JPH0440040B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for automatically attaching and detaching a bobbin and a bobbin case attached to an inner hook of a sewing machine.

Conventionally, when the bobbin thread in the bobbin in the inner hook is consumed during sewing, the bobbin is grasped together with the bobbin case and taken out from the inner hook, and the bobbin, on which the bobbin thread has been wound in advance, is removed from the bobbin case together with the bobbin case. BACKGROUND ART Devices for attaching and detaching a bobbin and a bobbin case that are attached to an inner hook are known.

In such prior art, the bobbin and bobbin case may not be held securely due to slight deviations in the gripping positions, and in such cases, it is necessary to attach the bobbin and bobbin case to the inner hook. Otherwise, the bobbin and bobbin case may come into contact with the inner hook during installation, making it impossible to insert the bobbin and bobbin into the inner hook. There is a problem in that the case cannot be attached or detached.

Problems to be Solved by the Invention An object of the present invention is to provide a sewing machine bobbin and bobbin case mounting device that allows the bobbin and bobbin case to be reliably mounted to and removed from the inner hook.

Means for Solving the Problems The present invention provides a bobbin having a pair of flanges and a right cylindrical winding tube that connects these flanges, and a bobbin that protrudes toward the open end side and is larger than the winding tube of the bobbin. An inner hook having a short shaft portion, a notch extending in the axial direction of the inner hook and opening in the bottom side of the inner hook when installed inside the inner hook, and a notch on both sides of this notch. A bobbin case is formed with a locking groove and has an insertion hole formed coaxially with the axis of the inner hook; A retaining member for locking the bobbin, and a gripping means for attaching and detaching the bobbin housed in the bobbin case by driving the bobbin closer to and away from the inner hook together with the bobbin case, and the gripping means moves along the axial direction. a fitting cylinder having a notch extending therein, which fits into the winding cylinder, whose outer diameter is expanded/reduced in the radial direction, and whose inner peripheral surface has an inclined surface whose diameter expands in a direction away from the inner hook; It is characterized by comprising: a drive member that abuts the inclined surface and drives forward/backward displacement in the axial direction of the inner hook; and a fluid pressure cylinder that drives the drive member forward/backward in the axial direction of the inner hook. This is a device for attaching and detaching the bobbin and bobbin case of a sewing machine.

Effects According to the present invention, the fitting cylinder is inserted into the winding cylinder of the bobbin and is expanded, whereby the bobbin is gripped by the fitting cylinder. In this state, when the gripping means is displaced and driven in a direction away from the inner hook, the bobbin is taken out from the inner hook together with the bobbin case. In addition, the bobbin is stored in the bobbin case,
When the gripping means is driven in a direction approaching the inner hook while being gripped by the fitting cylinder, the bobbin is attached to the inner hook together with the bobbin case. When the bobbin is attached to the inner hook, the retaining member is engaged with the locking groove, and the bobbin and the bobbin case are held within the inner hook.

Embodiment FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is a perspective view of the gripping means 7. The attachment/detachment device 1 of the present invention includes a bobbin 74 having a pair of flanges 73, 75, a right cylindrical winding tube 76 connecting these flanges 73, 75, and a bobbin 74 that protrudes toward the open end side and has a winding tube 76 connected to the flanges 73, 75. The inner hook 3 has a shaft portion 79 formed shorter than the winding tube 76 of the inner hook 3, and the inner hook 3 has a shaft portion 79 that extends in the axial direction of the inner hook 3 and is open to the bottom side of the inner hook 3 when installed inside the inner hook 3. Notch 81
(see FIGS. 5 to 7), a locking groove 93 is formed on both sides of the notch 81, and an insertion hole 118 is formed coaxially with the axis of the inner hook 3. A retaining member 90 (see FIGS. 3 and 4) that is fixed to the inner circumferential surface of the rotary hook 3 and that fits into the notch 81 and elastically engages the locking groove 93, and bobbin 7 stored in
4 is attached to and detached from the inner hook 3 by moving the inner hook 3 toward and away from the bobbin case 6.

The gripping means 7 is formed with a notch 133 extending along the axial direction, fits into the winding tube 76, has an outer diameter expanded/reduced in the radial direction, and has a notch 133 formed on the inner circumferential surface in a direction away from the inner hook 3. a fitting cylinder 124 having an inclined surface 131 with a diameter enlarged to a diameter of 120 mm, a rod 121 that is a driving member that abuts the inclined surface 131 and drives the inner hook to move forward/backward in the axial direction, and the rod 12
1 in the axial direction of the inner hook.

