JPH0570483U - Overlock sewing machine safety device - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention is directed to a safety device for an overlock sewing machine capable of prohibiting the drive of the sewing machine motor not only when the looper cover is opened but also when the cloth waste cover is removed. For the purpose of provision. [Constitution] This invention comprises a looper cover 1 and a cloth waste cover 7 supported by an overlock sewing machine so as to be openable and closable,
When at least one of the both covers is in an open state, the cover is provided with a detection means for detecting this and outputting the prohibition signal. The detection means detects the drive prohibition signal by pressing the movable contact. A switch S1 for outputting and a switch actuating body 1 movable to a pressing position and a releasing position with respect to the movable contact portion when the looper cover is in a closed state.
2. When the cloth scrap cover is in the open state, it moves forward and backward in conjunction with the opening and closing of the looper cover, and the switch operating body is pushed to the pressing position.
The operation lever 16 moves the switch operating body to the release position when the cloth waste cover is closed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a safety device for an overlock sewing machine, which eliminates the risk of the overlock sewing machine being driven with the internal mechanism exposed.

[0002]

[Prior Art]

 FIG. 6 is a diagram showing a commonly used overlock sewing machine. As shown in the figure, on the front surface of the main body M of the overlock sewing machine, there is provided a looper cover 1 to which a cloth dust cover 7 for covering the looper drive mechanism and the like is attached. As shown in FIG. 7, on the inner surface of the looper cover 1, a hinge plate 2 and a hinge plate 8 are connected to a support shaft 3 fixed to the main body M through respective shaft insertion holes 2a. The fixing portion 8b of the plate 8 is fixed to the main body portion M by screws. As a result, the looper cover 1 can be moved in the axial direction (directions A and B) of the support shaft 3 and rotated about the support shaft 3 (rotation in the arrow C and D directions). When opening the looper cover 1 from the state shown in FIG. 6, temporarily move the looper cover 1 in the A direction to release the fitting state with the main body M, and then rotate the support shaft 3 in the C direction. It can be done by rotating to.

A cloth table 6 is provided on the side of the main body M. The cloth table 6 is hinged to the main body portion M at the end portion in the cloth feeding direction and can be opened and closed with respect to the main body portion M by rotating in the arrow E and F directions. As described above, in the overlock sewing machine, the looper cover 1 and the cloth base 6 can be opened and closed, and by opening these, the internal mechanism housed in the main body M can be exposed to perform maintenance and adjustment work. And so on.

However, it is extremely dangerous for the operator to drive the sewing machine motor with the internal mechanism exposed. Therefore, such a safety device as shown in FIG. Is provided. This safety device comprises a switch S1 for controlling driving stop of the sewing machine motor, and a switch actuating mechanism for actuating a movable contact S1a of the switch S1 according to opening / closing of the looper cover 1. This switch operating mechanism includes an operating pin 5 fixed to the looper cover 1 by a pin holding member 4 (see FIG. 7) and a cloth feed direction tip of the sewing machine main body M so that the looper cover 1 can be easily opened and closed. The double wire W is arranged from the rear surface to the cloth table 6 provided on the side of the main body M from the rear surface ahead of the main body M in the cloth feeding direction.

As shown in FIG. 9, the double wire W is composed of a hollow outer wire, W1 and an inner wire W2 inserted through the hollow outer wire. One end W2a of the inner wire W2 has a movable contact of the switch S 1. It is provided so as to oppose S1a, and the other end W2b is provided at a position where it can oppose the operating pin 5. Further, the inner wire W2 is designed such that the other end W2b thereof is always projected from the outer wire W1 by the spring Wb housed in the spring housing part Wa. When the looper cover 1 is closed, the operating pin 5 presses the one end W2a of the inner wire W2 of the double wire W against the biasing force of the spring Wb. The one end W2a projects toward the switch S1 and presses the movable contact S1a to turn on the switch S1. Therefore, the sewing machine motor is ready to be driven. In this state, if the sewing start switch (not shown) is turned on, the sewing machine motor will start driving.

When the looper cover 1 is opened, the end of the inner wire W2 and the operating pin 5 are separated from each other, so that the inner wire W2 moves inside the outer wire W1 by the urging force of the spring and the other end W2b releases the pressing of the movable contact S1a of the switch S1 to turn off the switch S1. As a result, the sewing machine motor is prohibited from being driven, and it is possible to prevent the sewing machine from being operated even if the foot pedal is accidentally applied.

