US3066627A

US3066627A - Sewing machines

Info

Publication number: US3066627A
Application number: US6308A
Authority: US
Inventors: Schlosser Erwin; Meier Gunther
Original assignee: Gritzner Kayser AG
Current assignee: Gritzner Kayser AG
Priority date: 1959-02-02
Filing date: 1960-02-02
Publication date: 1962-12-04
Anticipated expiration: 1979-12-04
Also published as: GB926571A; CH376355A; FR1246617A; DE1136562B

Description

Dec. 4, 1962 E. SCHLOSSER ET AL SEWING MACHINES Filed Feb. 2. 1960 2 Sheets-Sheet l D 4, 1952 E. SCHLOSSER ETAL 3,066,627

SEWING MACHINES Filed Feb. 2, 1960 2 Sheets-Sheet 2 INVENTOR-S [KW/A Jab 105:6? By quwr/rae Ari/Ex United States Patent Ofifice 3,%5,6Z7 Patented Dec. 4, 1962 3,066,627 SEWEING MACHINES Erwin Schlesser and Gi'lnther Meier, Karlsruhe-Durlach,

Germany, assignors to Gritzner-Kayser Aktiengesellschaft, Karlsmhe-B'urlach, Germany, a, company of Germany Filed Feb. 2, 195.49, Ser. No. 6,3iiii Claims priority, application Germany Feb. 2., 1959 6 Claims. ill. 112--26@) The present invention relates to sewing machines of the kind wherein a supporting arm for the material to be sewn extends parallel to the arm of the machine. In sewing machines of this kind, the drive for the lower stitch-forming instruments, including the drive for the feed dog, is fitted in the material supporting arm which is constructed as an arm extending freely from the base of the machine.

It is very desirable to provide the material-supporting arm with the smallest possible cross section because such a cross section makes it easier for the operator to slip tubular sewing material over the arm, for example for the purpose of darning. It has hitherto been very difiicult to combine such requirement with the task of constructing the drive for the lower stitch-forming instruments, simply, cheaply and robustly. In this respect driving means which comply with such requirements occupy a comparatively large amount of space and necessarily lead to a considerable increase in the cross section of the material supporting arm.

The object of the present invention is to provide a sewing machine which is fitted with a freely projecting material supporting arm and in which the act of guiding the sewing material, particularly for the purpose of darning of stockings or other tubular material is facilitated and wherein at the same time a cheaply manufactured, reliably operating and eficient drive is accommodated within a minimum cross section of the material supporting arm.

In achieving the said object in accordance with the present invention, the material supporting arm of the sewing machine is disposed rearwardly of the machine arm but at its free end has a cranked or short forearm part which extends forwardly conveniently to a position below the stitch forming mechanism depending from the machine arm.

Such a construction greatly facilitates work of the operator on the supporting arm of the machine in that both hands have convenient lateral access to the stitch-forming position without the operator having to approach the machine from the front in an unaccustomed manner or without constructing the machine with dimensions which exceed those of a normal sewing machine having a material-supporting arm. Furthermore, in the said cranked part of the material-supporting arm, which is very important for the invention, the drive of a rotating looper located transversely to the direction of sewing can be accommodated with the use of a pair of-bevel gears of normal dimensions and with a transmission ratio 1:2.

.A very favourable and space-saving arrangement is achieved according to the present invention by the feature that the transmission of the rising and advancing movement to the feed dog, accommodated in the cranked part, is effected by two levers extending one above the other and bent at right angles out of the supporting arm into the crank bend. This makes it possible to use for the transmission movement even the narrow passage between the pair of bevel gears for driving the looper shaft and the outer wall of the material supporting arm.

Further features of the invention and details of the advantages achieved thereby will be apparent from the following description of one embodiment of a sewing machine illustrated by way of example in the accompanying drawings in which:

FIGURE 1 is a perspective view of the machine.

FIGURE 2 shows the material supporting arm alone on a larger scale and with the stitch plate and cover thereof detached.

