JPS6029993Y2 - Sewing machine arm support device - Google Patents

Description

[Detailed explanation of the invention] This invention has an arm that is rotatable around a horizontal axis at the bottom of the arm that has a bed for the oil pan fixed to the sewing machine table.The arm can be adjusted from the laid down position for sewing work. The present invention relates to a support device for a sewing machine arm, which allows the arm to be moved to an upright position, and fixes the arm to an oil pan in both a collapsed position and an upright position.

Conventionally, this type of support device has been equipped with different devices to fix the arm to the oil pan when the arm is in the down position and in the upright position, so it is necessary to operate the corresponding device each time. However, it not only takes time and effort and reduces work efficiency, but also has the disadvantage of increasing costs due to the large number of parts.

The object of this invention is to provide a device capable of fixing an arm in a laid down position and an upright position with respect to an oil pan using a single device, thereby eliminating the above-mentioned drawbacks.

An embodiment of this invention will be described with reference to FIGS. 1 to 4.

Reference numeral 1 designates an oil receiver, which has a bearing portion 2 projecting upwardly at its left end, and has two protrusions 3.3 on its right side.
Although not shown, this oil pan 1 is fixed to the upper surface of the sewing machine table.

Reference numeral 4 denotes a sewing machine arm, which is integrally provided with a bed incorporating a hook and a feed mechanism (not shown), and whose lower left end is rotatably connected to the bearing portion 2 of the oil pan 1 by a horizontal shaft 5. A notch 6 opening at the lower end surface is formed.

A fixing plate 7 is fixed at both ends to the end face of the projection 3 of the oil pan 1 with screws 8, 8, and has an inclined groove 9 formed in its center.

Reference numeral 10 designates a link, one end of which is rotatably connected to the arm 4 by a step screw 11 having a horizontal axis, and a roller 12 serving as a movable portion is loosely fitted through an inclined groove 9 and fixed at the other end. Screw 13 through a washer (not shown) on the opposite side of plate 7
Fix it by.

14 is a locking body whose base is connected to the fixing plate 7 with a stepped screw 1.
5, a notch 16 that is rotatably supported and recessed downward from the center of the upper end, a push-up surface 17 located in the movement path of the roller 12 that is loosely fitted in the inclined groove 9, and an engagement that is a first engagement part. A long hole 20 is formed which has a claw portion 19 consisting of a surface 18 and is bent as shown in FIG.

The locking body 14 is attached to the arm 4 as shown in FIG.
When the rollers 12 of the link 10 and the engagement surface 17 of the claw portion 19 are engaged with each other in the upright position, the center axis of the step screw 15 as the center axis of rotation of the locking body 14 is aligned with the step at the upper end of the link 10. It is located on a straight line connecting the center of the screw 11 and the roller 12, and the engaging surface 17 of the claw portion 19 is substantially orthogonal to the straight line connecting the center axis of the step screw 15 and the roller 12.

21 is a locking lever that is a locking body, and has an upper end portion that has an engagement surface 21a that is a second engagement body that is parallel to the horizontal axis 5;
An arm portion 21b extends inward from the intermediate portion so as to engage with the cutout portion 16 of the locking body 14, and the lower end portion is bent at right angles in the horizontal direction to project outward from the cutout 6 of the arm 4. The operating portion 21C is rotatably supported by the base shaft 22 with respect to the upper end of the locking body 14, and the base shaft 22 projects inward.

A pin 23 and an arm portion 21b protruding inward from the lower end of the fixed plate 7
The coil spring 24, which is hung between the locking lever 21 and the locking lever 21, normally presses the lower surface of the arm portion 21b of the locking lever 21 against the upper end surface of the cutout portion 16 of the locking body 14 due to its elastic force. Then, a clockwise acting force is applied to the locking body 14 via the base shaft 22, and the protruding lower end of the base shaft 22, which is a stopper, is pressed against the upper end of the fixing plate 7, and the claw portion 19 is pressed as shown by the solid line in FIG. It is maintained on the movement path of the roller 12.

