 (clockwise) when drive 7 is running.
[0026] The three pinch rollers 3a, 3b, 3c and the three guide
rollers 5a, 5b, 5c are arranged on the radial outer edge of carrier
disk 1 so that the angular distance .delta. between each guide
roller and the pinch roller following a guide roller in the
conveying direction is less than 60.degree. and, as in the depicted
embodiment example of FIGS. 1 and 2, especially 45.degree. .
Correspondingly, the angular distance .DELTA. between a guide
roller and the pinch roller preceding this guide roller in the
conveying direction is greater than 60.degree. and amounts to
75.degree. in the depicted embodiment example. In the embodiment
example depicted in FIGS. 1 and 2, the angular distance .delta.
between the guide roller 5a and the pinch roller 3a following this
guide roller 5a in conveying direction F, .delta.=45.degree..
Correspondingly, the angular distance A between the guide roller 5a
and the pinch roller 3b preceding this guide roller 5a in the
conveying direction lies at .DELTA.=75.degree..
[0027] A hose inserted into hose bed 2 is guided by the guide
rollers 5 by engaging the hose in the peripheral guide grooves 11
of the guide rollers. The hose is thus held on the guide surface 2c
formed by the surface of carrier disk 1 and the slipping out of the
hose from the hose bed 2 is prevented when the pump is running.
[0028] In the center of carrier disk 1, a cylinder 6 protruding
above the surface of carrier disk 1 coaxial to its axial of
rotation A is arranged, which encloses drive shaft 10 and whose
(outside) diameter D at least roughly reaches the outer periphery
of the pinch rollers and guide rollers lying radially farther
outward, i.e., a small (as possible) distance exists between the
outer periphery of cylinder 6 and the outer periphery of the pinch
rollers and guide rollers (FIG. 1). The cylinder 6, as is apparent
from FIG. 2, can be designed as a hollow cylinder or also as a
solid cylinder. The cylinder 6 is expediently non-rotatably
connected to carrier disk 1. During threading of the hose, the
cylinder 6 prevents the hose from lying on the radially inwardly
pointing side of the guide rollers 5 and therefore from not being
properly threaded into the hose bed 2 between the outer periphery
of the pinch rollers 3 and the counter support 4. For this purpose,
the radial distance between the outer surface of the cylinder and
the outer periphery of the guide rollers should be less than the
diameter of the hose being introduced into the hose bed. The height
of the cylinder 6 (in the axial direction) is then expediently
adjusted to the height of the pinch rollers and the guide rollers
and has at least the same height as the pinch rollers and the guide
rollers. The cylinder 6 expediently protrudes somewhat beyond the
pinch rollers and the guide rollers in the axial direction in order
to permit unhindered sliding of the hose into guide bed 2.
[0029] The housing 14 of the pump contains a cassette receptacle 13
designed as a recess in the housing (FIG. 2) for insertion of a
replaceable cassette 15 (FIG. 1). A guide channel 15b and a pump
hose 16 connected to it, in which the fluid being conveyed is
guided, are integrated in the cassette 15 depicted in FIG. 1. A
loop- or arc-shaped section of the pump hose then protrudes from
housing 15a of the cassette. Several connection tubes 17a, 17b, 17c
are arranged on the top of the cassette 15, which can be connected
to supply bottles for fluids being injected (for example, contrast
agent). The connection tubes 17a, 17b, 17c are connected to the
pump hose 16 via the guide channel 15b. A connector 16a is arranged
laterally on cassette 15, to which a patient tube can be connected
in order to connect it to pump hose 16.
[0030] An unthreading device with a protrusion 8 protruding above
the surface of carrier disk 1 is arranged on hose output 2b, as is
known from DE 10 2014 104 320 B3, to which reference is made
here.
