JPH0539482U - Vertical full rotary hook - Google Patents

Abstract

(57) [Abstract] [Purpose] The bobbin case has a bobbin case with a bobbin case to prevent the upper thread from getting caught in the inner hook or bobbin case and to prevent the lower thread from looping in the bobbin case. Provide a vertical full rotation hook locked to. [Structure] A distal end portion of a rail portion 14 of a tubular portion 13 is partially cut out from a detent recess 15 along an outer hook rotational direction A, and a flange 16 is provided radially outward from the remaining distal end of the tubular portion.
Has an inner rotary hook 11 projecting therefrom and a bobbin case 21 in which a peripheral wall 22 and first and second projections are formed so as to be continuous with the remaining cylindrical portion 13, and an end of the bobbin case 21 is provided. The idling prevention spring arranged on the inner surface of the plate 24 is provided with a protruding piece projecting on the outer periphery of the spring locking groove provided on the peripheral wall 22 of the bobbin case 21 and the first protruding portion and the second protruding portion. The structure is adapted to be inserted and engaged with a spring locking slit to be fixed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a vertical full rotary hook of a sewing machine.

[0002]

[Prior Art]

 In recent years, many bobbin diameters have been increased in order to increase the winding amount of the bobbin in the vertical full rotary hook of the sewing machine.To increase the bobbin diameter, a part of the inner hook cylindrical part is circumferentially extended. A bobbin case having a notch and a peripheral wall corresponding to the notch and connected to the remaining inner hook tubular portion is assembled. In this bobbin case, as shown in FIG. 16, the end plate 5 of the bobbin case 3 projects outward in the radial direction on the upstream side of the rotation stopper recess 4 in the rotation direction of the outer hook 1 (indicated by arrow A). The downstream end portion thereof serves as a detent protrusion 7, and the detent protrusion 7 is disposed so as to abut the flange 6 of the inner hook 2 in the circumferential direction.

A bobbin case 3 has a plate-shaped anti-slip spring fixed to the bobbin case 3 in order to prevent the bobbin 10 contained therein from idling and causing looping of the bobbin thread and causing thread breakage. There is.

[0004]

[Problems to be solved by the device]

 In such a conventional vertical full rotation, since the upper thread loop pulled up by the balance slides along the outer circumference of the inner hook 2, the flange 6 and the rotation preventing projection 7 are present. The upper thread loop is sandwiched in the gap between 6 and the anti-rotation protrusion 7, the upper thread is not sufficiently pulled up, and the phenomenon that the upper thread sags easily occurs.

Further, in the case where the bobbin case 3 has only a part of the peripheral wall in order to increase the winding amount of the bobbin thread, it is difficult to lock the idling prevention spring to the bobbin case 3, and the idling prevention spring is dropped when the bobbin is replaced. The bobbin 10 spins idly due to an unstable locking state during sewing, and the bobbin thread becomes a ball or looping occurs, and the bobbin thread is easily cut.

An object of the present invention is to solve these problems and to provide a vertical full-rotation rotary hook that prevents sagging phenomenon or cutting of the upper thread and the lower thread and obtains high sewing performance.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, according to the present invention, the tip portion of the tubular portion opposite to the bottom portion is cut out from the detent recess along the rotation direction of the outer hook from about 65 ° to about 205 °. The outer hook of the detent recess has an inner hook with a flange projecting radially outward from the remaining tip of the cylinder on the upstream side in the rotational direction of the rotary hook. The peripheral wall is formed so as to be continuous in the direction, and the spring locking groove is provided at one position of the base end, and is formed on the downstream side in the outer hook rotational direction with respect to the peripheral wall, and is formed so as to sandwich the recess for attaching the latch member. A bobbin case having first and second protrusions provided with spring locking slits at opposing positions of the base end portion, and a substantially half-moon shaped end plate integrally formed with the peripheral wall and the protrusion, and an end of the bobbin case. It is placed on the inner surface of the plate and contacts the flange surface of the bobbin. A vertical spring characterized by including a slip prevention spring having a projecting piece that engages with the spring locking slit and the spring locking groove projectingly provided on the outer periphery thereof. There are all rolls.