[0007]

However, in the above-mentioned conventional safety device, the following points are not taken into consideration, and it is still insufficient as a safety device. That is, in the overlock sewing machine, the edge of the cloth is automatically cut by the cooperation of the upper knife and the fixed knife (not shown), but this cloth waste is prevented from entering the inside of the main body M. A cloth waste cover 7 is provided. This cloth waste cover 7 is slidably attached to the above-mentioned looper cover 1 and can be removed from the looper cover 1 by sliding it upward. By removing this, the needle plate part and the like can be cleaned and cleaned. When performing an inspection, the upper knife and the upper looper can be released and the cloth waste cover 7 can be inserted along the needle plate so as to be on the same plane and double chain stitching can be performed. Therefore, in the overlock sewing machine, although the internal mechanism is exposed even if the cloth waste cover 7 is removed, in the above conventional safety device, the sewing machine can be driven if the looper cover 1 is closed. Since the setting is made, if the foot pedal is pressed with the cloth dust cover 7 removed, a dangerous situation may occur in which the sewing machine is driven with the internal mechanism exposed, and the safety device Was insufficient.

This invention has been made in view of the above problems, and it is possible to prohibit the driving of the sewing machine motor not only when the looper cover is opened but also when the cloth dust cover is removed. The purpose of the present invention is to provide a safety device that can further improve the safety when driving an overlock sewing machine.

[0009]

[Means for Solving the Problems]

 This invention comprises a sewing machine motor for prohibiting the drive of an overlock sewing machine by an input drive prohibition signal, and a prohibition signal output means for outputting the drive prohibition signal. It is composed of a looper cover and a cloth dust cover that are openably and closably supported by the cover, and a detection means that detects the open state of at least one of the covers and outputs the prohibition signal. is there.

Further, the detection means may have the following configuration, for example. That is, the detection means includes a switch that outputs a drive prohibition signal by pressing the movable contact, and a looper cover that can be moved to a pressing position and a releasing position with respect to the movable contact portion of the switch when the looper cover is in a closed state. When the fixed switch operation body and the looper cover are opened / closed, the switch operation body is pushed to the open position when the cloth waste cover is open, and the switch operation body is released when the cloth waste cover is closed. And an actuating lever for moving to. In addition to the above, the detection means includes a first detector that outputs a first detection signal when the looper cover is in an open state, and a second detector that outputs a second detection signal when the cloth waste cover is in a closed state. It is also possible to provide two detectors and output the detection signal of each detector to the sewing machine motor as an inhibition signal.

[0011]

[Action]

 In the safety device of the overlock sewing machine having the above structure, if either the looper cover or the cloth dust cover is opened, the detection means detects it and sends a drive prohibition signal to drive the sewing machine motor. It is prohibited. Therefore, even if the internal mechanism is exposed such as the adjustment work performed by opening the looper cover, the risk of accidentally driving the sewing machine is eliminated and the safety of the overlock sewing machine is greatly improved.

[0012]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. In each figure, the same or corresponding parts as those shown in the above-mentioned prior art are designated by the same reference numerals. First, a first embodiment of a safety device for an overlock sewing machine according to the present invention will be described. In the overlock sewing machine to which this embodiment is applied, the looper cover 1 and the cloth waste cover 7 are provided in the main body M as in the case of the above-mentioned prior art. The details of are omitted. The safety device in this embodiment is constructed as shown in FIGS. In the figure, a hinge plate 2 similar to the conventional one is fixed to the looper cover 1, and a shaft insertion plate 11 as a support member is fixed to the hinge plate 2. Shaft insertion portions 11a and 11b are formed at both ends of the shaft insertion plate 11, and the operation shaft 12 (switch actuating body) is inserted therein so that it can be moved and rotated in the axial direction. ing. When the looper cover 1 is in the closed state, the one end 12a of the operating shaft 12 opposes the other end W2b of the inner wire W2 of the double wire W provided therein. ..

The actuating shaft 12 has a push spring 14 interposed between a spring bearing 13 fixed to the actuating shaft 12 and the shaft insertion portion 11a, so that the spring bearing 13 is always attached to the other shaft insertion portion 11b. It is urged to press. Then, when the spring bearing 13 is in pressure contact with the shaft insertion portion 11b and the one end portion 12a of the operating shaft 12 is most protruded in the B direction (hereinafter, the position of the operating shaft 12 in this state is referred to as an operating position). If the looper cover 1 is in the closed state, the one end 12a of the actuating shaft 12 enters the storage portion Wa of the double wire W, and the inner wire W2 is pressed and moved in the direction of the switch S1 against the spring Wb. It is like this.

A lever support portion 11c bent upward is formed on the shaft insertion plate 11, and an intermediate portion of the operating lever 16 bent in an L-shape is formed by the shaft 17 on the lever support portion 11c. It is rotatably supported. A cutout portion 16a is formed in the lower end portion of the operating lever 16, and a small diameter groove 12c formed in the operation shaft 12 is inserted into the cutout portion 16a. Reference numeral 18 denotes a pulling spring stretched between the actuating lever 16 and the shaft insertion plate 11, and biases the actuating lever 16 in the arrow I direction. The pulling spring 18 urges the operating lever 16 with a force larger than the urging force of the push spring 14 applied to the operating shaft 12.

