[0001] The present invention relates to a method and an apparatus for washing parts.
[0002] At present, parts for industrial and any other use are washed in apparatus where
the part to be washed is moved relative to the washing liquid spraying nozzles or
in apparatus where the nozzles are moved relative to the part to be washed. In both
cases, the part that moves relative to the other, whether nozzle or part to be washed,
moves at a substantially constant speed and the jets of washing liquid strike the
different points on the part in totally random fashion and only for the instant in
which they are in the path of the corresponding nozzle.
[0003] This conventional method is not entirely effective in removing dirt from the part,
especially from cavities or holes which the jets of washing liquid cannot easily reach.
[0004] At present, a hole, especially a deep blind hole, can only be satisfactorily cleaned
by hand, using a suitable spray gun to direct a jet of washing liquid into it.
[0005] Another disadvantage of conventional machines is that, because the washing liquid
is recirculated by a pump from a tank where the washing liquid collects to all the
spraying nozzles, the pressure of the washing liquid flow is considerably divided
and the strength of the washing jet consequently reduced.
[0006] The present invention provides a method for washing a part, especially a part with
cavities extending inwards from its surfaces, by using means for spraying a washing
liquid onto a surface of the part, said method envisaging that the part and the means
for spraying the washing liquid be moved relative to each other so as to enable the
surface of the part to be thoroughly washed.
[0007] According to one advantageous aspect of the invention, the part to be washed and
the means for spraying the washing liquid are moved relative to each other in steps
of predetermined length so that the washing liquid can enter the cavities in the part.
[0008] In this way, the surface of the part, including the insides of cavities, can be thoroughly
cleaned without having to clean the part by hand.
[0009] The secondary claims refer to other advantageous aspects of the invention.
[0010] Further technical characteristics and advantages of the invention are apparent from
the detailed description which follows, made with reference to the accompanying drawings,
which illustrate a preferred embodiment of the invention and in which:
- Figure 1 is a schematic transversal view of the preferred embodiment of the part washing
machine;
- Figure 2 is a schematic longitudinal view of a detail of the preferred embodiment,
showing the area occupied by the part to be washed.
[0011] Figures 1 and 2 illustrate a preferred embodiment 10 of the present apparatus for
the washing of parts 12. The present apparatus is designed in particular to wash irregularly
shaped parts, especially parts 12 having cavities or holes 16 extending inwards from
their outer surfaces 14a, 14b, 14c, 14d, 14e, 14f to be washed, where such cavities
or holes are very different in size and shape and are randomly positioned on each
part 12. As illustrated, the present preferred embodiment of the washing apparatus
comprises a frame 18 supporting a base 20 that supports the part 12, the base consisting
of a mobile carriage 20 with wheels 22 running on rails 24 which are fixed to the
frame 18 of the washing machine 10. The base 20 is open at the bottom, since it is
made up simply of longitudinal bars and crossbars which allow the washing water to
reach the part from below, as described in more detail in another part of this description.
[0012] As shown schematically in Figure 1, the frame 18 of the washing machine also comprises
a tank 13 located under the part supporting base 20 and designed to collect the washing
liquid 15 consisting preferably of water mixed with a suitable detergent or other
cleaning agent.
[0013] The present embodiment also has means designed to spray the washing liquid at a corresponding
face of the part 12 opposite it and comprising spraying elements 26a, 26b, 26c, 26d
for cleaning the longitudinal faces 14a, 14b, 14c, 14d of the part 12, and spraying
elements 26e, 26f for cleaning the transversal faces 14e, 14f of the part 12.
[0014] As illustrated, each of the washing liquid spraying elements 26a, 26b, 26c, 26d,
26e, 26f comprises a plurality of nozzles 28, each of which sprays a jet 30 of washing
liquid.
[0015] In particular, the nozzles 28 of each of the washing liquid spraying elements are
made on one side of a corresponding tubular component 25a, 25b 25c, 25d, 25e, 25f,
in line and closely spaced in such a way that the nozzles 28 strike the part 12 to
be washed along a corresponding band of the part 12 itself.
[0016] The spacing between the nozzles 28 (as shown in Figure 1) is such that water jets
form a comb-like configuration which enables the washing liquid to make effective
contact with the surface of the part 12 in the area that is struck by the "comb" of
water jets. This comb-like configuration, which is obtained by setting the nozzles
close together, makes it possible to effectively clean every point on the surface
of the part struck by the flow of washing liquid.