[0008]

[Action]

 When the sewing machine is driven and sewing is started, the needle thread is guided to the tip of the sword of the outer hook to form a loop, and this loop is gradually expanded as it moves to the vicinity of the lower end of the inner hook, and the lower end of the inner hook is expanded. pass. Since the upper thread loop passing through the lowermost end of the inner hook is slackened around the inner hook, the upper thread of the cloth starts to move from the peripheral wall of the bobbin case to the inner hook from the peripheral wall of the bobbin case. After that, the needle thread loop slides on the flange as it rises, and the needle thread loop is smoothly pulled up without being caught by the flange tip. Therefore, no thread ball or looping will occur on the upper thread.

Since the idling prevention spring is securely fixed in the bobbin case by the protrusion, it does not fall off from the bobbin case when replacing the bobbin, and the bobbin does not slip when sewing, and the bobbin thread is looped, etc. It is also possible to prevent thread breakage due to the cause of.

[0010]

【Example】

 FIG. 1 is an overall perspective view of a vertical full rotation rotary hook showing an embodiment of the present invention. The vertical full rotary hook of the present invention includes an outer hook 1 that rotates in the direction of arrow A, an inner hook 11 that is housed in the outer hook 1, and a bobbin case 21 that is housed in the inner hook 11 and that houses the bobbin 10. The bobbin case 21 is provided with a bobbin slip prevention spring.

FIG. 2 is a front view of the inner hook, FIG. 3 is a left side view of the inner hook, FIG. 4 is a plan view of the inner hook, and FIG. 5 is a rear view of the inner hook. FIG. 6 is a cross-sectional view taken along the section line VI-VI of FIG. 5. As shown in these drawings, the inner hook 11 has a bottom portion 12 and a tubular portion 13 formed at a right angle to the bottom portion 12 and having a rail 14 projecting from the outer surface thereof. A detent recess 15 is provided at one location on the opposite end. Further, in the tubular portion 13, the tip end portion from the rail 14 is notched from the rotation stopper recess 15 to the downstream side along the outer hook rotation direction A over a range from a circumferential angle α to β, and the rotation stopper recess 15 is formed. A flange 16 is provided so as to project radially outward of the inner rotary hook 11 from the tip of the remaining cylindrical portion on the upstream side in the outer rotary hook rotational direction A. The flange 16 is formed so that the radius of the outer peripheral surface of the flange 16 smoothly increases along the outer hook rotating direction A and sharply decreases after passing through the detent recess 15. According to the embodiment, the value of α is set to about 65 ° and the value of β is set to 205 °.

As shown in FIGS. 2 and 3, a protrusion of the bobbin case 21 is provided on the tubular portion 13 of the inner rotary hook 11 and the flange 16 at a position of about 90 ° on the upstream side of the rotary hook recess 15 in the rotary hook rotational direction. An opening 30 is formed in which the section and the tail end of the latch member (both described later) are inserted.

FIG. 7 is a front view of the bobbin case 21 of the present invention, FIG. 8 is a right side view of the bobbin case, and FIG. 9 is a rear view of the bobbin case.

