FR2593245A1 - PUMPING UNIT FOR AN INSTALLATION FOR THE APPLICATION OF COATINGS - Google Patents

Abstract

The invention relates to techniques for applying coatings, in particular painting. The pumping unit forming the subject of the invention is characterized in particular in that the internal cavity of the bellows 12 placed in the body 11 'communicates with the delivery 19 and suction 18 pipes by means of the delivery valves. 15 and suction 14, respectively, the cavity 17 formed between the outer surface of the bellows 12 and the inner surface of the body 11 'being filled with a compensating fluid consisting of a filling liquid, while in the ends of the control 7 are provided with chambers 20 for collecting filling liquid leaks. The invention can be used advantageously in the chemical and petroleum industries. (CF DRAWING IN BOPI)

Description

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  The present invention relates to equipment for the application of coatings, in particular for painting, on

  objects, in particular according to the method of pulveri-

  airless system ("Hydra-Spray"), and particularly relates to a pumping unit for an installation for the application of

coating.

  The invention can be used advantageously in

  the chemical and petroleum industries, for the transvase-

  pumped and for high pressure delivery

  aggressive liquids and contaminated liquids.

  A pumping unit used in installations for the application of paint coatings is known

  following an airless spray method (Eine technis-

  Hokumentation des Hauses I. Wagner GmbH Friedrichshofen Problemlosungen fur die industrial Oberflachenbeschichtung, page 7) comprising a reciprocating motion control consisting of a body housing a piston and a rod, a

  hydraulic pump attached to one end of the com-

  mande, constituted by a body in which is placed a

  plunger connected to the rod of the control, a device for

  and two valves: one of repression and the other of

piration.

  In the known pumping group,

  vaser can enter the space between the plunger and the body of the hydraulic pump, resulting in

  rapid wear of said parts and the sealing device.

  A paint pumping unit is known (high-pressure paint units 2600H and 7000H, Notice, Vilniuskoie objedinenie stroitelnootdelochnykh mashin (USSR), 1978, page 14) comprising an electric motor whose shaft carries an eccentric in connection with the piston. ,

  actuated by a spring, a hydraulic pump, a mem-

  brane, suction and discharge valves, an intake filter connected to the suction pipe of the group

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  and a paint sprayer, communicated by a flexible hose with the discharge pipe of the group. This known group comprises a large number of membrane movement cycles (1200 cycles per minute), which is explained by the short stroke of the membrane and the

  need to move a sufficient amount of paint.

  This causes the rapid rupture of the membrane, due to the

  Tigue. A pumping unit is known for mounting deep well liquids (USSR Ser. Certificate No. 580351, F 04B, 1977), comprising a reciprocating motion control, at least two bodies disposed at opposite ends. of the control, a bellows placed in each body so as to form a cavity between its outer surface and the inner surface of the body, the inner cavity of the bellows placed in the first body being in communication with the discharge and suction pipes by via discharge and suction valves, respectively,

  and the cavity between the outer surface of the

  flounder and the inner surface of the first body being replaced

  fold of a compensator constituted by a filling liquid

wise.

  In this known pumping group, pauses take place

  in the supply of the product to be decanted during the

  which is not permissible when said product is a paint. The pumping group has a number

  large number of elements connected in series, which complicates

  its construction, undermines its reliability and makes it

more expensive.

  It was therefore proposed to create a pumping group

  page for an installation for the application of coating-

  ments, which would make it possible to carry out

  of the liquid to be poured under high pressure to a

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  receiving apparatus while avoiding contact between the

  pumped surface and the friction surfaces of the pumping unit parts, thus ensuring a significant simplification of its construction and a considerable extension of its service life.

  This problem is solved by the fact that the pumping group

  page for an installation for the application of coatings, comprising a reciprocating movement control, at least two bodies disposed at opposite ends of the control, a bellows placed in each body so that its outer surface forms a cavity with the surface

  inside the body, the inner cavity of the bellows

  in the first body being in communication with the

  discharge and suction lines through the

  of discharge and suction valves, respec-

  the cavity between the outer surface of the

  flounder and the inner surface of the first body being filled

  a compensating fluid consisting of a filling liquid

  is characterized, according to the invention, by the fact that

  Inner life of the bellows placed in the second body

  communicates with the discharge and suction lines

  by means of discharge and suction valves, respectively, and the cavity between the outer surface of the bellows and the inner surface

  of the second body is filled with compensating fluid

  by a filling liquid, and in each end

  a chamber for collecting the filling liquid leaks and connected via a check valve to the cavity between the outer surface of the bellows and the

  inner surface of the body at the opposite end

asked of the order.

  Such a design of the pumping unit ensures a sufficiently long stroke of the rod and a

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  fewer cycles per minute, as well as

  sea the contact between the pumped paint and the moving parts. The harmful phenomenon of compensating fluid leakage in the presence of cross-links: leak collection chamber - cavity between the outer surface of the bellows and the inner surface of the body, is used to ensure lubrication

  abundant of the moving stem. All this makes it possible

  Maintain the life of the pumping group in comparison

  known plunger and diaphragm pumping units.

  The claimed construction of the pumping group

  does not require the use of expensive materials or their

  finishing, which reduces the cost of manufacturing

  tion. The invention will be better understood and other purposes, details and advantages thereof will become more apparent in the

  light of the following explanatory description of a

  embodiment given solely by way of non-limiting example, with references to the appended nonlimiting drawings in which:

  FIG. 1 represents an installation for the application

  application of paint coatings according to the method of airless spraying, according to the invention (overview); FIG. 2 represents an embodiment of the

  pumping unit according to the invention (longitudinal section

  nal); FIG. 3 represents the set A of FIG.

