US1998880A - Cloth plate for sewing machines - Google Patents

Description

April 23, 935. R. MACKAY, JR

CLOTH PLATE FOR SEWING MACHINES Filed Jan. 3C)l 1955 (u mi l f Patented Apr. 23, 1935 UNITED STATES PATENT oFFIcE CLOTH PLATE FOR SEWING MACHINES Richard Mackay, Jr., Chicago, Ill., assignor to Union Special Machine Company, Chicago, Ill., a corporation of Illinois Application January 30, 1933, serial No. 654.346

3 Claims.

The invention relates to new and useful im# provements in a cover plate for sewing machines, and more particularly to the cloth plate on which thejfabric is supported during stitching.

v An object ofthe invention is to provide a cover plate for the actuating-parts of a sewing machine which is so constructed that thevibrati'ons set up Within the metal parts of the cover plate are absorbedy or dampened fand reduced so as to avoid objectionable noise incident to the operation of the machine.

In the drawing:-

Figure 1 is a View partly in end elevation and vpartly in section showing a sewing machine having the improved cloth plate applied thereto, and

Fig. 2 is a perspective View of the cloth plate detached from the machine and as viewed from the inner side thereof.

The stitching and feeding mechanisms of sewing machines havebeen developed to' a point so that the parts may be operated for producing stitches at the rate of from four to nve thousand stitches per minute. The fabric is moved intermittently, coming to aA stop between stitches. The needle is reciprocated and there are many parts in the machine which move back and forth during the operation thereof. Each part partakes of its back and forth movement for each stitch cycle. These rapidly operating parts create vibrations in the frame structure and in the cover plates mounted thereon which produces an objectionable noise. The purpose of the present invention is to provide a cover plate structure wherein the vibrations transmitted thereto by the operating parts in the machine are so absorbed or dampened that the objectionable noise is avoided. The invention as illustrated, is shown as applied to a cloth plate used on a machine of the type described in the patent to Christensen & Zeier No. 1,751,508, granted March 25, 1930. In this patent there is a cloth plate provided with a depending apron for housing the parts beneath the same. In the machine illustrated in the drawing, the cloth plate applied to this type of machine is shown as formed of sheet metal and is pivoted so that it may be moved to uncover the actuating parts beneath the same. In carrying out the invention, the cloth plate is provided on its under face throughout substantially the entire extent thereof, and also the apron on its inner face, with a lining of cork which is cemented to the cloth plate so that it becomes rigid therewith and must necessarily partake of the vibrations imparted to the cloth plate. It is well known that cork does not partake of sound creating vibrations, and therefore, when x'ed to the cloth plate, it will absorber dampen the vibrations in the metal parts, thus `reducing the same so that objectionable noise is'avoided. 1.Y Referring more in v'detail tothe drawing, the 5 invention is shown as' applied to a sewing kmachine. whichincludes a supporting base I having theoverhanging arm 2 .in winch a rneedle bar 3 reciprocates carrying a needle 4. This machine is of the type shown in the Christensen & Zeier 10 patent referred to above, and detail description of the machine is not thought necessary.

Mounted on the bed is a supporting bracket 5, and the cloth plate 6 is mounted thereon. The

cloth plateG is made of sheet metal and includes 15 a horizontal portion on which the fabric rests and also a depending apron (ia which is united to the horizontal portion of the cloth plate by soldering, brazing, or inV any other suitable way,

so as to form in substance an integral portion 20 of the cloth plate. This apron is supported entirely by the cloth plate and depends therefrom. The horizontal portion of the cloth plate is yprovided with a lug 1 which is rigidly secured to the cloth plate, and a pivot bolt passes through the 25 cloth plate and the lug 1 and is threaded into the supporting bracket 5. This particular way of mounting the cloth plate is Well known in the art, and is, therefore, shown more or less diagrammatically. The cloth plate rests on another sup- 30 porting bracket when in position to cover the parts and support the fabric for stitching. It may, however, be readily moved to uncover the parts and give access thereto. As a consequence, the cloth plate is not rigid with the supporting 35 bed.

In a sewing machine such as shown in the patent above referred to, stitches may be produced at the rate of from four tov five thousand per minute. The needle, the looper and the feed are mounted for reciprocation or oscillation, and each moves through its cycle for each stitch formation. This necessarily tends to create rapid vibrations in the supporting parts for these rapidly moving members. The vibrations are trans- 45 mitted to the cloth plate, and when the cloth plate is made of sheet metal and is mounted so that it may move, excessive vibration has been created in the parts of the cloth plate resulting in an objectionable noise. The present invention 50 has to do with the means for absorbing or dampening the vibrations so as to overcome this objectionable noise incident to the rapidly moving parts in the sewing machine. The under face r of the horizontal portion of the cloth plate 6 has 05 attached thereto a layer of cork indicated at 8. The cork layer is cemented to the under face of the cloth plate. The cement connection extends throughout the entire extent of the cork layer. On the inner face of the depending apron and extending all the Way around and covering substantially the entire surface thereof is a layer of cork 9. This layer of cork is likewise cemented throughout the entire extent thereof to the metal apron. The cork layers are thus firmly attached to the metal parts and Vibrations which are transmitted to the metal parts are absorbed or dampened by the cork layer which must necessarily partake of the vibrations transmitted to the metal parts. When the cloth plate is covered with this layer of cork in the manner described, objectionable noise incident to the vibration of the sheet metal parts of the cloth plate are avoided.

It will be understood that in the place of cork, other non-metallic brous material may be used, but it is found that the corkv is more eilicient for this purpose. It will also be understood that a similar cork lining or sound dampening means may be used in connection with sheet metal covering plates in other parts of the sewing machine.

"Having thus described the invention, what I claim as new and desire to secure by Letters- Patent, is Y 1. A cloth plate for the actuated parts of a sewing machine comprising a sheet metal member, and a thin layer of non-metallic fibrous material cemented to one face of said sheet metal member substantially throughout the entire extent thereof for absorbing and dampening the sound creating Vibrations therein.

2. A cloth plate for sewing machines comprising a sheet metal member for Supporting the fabric during stitching and a. depending sheet metal member rigidly united therewith for covering the actuating parts beneath the cloth plate, an-d a thin layer'of non-metallic fibrous material cemented to the inner faces of said metal parts substantially throughout the entire extent thereof for absorbing and dampening the sound creating vibrations therein.

3. A cloth plate for sewing machines comprising a sheet metal member for supporting the fabric during stitching, a depending sheet metal member rigidly united thereto for covering the actuated parts beneath'the cloth plate, and a thin layer of cork cemented to the inner'faces of the metal parts substantially throughout their entire extent for absorbing and dampening the sound creating vibrations therein.

RICHARD MACKAY, JR.

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