The locking lever 21 rotates clockwise against the elastic force of the coil spring 24 that pushes the contact portion 21C of the locking lever 21 downward.

Reference numeral 25 denotes a hook which is a protrusion, and is arranged so as to extend downward inside the lower part of the sewing machine arm 4, and its tip is connected to the locking lever 2.
A hook portion 25a that engages with the first engaging surface 22 is formed.

This invention has the above-mentioned configuration, and FIG. 3 shows a state in which the arm 4 is in an upright position when adjusting the inside of the sewing machine arm 4.

In this state shown in FIG. 3, the rollers 12 at the lower end of the link 10
The lower end along the inclined groove 9 is locked by the engagement surface 18 of the locking body 14, and is relative to the straight line connecting the step screw 15 as the rotation center axis of the locking body 14 and the axis of the roller 12. Since the retaining surfaces 18 are substantially orthogonal, even if the rollers 12 of the link 10 receive a downward force along the inclined groove 9 due to the weight of the arm 4 or the pressing force of the arm 4 in the direction of collapse, the effect will not be affected. Since the force does not become a turning moment to turn the locking body 14,
Arm 4 will not fall down.

Furthermore, even if a pressing force is applied to the link 10 with the step screw 11 as the center, the roller 12 is restrained by the inclined groove 9, so it does not rotate, and the arm 4 is reliably maintained in the upright position shown in FIG. be done.

To bring the arm 4 to the collapsed position from the state shown in FIG. When the locking body 14 is raised to the position indicated by the chain line and rotated upward via the arm portion 21b and the base shaft 22 of the locking lever 21 to release the locking of the roller 12 by the engagement surface 18, the arm 4 is It rotates clockwise around the shaft 5 due to its own weight, and as a result, the roller 12 at the lower end of the link 10 slides downward on the inclined groove 9, and after the roller 12 passes through the claw portion 19, the operating portion 21
When C is released, the lower surface of the arm portion 21b of the locking lever 21 presses the notch 16 of the locking body 14 due to the elastic force of the coil spring 24, and the locking body 14 returns to its original position.

At this time, the hook 25 descends from above, pushes away the engagement surface of the locking lever 21 with its tip, rotates the locking lever 21 clockwise against the elastic force of the coil spring 24, and then the hook 25 is lowered, and the lower end of the arm 4 comes into contact with the upper end of the oil pan 1 as shown in FIG. The joint arm 4 is locked to the oil receiver 1.

Further, in order to bring the arm 4 into the upright position from the collapsed position of the arm 4 shown in FIG. When the arm 4 on the side opposite to the position of the shaft 5 of the arm 4 is lifted from the state shown in FIG. As it slides upward, the roller 12 pushes up the push-up surface 17 of the claw portion 19 and rotates the locking body 14 about the stepped screw 15 against the coil spring 24 as shown by the two-dot chain line in FIG.

When the roller 12 is on the left side of the engagement surface 18 of the claw part 19, the locking body 14 is restored by the elastic force of the coil spring 24, and each part becomes as shown in FIG. 3, and the arm 4 is maintained in the upright position. be done.

Next, a second embodiment will be explained with reference to FIGS. 5 and 6.

The locking body 14 rotatably supports the base of the locking body 14 with respect to the fixing plate 7 by a step screw 15, and bends the lower left end at right angles in the horizontal direction, and extends the locking body 14 from the notch 6 of the arm 4 to the outside of the arm. an operating portion 14a protruding toward the right; a claw 26 consisting of a push-up surface 14b located in the moving path of the roller 12 loosely fitted in the inclined groove 9 at the lower center end; and an engaging surface 14C serving as a first engaging portion; An engagement surface 14d serving as a second engagement portion is formed at the lower end.