On the other hand, a cloth waste cover 7 detachably attached to the looper cover 1 (although a substitute equivalent to the cloth waste cover is used only when double chain stitching is performed, it is included in the cloth waste cover hereinafter. Is formed on the back surface of the operating lever 16 when it is mounted on the looper cover 1 and pushes the upper end of the operating lever 16 downward, against the pulling spring 18. 16 is rotated in the J direction. The switch S1, the actuating shaft 12 fixed to the looper cover 1, the actuating lever 16 rotatable on the support member 11 to which the actuating shaft 12 is fixed, and the double wire W constitute a detecting means. The detection means, the looper cover 1 and the cloth waste cover 7 constitute a prohibition signal output means.

FIG. 1 shows a state in which the looper cover 1 is in the closed state and the cloth waste cover 7 is attached to the looper cover 1 in the first embodiment of the present invention configured as described above. In this state, the one end 12a of the actuating shaft 12 penetrates into the storage portion Wa of the double wire W and presses the inner wire W2 toward the switch S1, so that the one end W2a of the inner wire W2 moves the switch S1. The contact S1a is pressed to cause the switch S1 to output an ON signal as a non-driving prohibition signal. As a result, the sewing machine motor that has received the ON signal is ready to drive the motor, and the sewing machine motor is driven when the sewing start switch (not shown) is actuated. The ON signal may be input to the sewing machine motor drive circuit MMD to drive the sewing machine motor.

Here, when the looper cover 1 is moved in the arrow A direction to open the looper cover 1, the shaft insertion plate 11 moves in the A direction together with the hinge plate 2 (see FIG. 3). At this time, since the spring bearing 13 is in contact with the shaft insertion portion 11b of the shaft insertion plate 11, the operating shaft 12 also moves in the direction A together with the shaft insertion plate 11. As a result, the pressing force of the actuating shaft 12 toward the switch S1 against the inner wire W2 is released, and the double wire W is moved in the anti-switch S1 direction in the outer wire W1 by the spring Wb housed in the housing Wa. The other end W2b is separated from the movable contact S1a of the switch S1. Therefore, the switch S1 outputs an OFF signal as a drive prohibition signal, and the sewing machine motor receiving this signal is in the drive prohibition state, and the motor is not driven even when the foot pedal (hereinafter referred to as the sewing start switch) is actuated. Absent. The OFF signal may be sent via the motor drive circuit.

Further, when the cloth waste cover 7 is removed from the looper cover 1 with the looper cover 1 closed, the state shown in FIG. 4 is obtained. That is, when the cloth waste cover 7 is slid upward, the pressing force applied to the upper end of the operating lever 16 is released by the projecting portion 7a of the cover 7, so that the operating lever 16 is provided with the pulling spring 18. The urging force causes the shaft 17 to rotate in the I direction, and the lower end thereof abuts the rear end of the small diameter groove 12c to press the operating shaft 12 in the G direction.

At this time, the pressing force applied to the actuating shaft 12 by the pulling spring 18 is larger than the biasing force of the pushing spring that biases the actuating shaft 12 in the H direction. It moves in the A direction according to the urging force. As a result, the one end 12a of the actuating shaft 12 is pulled out from the housing Wa of the double wire W, and the pressing force on the inner wire W2 is released. Therefore, the inner wire W2 is moved in the direction opposite to the switch S1 by the spring Wb, and the other end W2b releases the pressing force on the movable contact S1a. Therefore, even when the cloth waste cover 7 is removed in this way, the drive prohibition signal (OFF signal) is output from the switch S1 and the motor drive prohibition state is entered via the sewing machine motor or the motor drive circuit MMD. Even if the sewing start switch is actuated, the risk of driving the sewing machine is eliminated.

As described above, in this embodiment, if any one of the looper cover 1 and the cloth waste cover 7 is opened, the driving of the sewing machine motor is prohibited, and therefore the main body portion M of the sewing machine is prohibited. With the internal mechanism stored inside exposed, the danger of driving the sewing machine is completely eliminated, and work safety is greatly improved.

Next, a second embodiment of the present invention will be described with reference to FIG. In each drawing, the same or corresponding parts as those of the above-described embodiment and the prior art are designated by the same reference numerals, and detailed description thereof will be omitted. In the second embodiment, the actuating lever 16 in the first embodiment is deleted, and instead of this, an ON / OFF signal is output to the upper part of the shaft insertion plate 11 according to the opening / closing of the cloth waste cover 7. A micro switch S2 is provided.

