US2598452A

US2598452A - Lighting device for sewing machines

Info

Publication number: US2598452A
Application number: US786698A
Authority: US
Inventors: Singer Mor Josif; Draaisma Gijsbertus Hendricus
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-11-28
Filing date: 1947-11-18
Publication date: 1952-05-27
Anticipated expiration: 1969-05-27
Also published as: FR956033A; BE477712A; CH260274A; GB637833A; NL62233C

Description

May 27, 1952 M. J. SINGER ETAL LIGHTING DEVICE FOR SEWING MACHINES Filed NOV. 18, 1947 Patented May 27, 1952 LIGHTING DEVICE FOR SEWING MACHINES Mor Josif Singer, Tilburg, and Gijsbertus Hendricus Draaisma, Amsterdam, Netherlands Application November 18, 1947, Serial No. 786,698 In the Netherlands November 28, 1946 2 Claims. I

The present invention relates to a lighting device for sewing machines, and more particularly to a reflector attached to the bottom face of the head of a sewing machine.

It is the object of the present invention to provide a reflector for sewing machines permitting lighting of the Working area without producing a shadow of the pressure foot and the needle holder.

It is another object of the present invention to provide a reflector which prevents light from reaching the eyes of the operator of the sewing machine.

It is a further object of the present invention to provide a reflector which is of small size and does not obstruct the movements of the operator of the sewing machine.

It is a still further object of the present invention to provide a lighting device which sufliciently lights the working area of the sewing machine while consuming a minimum of electric power.

It is still another object of the present invention to attach a lighting device to a sewing machine in such manner that the device does not vibrate when the machine is operated.

It is also an object of the present invention to provide a reflector for a sewing machine which may be inexpensively manufactured and easily attached to the head of a sewing machine.

With these objects in view the present invention mainly consists in a single reflector having a horizontal top wall provided with a non-reflecting top face and a reflecting bottom face. The reflector is mounted on a sewing machine with the upper face of the top wall thereof abutting against the bottom face of the machine head. A hole is provided in the top wall permitting passing of the presser foot bar.

The reflector has on either side oppositely arranged downwardly bent edge wall portions. Light emitted by bulbs arranged below the reflector parallel and adjacent to the bent edge wall portions is reflected downwardly towards the working area of the sewing machine.

A cut-out is preferably provided in the front edge of the top wall and permits viewing of the presser foot bar and needle of the sewing machine during a sewing operation.

The reflector may be attached to the machine head by a hooked tongue which is secured to the reflector, and clamped to the machine head by means of a nut or screw, which is provided on most sewing machines for lubrication. However, the reflector according to the present invention may be attached to the head of the sewing machine by any other attachment means.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with addi-- tional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Fig. 1 is a diagram showing variation ofthe light intensity over the working area of a sewing machine;

Fig. 2 is a perspective view of a sewing machine head with a reflector according to the present invention attached thereto;

Fig. '3 is a bottom view of a lighting device according to the present invention;

Fig. 4 is a cross-section on line 4-4 of Fig. 3;

Fig. 5 is a rear view of a sewing machine provided with a reflector according to the present invention; and

Fig. 6 is a perspective view of means for supplying electric current to the lighting device according to the'present invention.

Referring now to the drawings, Figure 2 illustrates the head 0 of a sewing machine provided with presser foo-t C and a screw b which is provided on most sewing machines to cover a 'lubrieating channel. A reflector a is attached to the bottom face of the machine head by meansof a hook shaped, or perforated tongue d.

The construction of the lighting device according to the present invention can be better seen from Figures 3 and 4. The reflector a comprises a top wall I which is provided with a hole 2 through which the presser foot C of the machine passes When the device is attached to the sewing machine. Two lateral curved wall portions 3 are downwardly bent to reflect the light inwardly. A cut-out 4 is provided on the front edge of the reflector, and permits viewing of the presser foot during operation of the machine. Elongated bulbs 5 are mounted below the top wall adjacent and parallel to the bent wall portions 3 in depressed portions 6. Instead of the depressed portions, holes may be provided for receiving the pointed ends of the bulb sockets. On the rear wall I of the reflector a spring 8 is mounted which is also provided with depressed portions, or holes 9. The contact spring 8 is connected to an insulated wire [0, while the reflector and the terminal of the bulb 5, mounted in the depressed portion 6, is connected to the mass of the machine.