FIGURE 3 is an inclined view of the machine from the rear, with the cover of the supporting arm removed.

FIGURE 4 shows the underside of the cover of the supporting arm.

FIGURE 5 is a section through the securing means for the stitch plate.

FIGURE 6 is a section taken on the line VIIIVIII of FIGURE 7.

The illustrated machine (FIGURES 1 and 3) has the usual base plate 1 on which is mounted a base 2 to which is connected in turn a casting which comprises a standard or column 3 formed integrally with an arm 4 and a head 5. The parts fitted in the arm 4 and in the head 5 are constructed in known manner and accordingly in the drawings only those parts which are visible from outside are shown, such as for example the needle bar 6, the presser bar 7 (FIGURE 1) and the lifting lever 8 for the presser (FIGURE 3).

The material-supporting arm indicated as a whole by the reference and having a front wall 9a and a rear wall 91; projects from the base 2. The supporting arm extends parallel to the machine arm 4, but is arranged somewhat to the rear relatively to said arm 4. It also is formed at its free end with a cranked or forearm part 10 (FIGURE 1) which extends forwardly, with the stitchforming position located near the front thereof.

This makes it possible for an operator, when working on sewing material which has been slipped over the supporting arm 9, to have access conveniently with both hands to the side of the stitch-forming position without having to approach the machine from the left. When darning tubular sewing material, this conveniently can be guided backwards and forwards transversely to the feed direction in the peripheral direction of the tubular form.

The fiat top of the supporting arm 9 is formed by a cover 11 having a. projection 12 (FIGURES 2 and 4) which engages a recess 13 (FIGURES 2 and 3) of the base. Near the stitch-forming position the cover 11 is held centred by a screw 14 (FIGURE 2) which extends through an opening 15 in the cover 11 and engages a threaded bore 16 in the supporting arm 9.

A finger 17 (FIGURE 4) for holding the cage of the looper 18 is mounted on the cover 11 and as shown, this facilitates assembly. In addition, the space in the cranked part or forearm part 10 for the rotating looper 18 is accessible even when the cover 11 is in position due to the fact that a flap 20 is hinged to the supporting arm 9 by means of a hinge joint 19, said flap 20 defining the forward wall of the cranked part or forearm 10 and which by means of a lock spring (not shown) provided thereon, engages a recess (not shown) in the base of the supporting arm 9 and in this manner is resiliently secured in the closed position.

The lower stitch-forming devices accommodated in the crank part 11 that is to say, the looper 18 and the feed dog 22, are driven by two shafts journalled in the supporting arm, the rotating drive shaft 23 for the looper and the oscillating feed shaft 24 for the feed dog.

Both

shaft

23 and 24 are journalled at one end in an intermediate or transverse wall 25 of the supporting arm 9 to which is connected another intermediate wall 26. The latter is provided with a bearing bushing 27 for mounting the looper shaft 28 (FIG. 3). The wall 26 is continuous with a third intermediate wall 29 in which an opening is arranged, necessary for reasons of manu- Q facture, which is closed by means of a fiat plug (FIG. 2).

A first bevel gear 31 mounted on the drive shaft 23 for the looper and a second bevel gear 32 of half the number of teeth of that of the first gear 31 and meshing therewith and arranged on the looper shaft 28, are adapted to operate in a space bounded by the

intermediate walls

25, 26 and 29. The cover 11 is constructed so that

suitable conformations

33, 34 and 35 (FIGURE 4) of the cover 11 will come to rest on the

intermediate walls

25, 26 and 29. This results in the formation of an enclosed space in which the

bevel gears

31, 32 are protected against becoming soiled, particularly by sewing dust.