As shown in these figures, when the bobbin case 21 is mounted on the inner hook 11, a peripheral wall formed so as to be continuous in the circumferential direction with respect to the tip end portion of the inner hook 11 where the inner hook 11 remains. 22, a first protrusion 23a and a second protrusion 23b that are formed on the downstream side of the peripheral wall 22 in the rotary hook rotational direction downstream, and the peripheral wall 22 and the first and second protrusions 23a and 23b that are integral with each other. Formed end plate 24. As shown in the front side perspective view of FIG. 10 and the rear side partial perspective view of FIG. 11, the first and second protrusions 23a, 23b are provided with recesses 25 for assembling the latch member 40 mounted on the bobbin case 21. It is formed on both sides across. Further, the end plate 24 is notched as a plane connecting the starting end 22a of the peripheral wall 22 and the terminal end 23c of the second protrusion 23b along the outer hook rotating direction as an end face 26, and has a substantially half-moon shape. As shown in FIG. 10, the end face 26 of the end plate 24 is provided with an end face guide groove 26a that tends from the outer peripheral back surface of the end plate toward the inner peripheral surface thereof. This end face guide groove 26a is provided when the bobbin 10 with the bobbin thread is attached to the bobbin case 21 so as to prevent the free end of the bobbin thread from being caught by the sword tip of the outer hook 1 at the beginning of sewing with a sewing machine. , A groove for introducing its free end in advance.

As shown in FIG. 11, the bobbin case 21 is provided with spring engaging slits 28a and 28b at the base end portions of the first protruding portion 23a and the second protruding portion 23b, respectively, on opposite sides. Further, as shown in the partial perspective view on the rear side of FIG. 12, a spring locking groove 29 is provided at the base end portion of the peripheral wall 22 which is deviated from the spring locking slits 28a, 28b by approximately 180 ° in the circumferential direction. There is. The spring locking slits 28a, 28b and the spring locking groove 29 are used to fix the idling prevention spring 31 to the bobbin case 21.

As shown in the plan view of FIG. 13 and the front view of FIG. 14, the idling prevention spring 31 has an outer peripheral shape substantially the same as that of the end plate 24 of the bobbin case 21. The braking part 32 formed so as to surround, the outer ring part 33 bent along the peripheral wall 22 of the bobbin case 21, the bending part 32 along the outer ring part 33, and the braking part 32 and the outer ring part 33 are connected. When the idling prevention spring 31 is mounted on the inner surface of the bobbin case 21, the spring retaining slits 28a, 28b and the spring retaining groove of the peripheral wall 22 are provided on the outer periphery of the outer ring portion 33. A protruding piece 35 is formed which is inserted into and engages with 29. In the idling prevention spring 31, as shown in FIG. 14, the braking portion 32 is raised through the inner ring portion 34. As a result, when the bobbin 10 is mounted on the bobbin case 21, the braking portion 32 comes into contact with the flange surface to prevent the bobbin 10 from idling, prevent the slack of the lower thread, and prevent the lower thread from looping. Prevent it from happening.

As shown in the overall perspective view of FIG. 1, the full rotary hook of the present invention has an inner hook 11 assembled to the outer hook 1 and fixed to a lower rotary drive shaft 8 and then fitted with a hook stopper member 9. Although assembled, the bobbin 10 in which the bobbin thread is wound in a rod tube state is attached to the bobbin case 21 prior to sewing. The lower thread of the bobbin 10 is passed through a lower thread guide groove 22b (see FIG. 12) provided on the peripheral wall 22 and pressed by the thread tension spring 42, and the thread end is further guided to the end face guide groove 26a (see FIG. 10). Refer to the above).

An idling prevention spring 31 is fixed to the bobbin case 21.

From these things, even when sewing is started, the sword tip of the outer hook 1 reliably captures the lower thread, but troubles such as the free end of the lower thread wrapping around to the bottom side of the inner hook 11 are prevented. Be removed.

Since the idling prevention spring 31 is locked to the bobbin case 21 by the projecting piece 35 provided on the outer periphery thereof, it is securely fixed, the spring force is stabilized, and the bobbin 10 is prevented from idling. This prevents looping of threads and improves sewing performance of the sewing machine.