That is, when the cloth switch cover 7 is attached to the looper cover 1 in the closed state, the micro switch S2 presses the movable contact S2 by the protrusion 7a of the cloth switch cover 7 and outputs an ON signal. When the cloth waste cover 7 is removed and the pressing force on the movable contact S2a is released, an OFF signal is output. The respective output signals of the micro switch S2 and the switch S1 operated by the double wire W are input to the inhibition signal output circuit 20 connected to the preceding stage of the motor drive circuit MMD. The prohibition signal output circuit 20 is a logical sum output circuit for the outputs of the switches S1 and S2. When the OFF signal is output from at least one of the switches S1 and S2, the drive prohibition signal is output. Outputs an OFF signal. In this embodiment, the switch S1, the micro switch S2 and the prohibition signal output circuit 20 constitute a detecting means.

The second embodiment of the present invention is configured as described above, and when the looper cover 1 is in the open state, the ON signal is output from the switch S1 as in the first embodiment. Therefore, the sewing machine motor that receives this or the sewing machine motor via the sewing machine motor drive circuit MMD is in the drive prohibited state, and even when only the cloth dust cover 7 is opened, the OFF signal is output from the switch S2. Therefore, the sewing machine motor or the sewing machine motor via the sewing machine motor drive circuit MMD is in the drive prohibited state. That is, the sewing machine motor or the motor drive circuit MMD can be driven only when the looper cover 1 and the cloth dust cover 7 are all closed. Therefore, also in the second embodiment, the same risk prevention effect as in the first embodiment can be expected.

Further, in each of the above-described embodiments, the switches S1 and S2 that are turned on and off by pressing and releasing the movable contact are used as detection means for detecting the opening / closing of the looper cover 1 or the cloth waste cover 7. However, instead of this, a non-contact type sensor such as an optical sensor or a magnetic sensor can be used, and the present invention is not particularly limited to the above embodiment.

[0025]

[Effect of the device]

 As described above, the safety device for an overlock sewing machine according to the present invention has a looper cover and a cloth dust cover which are openably and closably supported by the overlock sewing machine and when at least one of the both covers is in an open state. A detection means that detects this and outputs a drive prohibition signal, and a sewing machine motor that receives this drive prohibition signal and prohibits drive are provided to detect not only when the looper cover is opened but also when the cloth dust cover is opened. It is also possible to prohibit the driving of the sewing machine, avoid the risk of the sewing machine being driven with the internal mechanism exposed, and obtain an excellent function as a safety device.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of a first embodiment of the present invention.

FIG. 2 is a side view with a part of the one shown in FIG. 1 omitted.

FIG. 3 is a perspective view showing a main part of FIG. 1 with only the looper cover opened.

FIG. 4 is a perspective view showing a main part of the apparatus shown in FIG. 2 with only the cloth waste cover opened.

FIG. 5 is a perspective view showing a main part of a second embodiment of the present invention.

FIG. 6 is a perspective view showing a conventional overlock sewing machine.

FIG. 7 is an enlarged side view showing the attached state of the looper cover shown in FIG. 6 and the configuration around it.

FIG. 8 is an explanatory perspective view schematically showing a safety device for a conventional overlock sewing machine.

FIG. 9 is a partially cutaway perspective view showing a double wire and a switch used in the related art and the above embodiment.

[Explanation of symbols]

 M Main unit S1a Movable contact S1 switch (first detector) S2 switch (second detector) 1 Looper cover 7 Cloth dust cover 12 Actuating shaft (switch activator) 16 Actuating lever

Claims (3)

[Scope of utility model registration request] 1. A sewing machine motor for prohibiting driving of an overlock sewing machine according to an input drive prohibition signal, and prohibition signal output means for outputting the drive prohibition signal, wherein the prohibition signal output means is overlocked. When a looper cover and a cloth waste cover that are openably and closably supported by the sewing machine and at least one of the both covers is in an open state,
A safety device for an overlock sewing machine, comprising: a detection unit that detects this and outputs the prohibition signal. 2. The detecting means is movable to a pressing position and a releasing position with respect to the movable contact portion when a switch for outputting a drive inhibition signal by pressing the movable contact and a looper cover is in a closed state. The switch operating body fixed to the looper cover and the switch operating body that moves forward and backward in conjunction with the opening and closing of the looper cover, pushes the switch operating body to the pressing position when the cloth dust cover is open, and the switch operating body when the cloth dust cover is closed. The safety device for an overlock sewing machine according to claim 1, further comprising: an operating lever that moves the lever to a release position. 3. The detection means outputs a first detection signal that outputs a first detection signal when the looper cover is in an open state, and outputs a second detection signal when the cloth dust cover is in a closed state. The safety device for an overlock sewing machine according to claim 1, further comprising a second detector, wherein the detection signal of each detector is output to the sewing machine motor as an inhibition signal.