A DEVICE FOR PREPARING PUTTY AND SIMILAR MASSES

Abstract: A device for tempering and homogenizing viscous masses, particularly putty, and incorporating a combined heat exchanger and homogeniser (10), having a tubular part (12) through which the putty under pressure and tempering is caused to pass. In said tubular part (12) is provided a guiding device (16) designed compulsory to give the putty a plurality of direction changes relative to the tubular part (12). The guiding device (16) incorporates at least a first helical heat exchanger tube (17) arranged around a centrally disposed, second heat exchanger tube (18).

Description: A DEVICE FOR PREPARING PUTTY AND SIMILAR MASSES The present invention refers to a device for tempering and homo¬ genizing viscous masses, particularly putty, and incorporating a combined heat exchanger and homogeniser, having a tubular part through which the putty under pressure and tempering is caused to pass, and in which tubular part is provided a guiding device designed compulsory to give the putty a plurality of direction changes relative to the tubular part. BACKGROUND OF THE INVENTION When producing objects consisting of bigger units, which shall be sealingly interconnected, sealing agents are widely used in the form of especially developed qualities of putty. For this purpose it has been developed such putties having a big ability of pene¬ trating into even very small spaces and joints and thereby forming a continuous sealing layer being resistant to chemical as well as mechanical influence. It thereby has been possible to reach considerable rationalization profits. At manufacture e.g. of car bodies it thus has been possible to abandon the method of tight welding entire joints and instead to use spot welding for interconnecting the car body parts, whereupon especial putty under high pressure is pressed into the joints. The requirements on such a putty are of course very big. The viscosity at - he moment of applic .ticn as well aε the homogenity of the materiel are thereby of crucial importance. For iε reason, as an example, in the just mentioned application tne permitted temperature tolerance of the putty thus is ± 0. °C only. It certainly has been possible, fairly to hold such a temperature, but the problem has been to obtain therebeside a sufficient homogenity in combination with a rational manufacture. In a known device the putty is pumped from a drum and is pressed through a heated pipe. Thereby however will occur the phenomenon that putty, due to the friction, as a thin surface layer will adhere to the inner envelope surface of the pipe and become immobile. This layer will solidify and build up radially inwards thus that the flow area gradually will be reduced and finally becomes so small that the process must be interrupted and a time- wasting cleaning operation must be begun. Another drawback is that the components of the putty on its path from the drum to the putty gun are separated, which refers particularly to bonding agents therein, which means that some putty portions will contain too much and other too little bonding agent. In DE-A-2364500 is shown a combined heat exchanger and static mixer for photographic emulsions, which shall have a temperature between 35° and 40 C C. The device consists of an outer tube and an inner pipe extending axially therethrough, which inner pipe has external helically extending segments. The heating medium flows through the inner pipe, whereas the emulsion passes between the inner pipe and the outer tube and by said segments is given a helical path. A temperature tolerance as low as 0.5°C, which is permitted for putty is considered to be difficult to maintain with this device. PURPOSE AND MOST ESSENTIAL FEATURES OF THE INVENTION The purpose of ".he invention theref re is to provide a " imple an≤ efficient plant, which requires a r.inimum of maintenance, ar.c which guarantees a homogenous mass of putty of ccrrec- temperature. For performing this and other purposes the invention has been given the features appearing in the claims. DESCRIPTION OF THE DRAWINGS In the accompanying drawings are shown some embodiments as examples of the invention. Thereby Fig. 1 is a longitudinal section through a device according to the invention, and Fig. 2 is a corresponding longitudinal section through another embodiment of the invention. DESCRIPTION OF THE EMBODIMENTS The homogeniser 10 according to fig. 1 consists of an outer tubular casing 11, which is closed at its ends, and through which extends an inner tubular part 12. The casing 11 at one end has an inlet 13 and at the opposite end an outlet 14 for the tempering fluid, e.g. water. Between the inner tubular part 12 and the outer casing 11 is provided a guiding member 15, which gives the water a helical movement in its path through the tempering zone. In the tubular part 12 is inserted a guiding member designated 16 and consisting of a first helical heat exchanger tube 17 provided around a centrally disposed second heat exchanger tube 18 extending axially through the tubular part 12. A helical, third heat exchanger tube 19 is further provided around the central heat exchanger tube 18 and has opposed pitch as compared to the first heat exchanger tube 17. Tempered water is supplied to all heat exchanger tubes, whereby according to Fig. 1 the central tube 18 is supplied with water in opposite direction to that of the two helical tubes 17 and 19. The tubular par 12 at its ends is closed by end plat s 20 and 21, which are detachably attached to the part 12, e.g. y mean? of screws. The ends of the heat exchanger tubes 17, 18, 19 are led through sealed off openings in the end plates and the enc portions situated outside the end plates have external threads and are by means of nuts 22 detachably attached to the associated extension tubes 23, 24 and 25 resp. Cleaning of the device is facilitated hereby, as the heat exchanger tubes 17, 18, 19 may be disconnected and taken out from the tubular part 12. The tubular part 12 has at one of its ends an inlet 26, through which putty under high pressure is introduced in the tubular part 12 in order thereupon to leave it through an outlet 27 at the opposite end, from which the putty passes to one or more not shown nozzles or the like for application of the putty. The putty, which, via the tempering fluid flowing on one hand through the tubes 17, 18, 19 and on the other hand inside the casing 11, is maintained at the prescribed temperature, is pressed through the homogeniser at a pressure, which at the application for manufacture of car bodies here described amounts to 350 bars. The mass of putty is thereby urged to make a number of direction changes against the helical heat exchanger tubes 17, 19 in contact with the outside of the central heat exchanger tube 18 and against the inner side of the tubular part 12, which is likewise tempered by the tempering fluid. It thus is obvious that the mass will get an even heat supply at the same time as an efficient admixing is obtained and its tendency of adhering to the inner surface the tubular part 12 is reduced. The embodiment shown in Fig. 2 differs from the one shown in Fig. 1 in that the two helical heat exchanger tubes 17 and 19 at the outlet end of the device are bent in towards the central heat exchanger tube 18 and opens therein. The tempering fluid hereby after having pass-.d through the helic-.l heat exchanger t;:beε 17, 19 is caused to enter the central heat exchanger tube 15 and to leave it at the opposite end thereof. The tubular 12 has only at one of its ends, the inlet end, a detachably attached end plate 20, whereby it is possible, by unbolting said end plate 20, to remove the heat exchanger tubes 17, 18 and 19 for cleaning the device. The invention is of course not limited to embodiments shown but a plurality of modifications is possible within the scope of the claims.