The single acting cylinder 120 includes the rod 121 and
A casing 122 surrounding the rod 121 is included. The casing 122 includes a right cylindrical outer cylinder 123 that surrounds the rod 121, and this outer cylinder 1.
23 (left end in FIG. 1), and is fixed to the mounting member 11 that is driven to move toward and away from the inner hook 3. The fitting tube 124 has a large diameter portion 124a and a small diameter portion 124b. The rod 121 has a piston 125 driven by compressed air from a pneumatic source (not shown).
The piston 125 is configured to be slidable within the inner wall 126 of the outer cylindrical body 123. A seal member 127 is attached to the piston 125, and the seal member 127 closes the outer cylinder 1.
No. 23 room 120a and another room 120b are hermetically sealed off. A coil spring 128 is interposed between one side 129 of the chamber 120a and the piston 125. This coil spring 128 biases the piston 125 and the rod 121 in a direction away from the inner pot 3.

The chamber 120a is the large diameter portion 124 of the fitting tube 124.
The right cylindrical surface 130 is connected to a right cylindrical surface 130 formed inside a, and the right cylindrical surface 130 is connected to a conical surface 131 that is a tapered inclined surface toward the inner pot 3. The conical surface 131 is connected to a right cylindrical surface 132 formed on the small diameter portion 124b.

The tip of the rod 121 (the left end in FIG. 1) is formed into a truncated cone shape corresponding to the conical surface 131. A positioning pin 134 is formed in the large diameter portion 124a of the fitting cylinder 124.

The inner hook 3 is housed in the outer hook 67. The outer hook 67 includes an outer hook body 68 and an inner hook presser 69.
including. A track 71 of the inner hook 3 is rotatably fitted into a track groove 70 defined by the outer hook body 68 and the inner hook holder 69. An iron bobbin case 6 is stored in the inner hook 3, a bobbin 74 is stored in the bobbin case 6, and a bobbin thread 77 is stored in the winding tube 76.
is wound.

3 is a sectional view of the inner hook 3, FIG. 4 is a front view of the retaining member 90 seen from the arrow A1 side in FIG. 3, and FIG. 5 is a front view of the bobbin case 6. , FIG. 6 is a side view seen from the arrow A2 side in FIG. 5, and FIG. 7 is a sectional view taken from the cutting plane line - in FIG. 5. At the bottom 86 of the inner pot 3,
A shaft portion 79 that protrudes toward the mounting member 11 is attached. The shaft portion 79 has an axis that is common to the axis of the lower shaft 72 of the sewing machine. The bobbin case 6 is formed with an insertion hole 118 into which the fitting cylinder 124 of the gripping means 7 can be inserted, and a positioning hole 119 into which the positioning pin 134 is fitted.

A roughly U-shaped retaining member 90 is fixed to the inner circumferential surface of the inner hook 3 with a screw 91. A pair of protrusions 92 of the retaining member 90 are attached to the bobbin case 6.
It fits into the locking groove 93 formed in the notch 81, and is elastically fitted and locked into the locking groove 93 by the legs 90a, 90b of the retaining member 90, and is locked therein. Thus, the bobbin case 6 is held in the inner hook 3.

FIG. 8 is a plan view showing an inner hook 3a according to another embodiment of the present invention, FIG. 9 is a sectional view of a part thereof, and FIG. 10 is a plan view of a bobbin case 6a housed in the inner hook 3a. It is a front view, and FIG. 11 is a side view thereof. A leaf spring 94 is fixed to the outer peripheral wall of the inner hook 3a. The leaf spring 94 is plate-shaped as shown in FIG. 12, and is provided with an engaging projection 95 that projects inward of the inner hook 3a. Further, attachment holes 96 and 97 are formed in this leaf spring 94. An engagement hole 98 corresponding to the engagement protrusion 95 is formed in the inner hook 3a, and a leaf spring 94 is inserted into the inner hook 3a.
The screws 99 and 100 are in contact with the outer peripheral surface of a.
are inserted through the mounting holes 96, 97 and screwed together, and the leaf spring 94 is thus fixed to the inner hook 3a.

The engaging protrusion 9 is provided on the side wall of the bobbin case 6a.
An engagement hole 101 into which 5 fits is formed. When the bobbin case 6a is fitted into the inner hook 3a, the engagement protrusion 95 is elastically fitted into the engagement hole 101, and thus the bobbin case 6a is locked to the inner hook 3a. A bobbin 74 shown in FIG. 1 is housed in this bobbin case 6a.