[0017] To wash the corresponding face 14a, 14b, 14c, 14d, 14e, 14f of the part 12, the present
embodiment comprises means for moving the part 12 to be washed and the washing liquid
spraying means 26a, 26b, 26c, 26d, 26e, 26f relative to each other.
[0018] The means for moving the part 12 relative to the washing liquid spraying means are
designed to move the part 12 in a straight, longitudinal direction and, in the present
preferred embodiment, consist of a drive chain 32 whose active branch drives the carriage
20 in a longitudinal direction through a corresponding toothed gear 34 which is in
turn driven by a motor (not illustrated).
[0019] The effect of moving the part 12 in this way, as described in more detail below,
is to clean only the longitudinal faces 14a, 14b, 14c, 14d of the part 12.
[0020] To also clean the transversal faces at the head and tail ends 14e, 14f of the part
12, there are means (illustrated schematically by the two-way arrow MT in Figure 1)
for also moving the washing liquid spraying means 26e, 26f relative to the part 12.
[0021] In another embodiment, there may be a smaller number of washing liquid spraying elements,
even a single nozzle for spraying a single washing liquid jet or a single element
with a plurality of spraying nozzles. In this case, in order to wash the plurality
of cavities in the part, either the liquid spraying means are moved relative to the
part to be washed or the part to be washed is moved while the spraying means are kept
in a fixed position. In yet another embodiment, both the washing liquid spraying means
and the part to be washed may be moved together according to appropriately synchronized
reciprocal movements.
[0022] Suitable means are provided to control the relative movements of the part 12 and
the washing liquid spraying means 26a, 26b, 26c, 26d, 26e, 26f.
[0023] The control means should be such as to make the part 12 and the washing liquid spraying
means 26a, 26b, 26c, 26d, 26e, 26f move relative to each other in steps of predetermined
length so that the part and the washing liquid spraying means assume relative positions
such that at least one jet of washing liquid is sprayed into each of the cavities
in the corresponding faces 14a, 14b, 14c, 14d, 14e, 14f of the part 12. The hold time
in each predetermined working position during which washing liquid is sprayed may
be fixed or variable, according to the features of each single hole or cavity.
[0024] According to the present preferred embodiment, the control means comprise sensor
means 36, 38 capable of detecting the relative position of the part 12 and the washing
liquid spraying means 26a, 26b, 26c, 26d, 26e, 26f.
[0025] In this preferred embodiment, said sensors consist of an encoder 36 that detects
the angular position of the drive gear 34 and a transducer 38 that detects the position
of the corresponding means 26e, 26f for washing the transversal faces of the part
12.
[0026] The control means also comprise centralized, electronic processing means 40 (for
example, a PLC) which generate a signal in response to the signal from the sensor
means 36 in order to move the part 12 and the washing liquid spraying means 26a, 26b,
26c, 26d, 26e, 26f relative to each other in steps of predetermined length.
[0027] The electronic processing means 40 essentially comprise a central processing unit,
a memory which, amongst other things, contains a program to control the operation
of the machine, and input and output units.
[0028] The machine operator starts by scanning the part to be washed so as to enter part
shape data in the processor 40. This data is then used by the program to control the
relative movements of the part and washing liquid spraying means in such a way as
to thoroughly wash the part, including holes and irregular surfaces. The part carriage
20 is equipped with means designed to position the part itself at appropriate reference
points.
[0029] According to another advantageous aspect, means are also envisaged for selectively
feeding the liquid to the washing liquid spraying means 26a, 26b, 26c, 26d, 26e, 26f.
[0030] The means for selectively feeding the liquid to the washing liquid spraying means
26a, 26b, 26c, 26d, 26e, 26f comprise a single pump 42 for supplying and recirculating
the liquid 15 by pumping it from the tank 13 through pipes 27a, 27b, 27c 27d, 27e,
27f to the corresponding means 26a, 26b, 26c, 26d, 26e, 26f that spray the washing
liquid 15 onto the part 12.
[0031] The present apparatus is therefore capable of locating each hole in the part and
spraying a jet of washing liquid into it. Parts of any shape can be thoroughly washed.
[0032] The selective feed means comprise appropriate means 44 for distributing the flow
of washing liquid to the spraying means 26a, 26b, 26c, 26d, 26e, 26f.
[0033] The electronic processing means 40 also control the flow distributing means 44 in
such a way as to activate the nozzles 28 of only one spraying element at a time, so
that the pressure of the washing liquid jet delivered by each single nozzle is higher
and, consequently, the jet is more powerful and more effective in removing the dirt
from the surface of the part to be washed. The washing liquid may be supplied to a
predetermined number of spraying elements or groups of nozzles instead of just to
a single spraying element or a single group of nozzles, so that the corresponding
number of jets are delivered at a pressure that is in any case higher than the pressure
that would be obtained if all the spraying elements of the machine were activated
at the same time.
