JPH088779Y2 - Sewing machine cloth presser - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a cloth pressing device for pressing a base cloth under a needle in synchronization with the driving of a sewing needle of a sewing machine.

[Prior Art and its Problems] When work is performed below the sewing needle, for example, when setting the base cloth before the start of sewing, the work clamp is an obstacle to the work. In addition, since the needle bar case is located above the cloth retainer, it is difficult to raise the cloth retainer sufficiently to secure a working space.

[Means for Solving the Problems] In order to solve the above problems, the cloth pressing device for a sewing machine according to the present invention is configured as follows.

That is, a downward force is constantly applied by the air cylinder to the operating rod having the cloth retainer fixed to the lower end portion thereof, and the driving mechanism of the sewing machine head opposes the force received by the operating rod from the air cylinder. By lifting upward, the cloth presser is reciprocated in synchronization with the driving of the sewing needle.

The air cylinder employs a return type in which the operation rod can be operated upward by exceeding the stroke at the time of sewing by sewing by switching the air supply. Further, the guide body for guiding the vertical movement of the operating rod is formed with a cam groove in which a part of the operating rod is engaged. Moreover, when the operating rod moves upward beyond the stroke at the time of sewing with the sewing machine, the cam groove causes the operating rod to rotate so as to rotate the cloth presser in the direction of retracting from the bottom of the sewing needle. It is set to give shape.

[Operation] According to this configuration, by switching the air supply to the air cylinder, the operating rod can be operated upward beyond the stroke at the time of sewing with the sewing machine.
Then, due to the movement of the operating rod, the cloth presser is raised while turning in the direction of retreating from below the sewing needle.

This is different from the case where the cloth presser is raised straight, for example, the cloth presser can be retracted to a position avoiding the needle bar case, and a sufficient working space under the needle can be secured.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows the structure of the sewing machine head of the quilting sewing machine, and FIG. 2 shows a front view seen from the left side of FIG. In FIGS. 1 and 2, an air cylinder 30 is fixed to the head housing 10 by an L-shaped bracket 31. This air cylinder 30
A reciprocating type in which the operating rod 32 can be reciprocated in the vertical direction of the sewing machine head (vertical direction in FIGS. 1 and 2) is used. Therefore, the air cylinder 30 is provided with two ports 30a and 30b, and air is normally supplied to the upper port 30a to constantly apply a downward force to the operating rod 32.

FIG. 5 shows an outline of air supply to the air cylinder 30. As is apparent from FIG. 5, the air sent from the predetermined air source 62 is selectively supplied to either one of the ports 30a and 30b through the pressure regulating valve 64 and the solenoid valve 60 for switching the air supply direction. It is supposed to be done. Ie solenoid valve 60
Can supply air to the upper port 30a of the air cylinder 30 when the power is off (state of FIG. 5), and can supply air to the lower port 30b when the power is on.

In FIGS. 1 and 2, a cloth retainer 34 is fixed to the lower end of the operating rod 32. As is apparent from FIG. 3 whose plan view is shown, this cloth retainer 34 is provided with a circular dish-shaped portion 35 and an arm portion 36 formed integrally therewith. The end is the operating rod
It is fixed to the lower end of 32. A needle hole 37 through which a sewing needle 54, which will be described below, can be inserted is formed at the center of the dish-shaped portion 35.

Similarly, in FIG. 1 and FIG. 2, a needle bar case 50 is provided on the front side of the head housing 10,
It is attached to 10 so that it can be slid in the left-right direction in FIG. Inside the needle bar case 50, for example, three needle bars 52 are incorporated so as to be vertically movable,
A sewing needle 54 is attached to the lower end of each needle bar 32. Then, an operating force for sewing is applied to one needle bar (the rightmost needle bar in FIG. 2) 52 selected by sliding the needle bar case 50.