When darning, the feed dog 22 should be rendered inoperative. For this purpose a stitch plate 36 (FIGS. 2, 5 and 6) is provided, the periphery of which is symmetrically constructed with respect to a straight line 37 (FIGURE 2) which intersects the carrier arm 9 at an angle of 45 so that it has two

equal sides

38 and 39, the side 38 of which has an arched cover 40 with stitch hole 41 and the side 39 has slots 42 for the passage of the feed dog 22 and also a stitch hole 43. By raising the stitch plate 36 from the supporting arm 9, turning the stitch plate about the straight line 37 as a pivot and reseating it, the part of the stitch plate 36 with the arched cover 40 or the part with the slots 42 can optionally be located at the stitch-forming position, i.e. below the needle bar 6.

For this purpose the stitch plate 36 should be turned and a rapid fixing means is provided for said plate, which makes it possible to secure the plate reliably in both positions Without the use of a tool such as a screwdriver and without any parts projecting from the upwardly directed side hindering the movement of the sewing material.

A double-sided locking spring 45, which is disposed below an opening 46 in the cover 11 is riveted to the angular member 44 (FIG. 5) threadedly secured to the underside of the cover 11. A bolt 48 is arranged to be loosely displaceable in a bore 47 of the stitch plate 36 and carries rounded heads 49 on each side of the stitch plate 36.

It will be seen from FIGURE 6 that the locking spring secured to the cover 11 retains the lower head 49 drawing it somewhat downwardly so that the upper head 49 is drawn against the top of the stitch plate 36 in a manner which does not prevent the movement of the sewing material. As shown in FIG. 6 the locking spring 45 holds the lower head 49 in slightly downwardly biased Y position, so that the upper head 49 is drawn against the upper surface of the stitch plate 36 in a manner that does not impede the passing of the material being sewn. By this means the stitch plate is retained in its position. In this position, the stitch plate is also centered by pins 50 (FIGURE 2) on the cover 11 and by holes 51 in the stitch plate 36.

For turning the stitch plate 36 the operator needs merely to reach under the stitch plate 36 from a troughshaped depression 52 (FIGURES 2 and 5) in the cover 11, to raise said stitch plate against the force of the lock spring 45 in order to turn its axis of symmetry 37 and to dispose it again on the cover, taking into account the centring means 50, 51. After this it is only necessary to press in the bolt 48 and to allow its lower head 49 to engage in the lock spring 45.

In the foregoing, the invention has been described with reference to a specific illustrative device. It will be evident, however, that variations and modifications, as well as the substitution of equivalent elements for those illustrated, may be made without departing from the scope and broader spirit of the invention as set forth in the appended claims. The specification and drawings are accordingly to be regarded in an illustrative rather than in a limiting sense.

We claim:

1. In a sewing machine having a vertical standard mounted on a base and supporting a horizontally disposed machine arm having a machine head, a needle bar supported in said head and extending vertically downwardly therefrom, a material supporting arm extending from said base generally parallel to and relatively rearwardly of said machine arm, and having a front wall and a rear wall, and a forearm part extending at right angles to and from said suppodting arm below said machine head, said forearm part having a forward wall disposed generally within the vertical confines of said head, an intermediate wall substantially in alignment with said front wall and parallel to said forward wall, a looper supported by said intermediate wall and a feed dog disposed on said forearm part proximate said forward wall thereof and below said needle bar.

2. In a sewing machine having a vertical standard mounted on a base and supporting a horizontally disposed machine arm having a machine head, a needle bar supported in said head and extending vertically downwardly therefrom, a material supporting arm extending from said base generally parallel to and relatively rearwardly of said machine arm, and having a front wall and a rear wall, and a forearm part extending at right angles to and from said supporting arm below said machine head, said forearm part having a forward wall disposed generally within the vertical confines of said head, an intermediate wall substantially in alignment with said front wall and parallel to said forward wall, a looper supported by said intermediate wall and a feed dog disposed on said forearm part proximate said forward wall thereof and below said needle bar, said rear wall of said material supporting arm being flush with and a continuation of said base and said forward wall being a portion of a flap hingedly connected to said forearm part.