[0034] In a preferred washing method therefore, the part to be washed is moved longitudinally
by a series of steps, so as to wash the corresponding face of the part, and then returned
to the starting position.
[0035] The head and tail ends of the part may be washed simultaneously or in sequence after
the last longitudinal face has been washed.
[0036] According to another advantageous aspect of the present embodiment, there are means
(illustrated by the two-way arrows labelled M26a, M26b, M26c M26d, M26e, M26f) each
designed to move the corresponding washing liquid spraying element 26a, 26b, 26c,
26d, 26e, 26f in a direction parallel to each face 14a, 14b, 14c, 14d, 14e, 14f and
perpendicular to the path of the jet of washing liquid of the corresponding face 14a,
14b, 14c, 14d, 14e, 14f. In this way, it is possible to adjust the washing liquid
spraying means 26a, 26b, 26c, 26d, 26e, 26f relative to the corresponding cavities
16 to be washed so that they are in the ideal position to be effectively washed. In
the present embodiment, the adjusting movements are vertical for the spraying elements
26a, 26c, 26e, 26f and horizontal for the spraying elements 26b, 26d.
[0037] According to yet another advantageous aspect of the present embodiment, there are
also means (illustrated by the two-way arrows labelled D26a, D26b, D26c D26d, D26e,
D26f) each designed to move the corresponding washing liquid spraying element 26a,
26b, 26c, 26d, 26e, 26f in a direction perpendicular to each face 14a, 14b, 14c, 14d,
14e, 14f. This makes it possible to adjust the distance of the washing liquid spraying
means 26a, 26b, 26c, 26d, 26e, 26f from the corresponding faces 14a, 14b, 14c, 14d,
14e, 14f so as to obtain even better positioning of the nozzles relative to the holes
in the part to be washed.
[0038] The adjusting movements perpendicular to the paths of the washing jets and to the
faces of the spraying elements 26a, 26b, 26c, 26d, 26e, 26f are controlled by the
electronic processing means 40 according to the position signals generated by the
position sensors 36 and 38.
1. A method for washing a part (12), especially a part (12) having cavities (16) extending
inwards from its outer surfaces (14a, 14b, 14c, 14d, 14e, 14f) to be washed, where
washing liquid spraying means (26a, 26b, 26c, 26d, 26e, 26f) are used to wash a corresponding
surface (14a, 14b, 14c, 14d, 14e, 14f) of the part (12); and where the part (12) and
the washing liquid spraying means (26a, 26b, 26c, 26d, 26e, 26f) are moved relative
to each other in such a way as to wash the corresponding surface (14a, 14b, 14c, 14d,
14e, 14f), said method being characterized in that the part (12) and the washing liquid
spraying means (26a, 26b, 26c, 26d, 26e, 26f) are moved relative to each other in
steps of predetermined length so that the washing liquid can be sprayed into the cavities
(16) in the surfaces (14a, 14b, 14c, 14d, 14e, 14f) of the part (12).
2. The method according to claim 1, characterized in that the part (12) being washed
moves in steps.
3. The method according to either of the foregoing claims, characterized in that the
washing liquid spraying means (26e, 26f) move in steps.
4. The method according to any of the foregoing claims or according to the preamble to
claim 1, characterized in that the washing liquid spraying means comprise washing
liquid spraying elements (26a, 26b, 26c, 26d, 26e, 26f) each designed to wash a corresponding
face (14a, 14b, 14c, 14d, 14e, 14f) of the part (12); and in that the washing liquid
is selectively fed to one or to a predetermined number of said washing liquid spraying
elements (26a, 26b, 26c, 26d, 26e, 26f).
5. The method according to any of the foregoing claims or according to the preamble to
claim 1, characterized in that the washing liquid spraying means (26a, 26b, 26c, 26d,
26e, 26f) are moved in a direction perpendicular to the path of the jet of washing
liquid of the corresponding face (14a, 14b, 14c, 14d, 14e, 14f) and parallel to each
face (14a, 14b, 14c, 14d, 14e, 14f).
6. The method according to any of the foregoing claims or according to the preamble to
claim 1, characterized in that the washing liquid spraying means (26a, 26b, 26c, 26d,
26e, 26f) are moved in a direction perpendicular to the corresponding face (14a, 14b,
14c, 14d, 14e, 14f).