A drive shaft 12 is arranged in the head housing 10 in a penetrating state. Rotation is transmitted to the drive shaft 12 from a drive source (not shown) such as a motor, and this rotation force is transmitted to one of the needle bars 52 as a drive force for sewing through a mechanism not shown. As is well known. Apart from this, the rotational force of the drive shaft 12 is also used as a drive mechanism for reciprocating the cloth pressing member 34 in synchronization with the driving of the needle bar 52. That is, the cam 14 is fixed on the shaft of the drive shaft 12, and the head housing 10 is provided with an interlocking lever 16 interlocked with the rotation of the cam 14.

As is apparent from FIG. 4, the interlocking lever 16 has a shaft 18 whose substantially middle portion is fixed to the head housing 10.
It is rotatably supported by. This interlocking lever 16
Is provided with a cam follower 20 capable of contacting the outer periphery of the cam 14, and the other end (the left end in FIG. 1) has an upper end of the actuating rod 32. The parts are connected. A torsion spring 19 is attached to the outer circumference of the shaft 18, and the torsion spring 19
Urges the interlocking lever 16 counterclockwise in FIG. As a result, the cam floor 20 is constantly pressed against the outer circumference of the cam 14.

On the other hand, the coupling portion between the interlocking lever 16 and the operating rod 32 is configured such that the member 33 fixed to the operating rod 32 is received from below by the receiving portion 22 of the interlocking lever 16. Therefore, when the interlocking lever 16 operates in accordance with the rotation of the cam 14, the operating rod 32 is lifted upward against the downward force received from the air cylinder 30, which causes the cloth presser 34 to move. It moves back and forth. It is also possible to independently actuate the operating rod 32 independently of the interlocking lever 16 in the upward direction.

The operating rod 32 is a cylindrical guide body 40 fixed to the upper end surface of the air cylinder 30 so as to be coaxial therewith.
The vertical movement is guided by.
A cam groove 42 is formed on the outer circumference of the guide body 40 along the vertical direction thereof. A pin 38 fixed to a part of the operating rod 32 is engaged with the cam groove 42.

As is apparent from FIG. 6 which shows the cam groove 42 in the unfolded state, the operating rod 32 within the range of the stroke S1 corresponding to the vertical stroke of the presser foot 34 at the time of sewing with the sewing machine.
From a portion extending in parallel with the axis of, a portion extending upward from here in the range of stroke S2 and extending in an inclined shape while being displaced by a rotation angle θ1 in the circumferential direction, and a portion extending from here in the range of angle θ2 in the circumferential direction. It is configured.

By the pin 38 of the operating rod 32 being guided in the cam groove 42 of the guide body 40, when the operating rod 32 operates beyond the stroke S1 during normal sewing to a range of the stroke S2, the operating rod 32 moves 6th around the axis
It rotates by θ1 in the figure. As a result, the dish-shaped portion 35 of the cloth presser 34 is raised while retracting from below the sewing needle 45 in the turning direction.

In the quilting sewing machine having the above structure, the needle bar 52
The operation of the presser foot 34 that reciprocates in the vertical direction in synchronization with the driving of the above will be described. First, the rotation of the cam 14 fixed to the drive shaft 12 causes the interlocking lever 16 to repeat the reciprocating rotation operation through the cam floor 20 with the shaft 18 as a fulcrum. On the other hand, the operating rod 32, to which the cloth retainer 34 is fixed, is constantly subjected to downward urging force by the action of the air supplied to the port 30a of the air cylinder 30. When the operating rod 32 is lifted upward by the operation of the interlocking lever 16, the cloth presser 34 is moved to the first position.
It reciprocates within the range from the position indicated by the solid line shown in FIGS. 2 and 2 to the position indicated by the imaginary line A. The stroke of the operating rod 32 at this time corresponds to the stroke S1 shown in FIG.