[0031] For operation of the hose pump, the section of the pump hose
protruding from the cassette is introduced to the hose bed 2, the
hose being guided by the guide rollers 5 and then running at
limited distance and essentially parallel to the surface of the
support disk 1 between the outer periphery of pinch rollers 3 and
the counter bearing 4 as well as between the guide groove 11 of
guide rollers 5 and counter bearing 4. The (radial) distance
between the outer periphery of pinch rollers 3 is then chosen
smaller than the diameter of the hose so that the hose is clamped
between the outer periphery of pinch rollers 3 and counter bearing
4 with squeezing of the flexible hose.
[0032] During pump operation of the hose pump, the carrier disk 1
(and optionally the pinch rollers 3 and the guide rollers 5
arranged on it via a gear mechanism) is placed in rotation in
conveying direction F by drive 7. In the embodiment example
depicted in the figures, the carrier disk 1 is rotated clockwise
during pump operation. The section of the hose lying in hose bed 2
is then pressed by the pinch rollers 3 against counter support 4 so
that the hose is intermittently pinched and the fluid situated in
the hose conveyed in the direction from hose input 2a to hose
output 2b. The guide rollers 5 then ensure reliable and uniform
positioning of a section of the hose in hose bed 2 by engaging the
hose in guide groove 11 of guide rollers 5 and guiding it in so
doing.
[0033] A threading device is expediently provided in the area of
the hose input 2a for threading of the section of the hose
protruding from the cassette. This threading device can be formed
by a motor-driven screw spindle, as is known from DE 10 2010 000
594 B4, to which reference is made here. A more cost-effective
threading device that dispenses with the use of a motor-driven
screw spindle is described in DE 10 2014 104320 A1, to which
reference is made here.
[0034] During threading of the hose into the hose bed, the
arrangement of pinch rollers 3 and guide rollers 5 on carrier disk
1 prevents the upstream section of the hose from slipping out of
the guide groove 11 of the guide roller lying in the area of hose
input 2a during threading (this is guide roller 5a in FIGS. 1 and
2). When the carrier disk is rotated, the pinch roller 3a directly
following this guide roller 5a at the small angular distance 6,
then presses the upstream section of the hose that has already been
threaded by the leading guide roller 5a against the counter support
4 and thereby fixes in hose bed 2 the position of the section of
the hose already introduced into the hose bed. This prevents a
somewhat too short hose from being strongly stretched during
threading and from slipping out of the guide groove 11 of guide
roller 5a.
[0035] After threading of the section of the hose protruding from
the cassette into the hose bed 2 in the manner described in DE 10
2014 104320 A1 (to which reference is made here), the pump can be
operated to convey the fluid situated in the hose in its conveying
direction F. For this purpose, the carrier disk 1 in the embodiment
example illustrated here is rotated by drive 7 clockwise so that
the pinch rollers 3 press the hose against the counter support 4 by
pinching it and thereby transport the fluid situated in the hose in
the conveying direction.
[0036] By guiding the hose in the hose pump according to the
disclosure in the region of the hose output 2b of the hose bed 2,
it is ensured that the pinch roller passing by during pump
operation (this is pinch roller 3c in the drawings) only passes
over the hose section inserted there when it is already completely
unloaded because of the counter support 4 emerging there
tangentially outward. The service life of the hose is thereby
extended. In known hose pumps, there is the risk that a pinch
roller will travel over the hose in the area of the hose output of
the hose bed across the conveying direction F and still press it
against counter support 4 so that increased flexing occurs and
therefore increased mechanical loading of the hose material.
Because of the higher mechanical loading, the hose more quickly
loses its rigidity and must be replaced sooner since it can no
longer withstand the pressure load.
[0037] The disclosure is not limited to the embodiment depicted in
the drawing. For example, the number of pinch rollers 3 and guide
rollers 5 can be chosen differently. However, it is expedient to
provide equally many guide rollers and pinch rollers, for example,
four pinch rollers 3 and four guide rollers 5, which are arranged
in alternating sequence on the carrier disk 1 so that their axes
lie on a circular path running concentrically around the axis of
rotation A of carrier disk 1. The angular distances between the
pinch rollers and between the guide rollers are then equidistant
from each other. With four guide and pinch rollers, this angular
distance between the guide and pinch rollers is 90.degree..
* * * * *