Further, according to the vertical full rotary hook of the present invention, the flange 16 of the inner hook 11 is formed in the vicinity of 205 ° along the outer hook rotational direction from the detent recess 15. As shown in the upper thread moving state explanatory diagram of FIG. 15, this vicinity corresponds to a position where the tension of the upper thread loop T temporarily starts to be attenuated, and the upstream start end 16a of the flange 16 has the bobbin case 21. Since the upper thread loop T stretched between the end plate surface 24a of the upper hook and the sword tip (not shown) of the outer hook is formed near the bottom of the inner hook 11 to the extent that it does not come into contact with the upper hook loop T, the upper thread loop T When is transferred from the surface of the bobbin case to the surface of the flange, the tension balance is not lost by being caught by the starting end 16a of the flange 16. As described above, according to the present invention, the upper thread can be moved while smoothly sliding on the flange 16 without the conventional upper thread being caught.

[0022]

[Effect of the device]

 As described above, according to the present invention, a flange outwardly in the radial direction of the inner hook is provided on the downstream side from the position of 205 ° along the rotation direction of the outer hook from the detent recess. Therefore, the needle thread loop moves while sliding on the outer edge of the flange without coming into contact with the upstream start end of the flange. Therefore, unlike the conventional case, the upper thread is not caught by the flange or the like and the tension balance is not lost.

Further, the idling prevention spring has a plurality of protrusions protruding from the outer periphery thereof, and the protrusions are inserted into the bobbin case and locked, and the braking portion abuts the flange surface of the bobbin for braking. , It is firmly fixed, the spring force is stable, slack of the lower thread does not occur, and the sewing performance of the sewing machine is improved.

[Brief description of drawings]

FIG. 1 is an overall perspective view of a vertical full rotation rotary hook showing an embodiment of the present invention.

FIG. 2 is a front view of an inner hook.

FIG. 3 is a left side view of the inner hook.

FIG. 4 is a plan view of an inner hook.

FIG. 5 is a rear view of the inner hook.

6 is a cross-sectional view taken along the section line VI-VI in FIG.

FIG. 7 is a front view of the bobbin case.

FIG. 8 is a right side view of the bobbin case.

FIG. 9 is a rear view of the bobbin case.

FIG. 10 is a perspective view of the bobbin case viewed from the front side.

FIG. 11 is a partial perspective view of the bobbin case viewed from the back side.

FIG. 12 is another partial perspective view seen from the back side of the bobbin case.

FIG. 13 is a plan view of a slip prevention spring.

FIG. 14 is a front view of a slip prevention spring.

FIG. 15 is a front view illustrating a moving state of the upper thread loop.

FIG. 16 is a front view of a conventional vertical full rotation rotary hook.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 outer hook 10 bobbin 11 inner hook 13 tubular part 15 rotation stop recess 16 flange 21 bobbin case 22 peripheral wall 23a first projection 23b second projection 24 end plate 28a, 28b spring locking slit 29 spring locking groove 31 idle rotation Prevention spring 32 Braking part 35 Projection piece 40 Latch member

Claims (1)

[Scope of utility model registration request] 1. The cylindrical portion on the side opposite to the bottom portion, the tip portion of which is more than 65 ° along the rotation direction of the rotary hook from the rotation-stop recess, rather than the rail.
From about 205 ° to about 205 °, the inner hook with the flange protruding radially outward from the remaining tip of the cylindrical portion on the upstream side of the rotary hook in the rotation preventing recess in the rotational direction, and the inner hook remaining. A peripheral wall that is formed so as to be continuous in the circumferential direction with respect to the distal end of the tubular portion, and has a spring locking groove at one location on the base end, and is spaced apart on the downstream side in the rotary hook rotation direction with respect to the peripheral wall, and has a latch member assembled A bobbin having first and second protrusions which are formed sandwiching a recess and in which spring locking slits are provided at opposing positions of a base end portion, and a substantially half-moon shaped end plate integrally formed with the peripheral wall and the protrusion. A plate-shaped spring having a case and a braking portion arranged on the inner surface of the end plate of the bobbin case and in contact with the flange surface of the bobbin, the outer periphery of which is engaged with the spring locking slit and the spring locking groove. If the idling prevention that the protruding piece is installed A vertical full-turn hook characterized by including a foot.