SEAL CONSTRUCTION FOR A DOUGH ROLLER

Abstract: Seal construction for the prevention of dough leakages between the main rolls (2) and the lateral ends (3) in a dough roller, which said construction comprises members (4) provided at both ends of the dough roller and scraping the end faces of the main rolls (2). The invention is characterized in that the members (4) are placed right at the nip (6) between the main rolls (2).

Description: Seal construction for a dough roller The subject of the present invention is a seal construction for the prevention of leakages of dough between the main rolls and the lateral ends in a dough roller, which said construction comprises members provided at both ends of the dough roller and scraping the end faces of the main rolls. In prior art, in apparatuses that roll dough into a mat, a seal construction has been used commonly that is based on a preset play between the main rolls and the lateral ends. The lateral ends are the plane side walls that define the transverse length of the space between the dough funnel and the main rolls. It is a drawback of such a prior-art seal solution that, by the effect of factors dependent on time and on dough types, abrasion and corrosion tend to increase the preset play. Increased leakages result. In the course of time, the leakage mix is gathered as deposits in some part of the roller unit, from where it falls down occasionally as "clots" onto the belt and ends up at the bottom of the mat that is _eing rolled. A problem is the fact that this cementlike deposit no longer consists of baking-quality dough, but it lowers the quality of the final products. Solutions for this problem have been sought for both by manufacturers of machinery and by bakers, yet, without success. It has not been possible to compensate for the abrasion and corrosion, and from time to time it has been necessary to subject the machines to a costly and time-consuming overhaul. In the German published Patent Application No. 27 41 294 a seal construction for a dough roller is described wherein both ends of the apparatus are pro- vided with members that scrape the- end faces of the main rolls, viz. a stationary doctor rib, which, being jointly operative with the end faces of the main rolls, is arranged so that it returns any dough that penetrates in between the end face and the side wall back into the dough funnel along an arcuate path formed by the doctor rib and passing around the axis of the roll. Thus, the dough is allowed to revolve about one revolution along with the main rolls, being pressed between the end faces of the main rolls and the frame part of the doctor member, before it is passed back into the dough funnel. It is a drawback of this prior-art construction that the baking quality of the dough, which has been subjected to high pressure and to a grinding movement, has been lost, i.e. the said dough is "dead" and does not rise on baking. Thus, the dead dough residues recirculated to the dough have a deteriorating effect on the quality of the final product baked out of this dough. The object of the present invention is to eliminate the above problems and drawbacks, which has been achieved by using a seal construction which is characterized in that the members are placed right at the nip between the main rolls, i.e. immediately under¬ neath the location at which the dough is usually ex¬ truded to some extent. By means of this solution, it is possible to prevent penetration of dough between the end faces of the main rolls and the lateral ends co - pletely. The quality of the bread products produced in rollers provided with a member or doctor in accordance with the invention is improved significantly, and the cost of maintenance of the equipment is reduced consider¬ ably, because the servicing intervals of the equipment become decisively longer. The further characteristics of the invention come out from the attached claims 1 to 4. In the following, the invention will be de¬ scribed in more detail with reference to the accompanying drawing, wherein - Figure 1 shows an example of a seal construc¬ tion in accordance with the invention seen from the side of the dough roller, and Figure 2 shows an apparatus in accordance with Fig. 1 viewed from above, with the dough funnel removed. A typical dough roller includes two main rolls 2 jointly operative with each other and a dough funnel 1 provided above the rolls. The transverse length of the space between the dough funnel 1 and the main rolls 2 is defined by side walls or lateral ends 3. The dough roller operates so that dough introduced into the dough funnel 1 is rolled in the nip 6 between the main rolls 2 revolving in the direction indicated by the arrows into a dough mat, which is passed to the following stage of treatment preferably by means of a conveyor belt running underneath the main rolls 2. Any amount of dough leaking into the gaps between the ends of the main rolls 2 and the lateral ends 3 is scraped off immediately by means of doctors 4 in accordance with the invention, so that the leakage of dough cannot be gathered as deposits in any part of the roller unit. The doctor 4 is preferably V-shaped and placed in such a way that its tip 4a is placed facing the nip 6 between the main rolls 2. Thereat the shape of the doctor 4 contributes to the fact that any dough attempt¬ ing to penetrate into the gap between the main rolls 2 and the lateral ends 3 is immediately guided back into the nip 6 between the main rolls 2. In view of guaranteeing the operability of the apparatus and compensating for wear, the doctor 4 is preferably spring-loaded by means of a compression spring 5. The compression force of the doctor 4 is easily adjustable by means of a simple regulating device, such as an adjusting screw. Thus, owing to this solution, the compression force of the doctor 4 remains at the de¬ sired level in spite of thermal expansions or con- tractions of the main rolls 2. _ The doctor 4 is preferably made of a wear-proof and corrosion-proof material, such as tin bronze.

Claims: WHAT IS CLAIMED IS: 1. Seal construction for the prevention of leakages of dough between the main rolls (2) and the lateral ends (3) in a dough roller, which said con¬ struction comprises members (4) provided at both ends of the dough roller and scraping the end faces of the main rolls (2), c h a r a c t e r i z e d in that the members (4) are placed right at the nip (6) between the main rolls (2) . 2. Seal construction as claimed in claim 1 , c h a r a c t e r i z e d in that the member (4) is substantially V-shaped and its tip (4a) is placed facing the nip (6) . 3. Seal construction as claimed in claim 2, c h a r a c t e r i z e d in that the member (4) is spring-loaded (5) and its compression force is adjust¬ able by means of an adjusting screw. 4. Seal construction as claimed in claim 3, c h a r a c t e r i z e d in that the member (4) is made of tin bronze.

Inventors: LAMMELA MARTTI, LAMMELA, MARTTI
Applicants: HYDROVOIMA OY
Application year: 1987
Main classification: A21C3
IPC codes: A21C3