7. An apparatus (10) for washing parts (12), especially parts (12) having cavities (16)
extending inwards from their outer surfaces (14a, 14b, 14c, 14d, 14e, 14f) and comprising
a base (20) that supports at least one part (12), means (26a, 26b, 26c, 26d, 26e,
26f) for spraying a liquid to wash a corresponding surface (14a, 14b, 14c, 14d, 14e,
14f) of the part (12), means for moving the part (12) and the washing liquid spraying
means (26a, 26b, 26c, 26d, 26e, 26f) relative to each other in such a way as to wash
the corresponding surface (14a, 14b, 14c, 14d, 14e, 14f) of the part (12), the apparatus
being characterized in that it comprises means for controlling the movement of the
part (12) relative to the washing liquid spraying means (26a, 26b, 26c, 26d, 26e,
26f) in such a way as to produce movements in steps of predetermined length so that
the washing liquid is sprayed into the cavities (16) in the corresponding surfaces
(14a, 14b, 14c, 14d, 14e, 14f).
8. The apparatus according to claim 7, characterized in that the washing liquid spraying
means (26a, 26b, 26c, 26d, 26e, 26f) used to wash the corresponding surfaces (14a,
14b, 14c, 14d, 14e, 14f) of the part (12) comprise a plurality of nozzles (28), each
of which sprays a jet (30), of washing liquid, said nozzles (28) being aligned with
each other in such a way that the jets (30) sprayed by them strike the part (12) to
be washed along a corresponding band of the part (12) itself.
9. The apparatus according to claim 7 or 8, characterized in that it comprises washing
liquid spraying means (26a, 26b, 26c, 26d) to wash the longitudinal surfaces of the
part (12) and washing liquid spraying means (26e, 26f) to wash the transversal surfaces
of the part (12).
10. The apparatus according to any of the foregoing claims from 7 to 9, characterized
in that the means for obtaining the relative movement between the part (12) to be
washed and the washing liquid spraying means (26a, 26b, 26c, 26d) are such as to move
the part (12).
11. The apparatus according to any of the foregoing claims from 7 to 10, characterized
in that the means for obtaining the relative movement between the part (12) to be
washed and the washing liquid spraying means (26e, 26f) are such as to move the washing
liquid spraying means (26e, 26f) relative to the part (12).
12. The apparatus according to any of the foregoing claims from 7 to 11, characterized
in that the control means comprise sensor means (36, 38) designed to detect the relative
position of the part (12) and/or of the washing liquid spraying means (26a, 26b, 26c,
26d, 26e, 26f) and electronic processing means (40) which generate a signal in response
to the signal from the sensor means (36, 38) in order to move the part (12) and/or
the washing liquid spraying means (26a, 26b, 26c, 26d, 26e, 26f) relative to each
other in steps of predetermined length.
13. The apparatus according to any of the foregoing claims from 7 to 12 or according to
the preamble to claim 7, characterized in that it comprises washing liquid spraying
elements (26a, 26b, 26c, 26d, 26e, 26f) each designed to wash a corresponding face
(14a, 14b, 14c, 14d, 14e, 14f) of the part (12); and in that it further comprises
means for selectively feeding the washing liquid to one or to a predetermined number
of said washing liquid spraying elements (26a, 26b, 26c, 26d, 26e, 26f).
14. The apparatus according to claim 13, characterized in that the means for selectively
feeding the washing liquid to the spraying means (26a, 26b, 26c, 26d, 26e, 26f) comprise
means (42) for pumping the liquid from the tank (13) of the washing liquid (15), means
(44) for distributing the flow of washing liquid to the spraying means (26a, 26b,
26c, 26d, 26e, 26f) and means (40) for controlling said liquid flow distributing means
(44).
15. The apparatus according to any of the foregoing claims from 7 to 14 or according to
the preamble to claim 7, characterized in that it comprises means (M26a, M26b, M26c
M26d, M26e, M26f) designed to move the washing liquid spraying means (26a, 26b, 26c,
26d, 26e, 26f) in a direction parallel to the corresponding faces (14a, 14b, 14c,
14d, 14e, 14f) and perpendicular to the path of the jet of washing liquid of the corresponding
faces (14a, 14b, 14c, 14d, 14e, 14f).
16. The apparatus according to any of the foregoing claims from 7 to 15 or according to
the preamble to claim 7, characterized in that it comprises means (D26a, D26b, D26c
D26d, D26e, D26f) designed to move the washing liquid spraying means (26a, 26b, 26c,
26d, 26e, 26f) in a direction perpendicular to the corresponding faces (14a, 14b,
14c, 14d, 14e, 14f).