Claims: CLAIMS 1. A device for tempering and homogenizing viscous masses, particularly putty, and incorporating a combined heat exchanger and homogeniser (10), having a tubular part (12) through which the putty under pressure and tempering is caused to pass, and in which tubular part (12) is provided a guiding device (16) designed compulsory to give the putty a plurality of direction changes relative to the tubular part (12), c h a r a c t e r i z e d t h e r e i n, that the guiding device (16) incorporates at least a first helical heat exchanger tube (17) arranged around a centrally disposed, second heat exchanger tube (18). 2. A device as claimed in claim 1, c h a r a c t e r i z e d t h e r e i n, that the guiding device also incorporates a third helical heat exchanger tube (19) arranged around said central second heat exchanger tube (18) and having the opposite pitch as compared to said first heat exchanger tube (17). 3. A device as claimed in claim 1 or 2, c h a r a c t e r i z e d t h e r e i n, that tempered fluid is caused to flow through the central heat exchanger tube (18) in opposite direction as compared to that of the helical tubes (tube) (17,19). 4. A device as claimed in claim 1, 2 or 3, c h a r a c t e r i z e d t h e r e i n, that the tubular part (12) is surrounded by a casing (11) through which tempered fluid is intended to flow, and that in the annular casing are provided guiding means (15) intended to guide the water in a serpentine or helical path. 5. A device as claimed in one or more of the preceeding claims, c h a r a c t e r i z e d t h e r e i n, that said guiding device (16) is designed as a detachable insert for the tubular part (12). 6. A device as claimed in claim 5, c h a r a c t e r i z e d t h e r e i n, that the tubular part (12) at least at one end is closed by a detachably attached end plate (20, 21), through which said heat exchanger tubes (17,18,19) are led. 7. A device as claimed in claim 6, c h a r a c t e r i z e d t h e r e i n, that the helical heat exchanger tubes (tube) (17, 19) at the outlet end of the device are/is bent in towards and opens in the central heat exchanger tube (18), whereby the tempered fluid after leaving the helical heat exchanger tubes (tube) is caused to flow back in opposite direction through the central heat exchanger tube (18).

Inventors: TILLY LEIF, TILLY, LEIF
Applicants: TILLY S ROER AB, TILLY'S ROER AB
Application year: 1988
Main classification: B01F3
IPC codes: B01F5, B01F15, F28D7