US2217920A

US2217920A - Screen hook strip

Info

Publication number: US2217920A
Application number: US242785A
Authority: US
Inventors: Alexander J Roubal
Original assignee: Allis Chalmers Corp
Current assignee: Allis Chalmers Corp
Priority date: 1938-11-28
Filing date: 1938-11-28
Publication date: 1940-10-15
Anticipated expiration: 1957-10-15

Description

Oct. l5, 1940. A J- 'RQUBAL 2,217,920

SCREEN HOOK STRIP Filed NOV. 28, 1938 Patented Oct. 15, 1940 UNITED STATES 2,217,920 v SCREEN nooxs'rmr Alexander J. Roubal, wauwatosahwis., assignor to Allis-Chalmers Manufacturing Company,

Milwaukee, Wis., a

corporation of Delaware Application November 28, 1938, Serial No. 242,785

Claims.

This invention pertains to a screen fastener and relates particularly to end hooks used on the edges of sections of woven screen cloth utilized in vibrating and other screens.

It is an object of this .invention to provide a construction of hook strip which is rugged and easy to manufacture, and which retains the woven screen cloth uniformly along the entire edge thereof, making effective vibration of the entire screen cloth possible.

The invention is illustrated by the preferred modifications shown in the drawing appended hereto, wherein:

Fig. 1 shows a screen assembly embodying end strips in accordance with the invention;

Figs. 2, 3, and 4 show various steps in the process of assembling a hook strip in accordance with the invention; and

Figs. 5 and 6 show other modifications of the strip fasten-er construction.

Referring to the drawing in more detail, Fig. 1 shows a screen assembly of the type disclosed in U. S. patent to Lincoln 1,999,769, April 30, 1935.

u This comprises generally a screen section Ill reinforced and supported at its side edges by means of end books II which are supported in place by lever plates I2 fastened to side walls I4 of the screen body by means of screws I3. This general screen assembly forms no part of the present invention and is briey described merely to indicate the manner of utilizing the screen hook of the present invention.

To assemble the preferred form of end hook in accordance with this invention, the woven screen u section III is superimposed on the wide outer stripy I6, which is usually made of sheet metal, the outer edges of the screen and strip substantially coinciding. Then the inner strip I1 is super-imposed on screen cloth I0, the outer edge of strip I1 being spaced inwardly from the outer edges of strip I6 and screen cloth I0, as shown in Fig. 2. The next step is to bend the outer ends of screen section Ill and strip I6 over the outer edge of strip 45 II to form a U as shown at I61 in Fig. 3. Then it is merely necessary to bend both strips and screen through an angle of over 90 at some point I8, as shown in Fig. 4, in order to obtain the nished screen fastener or end hook.

It will be noted that the first bent strip, as shown in Fig. 3, serves to fasten the screen 4cloth tightly between strips I6 and I1; while the second bent strip serves to stretch and intimately clamp the screen cloth uniformly along the full length thereof.

55 The construction shown in Fig. 5 is somewhat similar to that shown in Fig. 4 except that the outer strip I9, instead of terminating evenly with the edge of the screen cloth, extends in a U around the edge of the screen, as shown at 23, and forms a reverse U bend around the edge of strip I1, overlapping strip I 1 at 24. The particular advantage of this modification over that of Fig. 4 is that strip I9 covers the edge of strip I1, preventing any possible cutting or weakening of the screen cloth by contact with this edge, which may srntimes be sharp enough to damage the screen c o The construction of Fig. 6 is also built around a. strip I1, as in Figs. 4 and 5. The screen I0 is bent over one edge of this strip, as in the constructions described above, but a wider margin is shown between the edge of the screen cloth and the free edge of strip Il. The other strip 25 is laid over strip Il, and bent over the free edge of said strip, terminating at 26. It will be seen that this construction is generally similar to that of Fig. 4, but the strip 25 diiers from strip I'I in having its major portion inside the angle formed by the two legs of strip I'I rather than on the outside thereof. This construction is particularly adaptable for coarse screen cloth, where great tension is applied thereto and it is desired to have more than one thickness of metal between the screen cloth and a fastening means such as plate I2.

It is not desired to limit the invention to the exact details herein shown and described, as modiilcations within the scope of the invention will occur to those skilled in the art.

It is claimed and desired to secure by Letters Patent:

1. An end hook for a section of screen cloth comprising a long integral strip having two longitudinal sections arranged at an angle of substantially less than 90, a woven wire cloth having one straight edge extending beyond an edge of said strip and bent over said edge in U-shape, a second long strip having an edge overlying said bent over edge of said wire cloth, an intermediate portion bent over saidl bent over edge of said rst strip to form a U, and another portion comprising the other edge of said second strip parallel to the other section of said rst strip.

2. An end hook for a rectangular screensection comprising a first integral long strip having two longitudinal legs arranged at an angle of substantially less than 90, a second strip having one longitudinal leg parallel to one leg of said rst strip and coextensive therewith and -a second longitudinal leg bent into U-shape and substantially parallel to the other leg of said rst strip, a woven screen cloth arranged between seid ilrst legs of said strips and having an edge within said U- shaped portion of said second strip, said U- shaped portion of said second strip and the screen cloth therein being further bent around the edge of said other leg of said first strip.

3. An end hook for a rectangular screen cloth section comprising'a straight long strip having two longitudinal legs arranged at an acute angle, a rectangular screen cloth having one longitudinal edge contacting the outer surface of said strip and forming a U around one edge thereof, and a second straight long strip forming a U and overlying said U-shaped portion ofthe screen edge.

4. An end hook for a screen cloth comprising a first strip having twolegs making an acute angle with each other, a rectangular screen cloth having one rectilinear edge contacting the outer surfaces of said strip and forming a U around one edge thereof, and a second strip having two legs parallel to and Within said ilrst strip. one leg of said second strip being bent over said U-shaped screen cloth, said nrst and second strips clam ing said screen cloth between them.

5. An end hook tor a section of screen cloth having oppositely disposed substantially straight edges comprising a long narrow strip spaced from one of said edges and being arranged with its long axis parallel to said edge. said edge ot said screen cloth being bent over to overlie said 10118 narrow strip, a wider strip overlying said bent over screen cloth edge and bent back to protect the side of the screen cloth opposite to that covered by said tlrst strip, both strips and the screen cloth therebetween being bent through an angie substantially greater than 90 to form an end hook.

ALEXANDER J. ROUBAL.