Now, for example, in the work such as setting the base cloth before the start of sewing, the solenoid valve 60 shown in FIG. 5 is turned on and air is supplied to the port 30b of the air cylinder 30. As a result, the operating rod 32 is pushed further upward beyond the stroke at the time of sewing. At this time, the pin 38 of the operating rod 32 is engaged with the cam groove 42 of the guide body 40.
On the other hand, it moves beyond the stroke S1 shown in FIG. 6 to the range of the stroke S2.

As a result, the operating rod 32 rotates about its axis by the angle θ1 in FIG. 6 (about 50 degrees in this embodiment). Accordingly, the work clamp 34 is moved from the lower position of the sewing needle 54 during sewing to the first position.
Ascending while turning to the position of the virtual line B shown in FIGS. That is, the presser foot 34 is retracted to a position avoiding the needle bar case 50. This allows the needle bar case 50
A large work space below is secured, and work such as setting the base cloth can be performed easily.

Depending on the work, the drive source of the quilting sewing machine and the drive of the air source 62 to the air cylinder 30 may be stopped. In this case, the work clamp 34 at the position of the virtual line B shown in FIGS. 1 to 3 is manually rotated to the position of the virtual line C shown in FIGS. 1 and 3. Let At this time, the pin 38 of the operating rod 32 is a guide member.
The angle θ2 shown in FIG. 6 with respect to the cam groove 42 of 40
Rotate only (about 40 degrees in this embodiment) to lock the cam groove 42.
Falls to 43. As a result, the presser foot 34 is locked at the position of the imaginary line C shown in FIGS. 1 and 3, and is kept in that state even when the drive of the air source 62 to the air cylinder 30 is stopped.

In order to return the work clamp 34 at the position of the imaginary line C shown in FIGS. 1 and 3 to the position of the phantom line B or the position of the solid line, the work clamp 34 is manually lifted a little and the operating rod 32 The pin 38 is removed from the locking portion 43 of the cam groove 42. In this state, the cloth presser 34 may be rotated in the original direction by the angle θ2 shown in FIG.

The function according to the present embodiment is effective not only in the cloth presser of the quilting sewing machine shown in the drawings but also in the cloth presser of a general fabric sewing machine.

[Advantage of the Invention] In this invention, by simply switching the air supply to the air cylinder that applies a force in the direction of pressing the base cloth to the operating rod to which the cloth presser is fixed, the cloth presser is positioned above it. The needle bar case can be retracted to an upper position. Therefore, a sufficient working space under the needle can be secured, and for example, the work of setting the base cloth before the start of sewing becomes easy.

[Brief description of drawings]

The drawings show one embodiment of the present invention. Fig. 1 is a side view of a sewing machine head of a quilting sewing machine, Fig. 2 is a front view seen from the left side of Fig. 1, Fig. 3 is a plan view of a presser foot, and FIG. 5 is a plan view showing the relationship between the operating rod and the interlocking lever, FIG. 5 is a schematic view showing an air supply system for the air cylinder, and FIG. 6 is an explanatory view showing the cam groove in a developed state. 12 …… Drive shaft 14 …… Cam 16 …… Interlocking lever 30 …… Air cylinder 32 …… Actuating rod 34 …… Cloth retainer 40 …… Guide body 42 …… Cam groove 54 …… Sewing needle

Claims (1)

[Scope of utility model registration request] 1. An air cylinder always applies a downward force to an operating rod having a cloth presser fixed to a lower end thereof, so as to resist the force received from the air cylinder by the drive mechanism of a sewing machine head. A cloth presser device of the type in which the cloth presser is reciprocated in synchronization with the driving of a sewing needle by lifting it upward, wherein the air cylinder is a stroke when sewing the operating rod by switching the air supply. It is a return type that can be operated in the upward direction over the above, and the guide body for guiding the vertical movement of the operating rod is formed with a cam groove in which a part of the operating rod is engaged. When the operating rod moves upward beyond the stroke at the time of sewing with the sewing machine, the operating rod is turned so as to pivot in a direction of retracting the work clamp from below the sewing needle. Presser unit of the sewing machine which is set in a shape to provide a rotation.