As shown in Figures 5 and 6, the insulated wire l0 leads to a contact H on the underside of the supporting plate of the sewing machine, so that when the machine is in operating position the contacts H engage the contacts I2 which are connected to a transformer l3. This arrangement permits removing of the machine from the table without removing the lighting device from the machine head.

A variable resistor may be arranged within the a transformer housing permitting adjustment of the current supply to the bulbs and thereby of the intensity of the light to be produced in the Working area. Also, the transformer may be tapped to provide different voltages. These arrangements permit adaptation of the light produced by the lighting device to the lighting of the room in which the operation is carried out, and to the color of the material.

The above-described reflector produces an almost shadowless light in the working area, and due to its low position, the operator can never see the brightly lighted inner face of the reflector. The upper surface of the reflector is non-reflecting and preferably black.

Referring now to Fig. 1, the reference numeral 12' indicates a graph showing the variations of light intensity of known lighting devices for sewing machines, the needle of the machine being assumed to be located at the zero point of the scale. Reference numeral (1. indicates the light intensity variations produced by a device according to the present invention, and it will be noted that, while there is a sharp contrast between the lighted Working area and the surrounding area when a device according to the present invention is used, there is not much difference when the known lighting devices are employed, which leads to fatigue and eye strain of the operator.

Due to the fact that the lighting device is mounted on the machine spaced only a short distance from the machine table, only small lamps are required for producing the desired light intensity, and two electric bulbs of siX watts each are producing optimal results. The close contact of the lighting device with the machine head keeps the temperature of the reflector low since all heat is conducted away by the greater mass of the sewing machine head. Also, the fixed attachment of the lighting device according to the present invention prevents oscillations of the reflector, permitting long use of the bulbs and eliminating stroboscopic effects which frequently occur in other lighting devices for sewing machines due to vibrations.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of lighting device for a sewing machine differing from the types described above.

While the invention has been illustrated and described as embodied in a reflector having a horizontal flat top wall abutting against the bottom face of a sewing machine head, and having lateral downwardly bent edge walls achieving a shadowless illumination of the working area of the sewing machine, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a sewing machine including an elongated vertically extending machine head terminating in a free end having a substantially horizontal bottom face and a vertical presser foot bar projecting from said free end of said machine head through said bottom face, in combination, a single substantially horizontal reflector having a horizontal fiat top wall provided with a non-refleeting top face and a reflecting bottom face and abutting with said non-reflecting top face against said bottom face of said free end of said machine head, said top wall having opposite lateral edges with downwardly bent curved edge wall portions, and being formed with a hole for the passage of said presser foot bar located spaced at equal distances from said downwardly bent curved edge wall portions, said top wall being formed with a cut-out on the front edge thereof adapted to permit viewing of said presser foot bar by an operator; socket means on said refiector oppositely arranged on the front and rear edges of said top wall for mounting elongated bulbs below said reflecting bottom face of said top wall parallel to said downwardly bent'curved edge portions of said top wall; and a vertically extending bracket fixedly secured to said reflector and projecting upward from said'nonreflecting top face of said top wall and formed with a hole so as to be adapted to be secured to the lateral face of said free end of said machine head.

2. In a sewing machine including an elongated vertically extending machine head terminating in a free end having a substantially horizontal bottom face, and a vertical presser foot bar projecting from said free end of said machine. head through said bottom face, in combination, a single substantially horizontal reflector secured to said free end of the machine head and having a flat horizontal top wall provided with a non-reflecting top face and a reflecting bottom face and abutting with said non-reflecting top face against said bottom face of said free end of said machine head, said top wall having opposite lateral edges with downwardly bent curved edge wall portions and being formed with a hole for the passage of said presser foot bar located spaced at equal distances from said downwardly bent curved edge wall portions; and socket means on said reflector for mounting elongated bulbs below said reflecting bottom face of said top wall along said downwardly bent curved edge portions of said top wall.

MOB. JOSIF SINGER. GIJSBERTUS HENDRICUS DRAAISMA.

REFERENCE S CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS France Aug. 1, 1932