The locking body 14 is provided with a pin 27 which is a protrusion extending inward at the center thereof, and is rotated by the elastic force of a coil spring 24 stretched between the pin 27 and a pin 23 protruding from the inside of the fixing plate 7. Pin 27 always receives clockwise rotational force.
When the pin 27 comes into pressure contact with the upper end surface of the fixed plate 7, the pin 27 acts as a stopper and restricts the clockwise rotation of the locking body 14, and the push-up surface 14b of the locking body 14 is placed on the movement path of the roller 12 of the inclined groove 9. Located in

When the sewing machine arm 4 is in the upright position as shown in FIG. 5, the locking body 14 is in the position shown by the solid line in FIG.
2 is engaged with the engaging surface 14C of the pawl 26 to prevent clockwise rotation of the sewing machine arm 4 and hold the sewing machine arm 4 in the upright position.

At this time, the stepped screw 15 is located on a line connecting the central axes of the stepped screw 11 and the screw 1, and the engaging surface 14C of the locking body 14 is shaped in a direction perpendicular to the line.

With the sewing machine arm 4 in the upright position shown in FIG. 5, grip the operating part 14a of the locking body 14 with your fingers and rotate it counterclockwise against the elastic force of the coil spring 24 to the position indicated by the solid line in FIG. , move to the position indicated by the two-dot chain line, release the engagement between the roller 12 and the engagement surface 14G of the locking body 14, and then rotate the sewing machine arm 4 from the upright position to the laid down position while supporting it with your hand. 12 begins to descend without sliding on the inclined groove 9, and when it is located on the right side of the inclined groove 9, when the operating part 14a of the locking body 14 is released from the finger, the elastic force of the coil spring 24 causes the downward movement as shown in FIG. Return to position.

Step screw 1 for pivotally connecting one end of link 10 to sewing machine arm 4
1 projects horizontally inward, and when the sewing machine arm 4 rotates from the upright position to the laid down position, the step screw 11
is lowered, its lower end engages and slides on the left upper surface of the locking body 14, and the locking body 14 is rotated counterclockwise against the elastic force of the coil spring 24, as shown in FIG. After moving from the position indicated by the solid line to the position indicated by the two-dot chain line, when the locking body 14 further descends and leaves the side surface of the locking body 14, the locking body 14 rotates clockwise due to the elastic force of the coil spring 24 and moves to the fifth position. Return to the position indicated by the solid line in the figure.

As a result, the upper end of the step screw 11 is connected to the engagement surface 14 of the locking body 14.
d and when the sewing machine arm 14 is lifted, the pin 27 of the locking body 14 restricts the clockwise rotation of the locking body 14 and prevents the upward force acting on the step screw 11. , the sewing machine arm 4 is fixed in the laid down position.

At this time, the engagement surface 14d of the locking body 14 is perpendicular to a line connecting the central axis of the stepped screw 15 and the central axis of the stepped screw 11 of the locking body 14.

To move the sewing machine arm from the laid down position to the upright position, hold the operating part 14a of the locking body 14 between your fingers, rotate it counterclockwise, and move it from the position shown by the solid line in Figure 5 to the position shown by the two-dot chain line. Then, the engagement between the engaging surface 14d of the locking body 14 and the shoulder screw 11 is released, and the enabling screw 11 engages with the upper left side surface of the locking body 14.

In this state, when the sewing machine arm 4 is lifted by hand and rotated from the collapsed position to the upright position, the roller 12 slides upward on the inclined groove 9 and pushes up the push-up surface 14b of the locking body 14 from below.
After the locking body 14 is rotated counterclockwise against the elastic force of the coil spring 24 and moved from the position shown by the solid line in FIG. When the locking body 14 leaves the upper surface 14b and is positioned on the left side of the inclined groove 9, the locking body 14 rotates clockwise due to the elastic force of the coil spring 24 and returns to the position shown by the solid line in FIG. The mating surface 14C is roller 1
2, the sewing machine arm 4 is maintained in the upright position.

In the illustrated embodiment, the inclined groove 9 and the locking body 14 are provided on the fixed plate 7 fixed to the oil pan 1, but the slope groove 9 and the locking body 14 may also be provided directly on the oil pan 1. It is possible, and it is also possible to rotatably provide one end of a link in which the inclined groove 9 and the locking body 14 are provided on the arm 4 side.

Further, although the coil spring 24 is shown as the rotational force for restoring the locking body 14, the weight of the locking body 14 may be used as the rotational force.