FIG. 13 is a sectional view showing an inner pot 3b according to still another embodiment of the present invention, FIG. 14 is a sectional view taken from - in FIG. 13, and FIG. 16 is a partially cutaway front view of the bobbin case 6b, and FIG. 16 is a side view thereof. A locking member 102 having a projection 102a projecting inward is fixed to the inner peripheral surface of the inner hook 3b by spot welding. Bobbin case 6b
A locking hole 103 is formed in which the protrusion 102a of the locking member 102 fits. Projection part 1
02a elastically fits into the locking hole 3b of the bobbin case 6b, and the bobbin case 6b locks into the inner hook 3b.
is maintained. Note that, similarly to the above embodiment, a bobbin 74 is housed in this bobbin case 6b.

As described above, the rod 121 is driven by compressed air from the air pressure source, and the shaft hole 8 of the bobbin 74 is
5, the bobbin 74 and the bobbin cases 6, 6a are pushed apart to grip the bobbin 74 and move the gripping means 7 in a direction away from the inner hook. , 6b can be removed from the inner hooks 3, 3a, 3b. Thereby, there is no fear that the bobbin and bobbin case will fall during attachment and detachment, and the bobbin and bobbin case can be reliably attached and detached from the inner hook.

Effects According to the present invention, the fitting cylinder is fitted into the winding cylinder of the bobbin by the gripping means and is gripped together with the bobbin case, so the bobbin can be reliably gripped and held together with the bobbin case. It can be attached to and taken out from the inner pot. Moreover, since the inner hook is provided with a retaining member, the bobbin case can be locked into the inner hook, and therefore the bobbin inside the bobbin case is securely held without being separated from the inner hook. can do.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a perspective view of the gripping means 7, FIG. 3 is a sectional view of the inner hook 3, and FIG. 4 is viewed from the arrow A1 side in FIG. 3. 5 is a front view of the bobbin case 6, FIG. 6 is a side view seen from the arrow A2 side in FIG. 5, and FIG. 8 is a plan view showing an inner hook 3a according to another embodiment of the present invention, FIG. 9 is a sectional view of a part thereof,
FIG. 10 is a front view of the bobbin case 6a stored in the inner hook 3a, FIG. 11 is a side view thereof, FIG. 12 is a perspective view of the leaf spring 94, and FIG. 13 is a view of still another embodiment of the present invention. Cross-sectional view showing the inner pot 3b, No. 14
15 is a front view of the bobbin case 6b housed in the inner hook 3b, and FIG. 16 is a side view thereof. 1... Attachment/detaching device, 3, 3a, 3b... Inner hook,
4, 6, 6a, 6b...Bobbin case, 5...Chute, 7...Gripping means, 11...Mounting member, 7
4... Bobbin, 90... Removal prevention member, 93... Locking groove, 94... Leaf spring, 95... Engaging protrusion, 10
1... Engagement hole, 102... Locking member, 103...
Locking hole, 120... Single acting cylinder, 121... Rod, 122... Casing, 124... Fitting cylinder, 124a... Large diameter part, 124b... Small diameter part,
128...Coil spring.

Claims (1)

[Scope of Claims] 1. A bobbin having a pair of flanges and a right cylindrical winding tube that connects these flanges, and a shaft that projects toward the open end and is shorter than the winding tube of the bobbin. A notch is formed that extends in the axial direction of the inner hook and opens to the bottom side of the inner hook when it is installed inside the inner hook, and locking grooves are formed on both sides of this notch. a bobbin case having an insertion hole formed coaxially with the axis of the inner hook; and a retainer fixed to the inner peripheral surface of the inner hook, fitting into the notch and elastically locking in the locking groove. and a gripping means for attaching and detaching the bobbin housed in the bobbin case by driving the bobbin closer to and away from the inner hook together with the bobbin case, and the gripping means has a notch extending along the axial direction. a fitting cylinder which is formed, fits into the winding cylinder, has an outer diameter expanded/reduced in the radial direction, and has an inclined surface on its inner peripheral surface whose diameter expands in a direction away from the inner hook; A bobbin and a bobbin for a sewing machine, comprising: a drive member that is in contact with the inner hook and drives the inner hook to move forward/backward in the axial direction; and a fluid pressure cylinder that drives the drive member forward/backward in the axial direction of the inner hook. Case attachment/detachment device.