3. In a sewing machine having a vertical standard mounted on a base and supporting a horizontally disposed machine arm having a machine head, a needle bar supported in said head and extending vertically downwardly therefrom, a material supporting arm extending from said base generally parallel to and relatively rearwardly of said machine arm, and having a front wall and a rear wall, and a forearm part extending at right angles to and from said supporting arm below said machine head, said forearm part having a forward wall disposed generally within the vertical confines of said head, and a feed dog disposed on said forearm part proximate said forward wall thereof and below said needle bar, said rear wall of said material supporting arm being flush with and a continuation of said base, said material supporting arm enclosing a looper drive shaft supporting a first bevel gear adjacent said forearm part and said forearm part enclosing a looper adjacent said forward wall thereof and below said feed dog and a looper supporting shaft disposed at right angles to said looper drive shaft and having a second bevel gear in meshing relationship with said first gear, said second gear having one half the number of teeth than said first gear, and said forward wall being a portion of a hinged flap movable to permit access to said looper.

4. In a sewing machine having a vertical standard mounted on a base and supporting a horizontally disposed machine arm having a machine head, a needle bar supported in said head and extending vertically downwardly therefrom, a material supporting arm extending from said base generally parallel to and relatively rearwardly of said machine arm, and having a front wall and a rear wall, and a forearm part extending at right angles to and from said supporting arm below said machine head, said forearm part having a forward wall disposed generally within the vertical confines of said head, and a feed dog disposed on said forearm part proximate said forward wall thereof and below said needle bar, said rear Wall of said material supporting arm being flush with and a continuation of said base, said material supporting arm enclosing a looper drive shaft supporting a first bevel gear adjacent said forearm part and said forearm part enclosing a looper adjacent said forward wall thereof and below said feed dog and a looper supporting shaft disposed at right angles to said looper drive shaft and having a second bevel gear in meshing relationship with said first gear, said second gear having one half the number of teeth than said first gear, and said forward wall being a portion of a hinged flap movable to permit access to said looper, said material supporting arm having a transverse wall including journal means for said looper drive shaft and a wall extending into said forearm part at right angles to said transverse wall including journal means for said looper supporting shaft, and said Walls including said journal means defining a housing for said bevel gears.

5. In a sewing machine having a vertical standard mounted on a base and supporting a horizontally disposed machine arm having a machine head, a needle bar supported in said head and extending vertically downwardly therefrom, a material supporting arm extending from said base generally parallel to and relatively rearwardly of said machine arm, and having a front wall and a rear wall, and a forearm part extending at right angles to and from said supporting arm below said machine head, said forearm part having a forward wall disposed generally within the vertical confines of said head, an intermediate wall substantially in alignment with said front wall and parallel to said forward wall, a looper supported by said intermediate wall and a feed dog disposed on said forearm part proximate said forward wall thereof and below said needle bar, a stitch plate adapted to be selectively reversed into a position for covering said feed dog and into a position to accommodate said feed dog, said plate having a portion presenting an arcuate formation having a needle aperture and a portion presenting slots for the passage of said feed dog, said portions being arranged symmetrically relative to an axis of symmetry intersecting said portions and disposed at an angle of relative to each of said portions.

6. A sewing machine in accordance with claim 5 comprising said stitch plate, a bore provided. along said axis of symmetry, a bolt having heads at opposite ends received in said bore, a latching spring arranged within said supporting arm adapted to receive and interlock with one of said heads, thereby drawing said stitch plate downwardly against said supporting arm and said forearm part.

References Cited in the file of this patent UNITED STATES PATENTS 1,424,854 Rogers Aug. 8, 1922 1,452,696 Mock Apr. 24, 1923 2,569,091 Robert Sept. 25, 1951 2,656,805 Reinhold Oct. 27, 1953 2,918,027 Johnson Dec. 22, 1959 2,944,497 Waterman July 12, 1960 2,945,461 Perla July 19, 1960 FOREIGN PATENTS 896,246 France Apr. 24, 1944