2 (on an enlarged scale).

  The concrete example concerns the pumping group u-

  used in a coating application plant

  of paint using the airless spray method.

  The installation includes a pumping group 1

  (FIG. 1) mounted on a carriage 2, a sprayer 3 connected to

  corded by a pipe 4 to the discharge pipe of the

2593245

  pumping group 1, a paint filter 5 connected by a

  pipe 6 to the suction pipe of the pumping group

  ge. The pumping unit 1 comprises a movement control 7 in-venetated in the form of a body 8 housing a piston 9 and a rod 10, at least two bodies 11, disposed at the opposite ends of the control 7 and

each housing a bellows 12.

  The bellows 12 is connected by its terminal end

  at the stem 10, and by its open end, to the body

  11 or 11 'via a conical element 13 (FIG.

  3) and a cap nut 13 '. The conical element 13

  at the same time serves as a flap box in which

  are mounted a suction valve 14 and a check valve

repression 15.

  The bellows 12 (FIG. 2) has an internal cavity

  16, while its outer surface and

  inner face of the body 11 or 11 'form between them a cavity

  17 filled with a compensating fluid consisting of a

filling liquid.

  The inner cavity 16 of each bellows 12 comprises

  provided with a suction pipe 18 by the corresponding suction valve 14, and with a pipe of

  discharge 19, by the discharge valve 15 correspon-

ing.

  In the ends of the control 7 are formed grooves forming chambers 20 for collecting liquid leaks, each of these chambers being

  arranged in one end of the control 7 and

  connected, via a coupling pipe 21 and a check valve 22, to the cavity 17 of the body located at the end

opposite of the order 7.

  In each end of the control 7 is mounted externally a guide sleeve 23 (Figure 3), in which the rod 10 of the control 7 (Figure 2), and are provided two sealing devices, the first

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  comprises a lining 24 (FIG. 3) and a safety ring

  25, and the second, a ring 26 and two rings

  27. The body 11 or 11 is fixed to the end face of the body 8 of the control 7 by threaded fixing means 28. The bellows 12 is fixed by its blind end to the

  rod 10 via a fastener 29.

  The pumping group for an installation for

  coating application works as follows.

  The paint filter 5 (FIG. 1) is immersed in

  the paint container (not shown) and it

  the pump group i which sends the paint under

  pressure through the hose in the pulverizer

  Sator 3 for painting the different objects.

  With the pumping group 1 switched on, the pis-

  your 9 performs, together with the rod 10 of the control

  of 7, a movement back and forth, stretching a bellows 12 and compressing the other. A depression is created in the cavity 16 of the bellows 12 stretched and the product to be pumped (the paint) enters through the filter 5 and the suction valve 14. In the cavity 16 of the bellows 12 compressed, a high pressure is creates and is transmitted, by means of the compensating fluid filling the cavity 17, to the walls of the body 11 or 11 ', and the paint enters the discharge pipe 19

  passing through the discharge valve 15. The walls of the

  flounder 12 only suffer from compression forces

  regular metric, which guarantees its smooth operation.

  ble and its long life. The compensating fluid

  titué by the liquid filling the cavity 17 undergoes high pressure and enters the space between the rod 10 and the sleeve 23 (Figure 3), by lubricating abundantly the

  indicated parts and ensures their reliable and prolonged service.

  Then the compensating fluid enters through the first device

  sif (seal 24 and safety ring 25) in the chamber 20 for collecting leaks, and through the pipe 21 and the check valve 22, in the cavity 17 of the body 11 or 11 'opposite, where the pressure is more weak than the atmospheric pressure. The ring 26 and the two safety rings 27 prevent the compensating fluid from penetrating

  in the body cavity 8 of the control 7.

  The cycle is repeated during the return of the piston 9

  and the rod 10. The paint is flowed in a manner

  in the discharge pipe 19 by the two bellows alternately and the penetrating compensator by

  the games circulate between the opposing bodies 11, 11 ', in

  abundant lubrication of the friction surfaces of the rod 10, the bushing 23, the packing 24 and the ring 25, which guarantees their reliable operation

and long lasting.

  Using a minimal number of sets

  in the pumping group, the introduction of the second

  flet, the realization of leak collection chambers

  between the sealing devices and their connection to the

  17 greatly simplify the construction of the pumping unit and considerably increase its duration.

of life.

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R E V E N D I CA TION

  Pumping unit for an installation for the appli-

  application of coatings, of the type comprising a control (7) of displacement back and forth, at least two bodies

  (11, 11 ') each located at one of the two opposite ends

  a bellows (12) placed in each body (11, 11 ') so that its outer surface and the inner surface of the body (11, 11') form between them a cavity (17). ), the internal cavity of the bellows (12) placed in the body (11) being in communication with the discharge (19) and suction (18) pipes via

  via discharge valves (15) and vacuum

  ration (14), respectively, and the cavity (17) between

  the outer surface of the bellows (12) and the inner surface

  upper body (11) being filled with a compensating fluid constituted by a filling liquid, characterized in that the internal cavity of the bellows (12) placed in the body (11 ') communicates with the discharge pipes (19) and suction (18) via the discharge (15) and suction (14) valves, respectively,

  the cavity (17) formed between the outer surface of the

  flet (12) and the inner surface of the body (11 ') being filled with a compensating fluid constituted by a liquid

  filling, while in the ends of the com-

  Mande (7) are provided chambers (20) collection

  leaks of filling liquid, each of these chambers

  made in one end of the control (7)

  and being connected, via a check valve

  turn (22) to the cavity (17) formed between the outer surface

  bellows (12) and the inner surface of the body

  (11 or 11 ') placed at the opposite end of the control (7).