Further, in the illustrated embodiment, the roller 12 is slidably and loosely fitted into the inclined groove 9, but the roller 12 may be used as a general shaft, or the roller 12 may be slid with respect to the oil pan 1 using the inclined groove 9 as the axis. The lower end of the link 10 can also be connected to the lower end of the link 10.

Furthermore, the claw portion 19 of the elongated hole 17 of the locking body 14 may be provided so as to engage the roller 12 from below instead of from above.

Furthermore, in the illustrated embodiment, the position of the stepped screw 15 at the center of rotation of the locking body 14 is on the straight line connecting the center axis of the stepped screw 11 at the upper end of the link 10 and the roller 12 at the lower end. This position may be in the vicinity of the above-mentioned straight line, and the engaging surface 18 of the locking body 14 when the arm 4 is locked in the upright position is aligned with the straight line connecting the center axis of the step screw 15 and the roller 12. Although the angle is approximately perpendicular to the angle, the angle is not limited to this angle, and may be an angle close to this angle.

As described above, in this invention, when the arm 4 is in the upright position and adjustment work is being performed inside the arm 4, even if a force is applied to the arm 4 in the direction of the collapsed position, the engaging surface 18 of the locking body 14 In addition to reliably preventing movement in the direction, the inclined groove 9 serves as a guide even if an external force is accidentally applied to the link 10.
Since the lower end of the link 10 is not displaced and the arm 4 is locked in the upright position, an accident caused by the arm 4 unexpectedly falling from the upright position to the down position can be prevented.

Furthermore, when the arm 4 is brought down from the upright position to the laid down position, the protrusion 11.25 provided on the arm 4 descends, rotates and retracts the locking body 14 located in its movement path, and then automatically Then, return the locking body 14.21 to its original position and remove the protrusion 1.
1 and 25 are engaged with the engaging surfaces 14d and 21a of the locking body 14.21, and even if a force is applied from the collapsed position to the upright position, the locking body 14.21 will not close to the stopper 27.21b.
This prevents rotation and securely locks the arm 4 in the laid down position, which not only fixes the arm 4 and improves the efficiency of sewing work, but also allows the arm 4 to be locked in the upright position and the laid down position. This can be done with one device, which reduces labor and improves work efficiency, and has the effect of reducing costs because the number of parts is small.

In addition, since the operating parts 14a and 21C of the locking body 14.21 are located outward from the lower surface of the arm 4, there is no accident of fingers being caught between the lower surface of the arm and the upper surface of the oil pan 1, resulting in excellent safety. There is.

[Brief explanation of the drawing]

Figure 1 is a side view of the entire sewing machine with the arm in the upright position, Figures 2 to 4 are the first embodiment with some parts omitted, Figure 2 is a perspective view, and Figure 3 is a perspective view. is an explanatory diagram of the operation with the sewing machine arm in the upright position, FIG. 4 is a state diagram with the sewing machine arm in the down position, and FIGS. 5 and 6 show the second embodiment, with the sewing machine arm in the upright position and the down position. The position is partially omitted.

Claims (1)

[Scope of Claim for Utility Model Registration] In a sewing machine in which the lower part of an arm having a bed is rotatably connected around a horizontal axis to an oil pan fixed to a sewing machine table, so that the arm can be moved between an upright position and a laid down position. The oil pan is provided on either side of the arm and has a guide part 9 inclined with respect to the horizontal plane, and the oil pan on the side where the guide part is not provided is connected to the arm so as to be rotatable about the horizontal axis. , a link 10 having a moving part whose other end is connected to the guide part and which moves along the guide part by displacing the arm between an upright position and a collapsed position; and an oil pan on the side where the guide part is provided at the base. An operating part 14 rotatably supported on the arm and located outside the oil pan.
a, 21c, and a first engaging part l 4 c, 1 that engages with the moving part of the link and can lock and release the arm in the upright position.
8, engages a part of the arm and locks the arm in the laid down position.
A support device for a sewing machine arm, comprising: a locking body 14.21 in the form of a second engaging portion 14dt21a that can be released.