JPH0871286A - Silencing structure for sewing machine - Google Patents

Abstract

PURPOSE: To provide a silencing structure for a sewing machine reducing the impact sound generated when the feed is switched and giving no uncomfortableness to a worker. CONSTITUTION: A feed adjusting screw 11 is operated via an operation dial 12, the layout position of a feed regulator 3 is finely adjusted, and the fabric feed quantity is adjusted. When the fabric feeding direction is switched to forward and reverse, the feed regulator 3 collides with the feed adjusting screw 11, the impact is transferred to the operation dial 12 via the feed adjusting screw 11, and the impact can be mitigated or damped by a member made of rubber or elastomer and inserted between the operation dial 12 and feed adjusting screw 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing machine capable of adjusting a cloth feeding direction and a cloth feeding amount by using an operation dial.

[0002]

2. Description of the Related Art Conventionally, as a sewing machine of this type, as shown in FIG. 8, a feed adjuster C capable of swinging about an axis B arranged in the left and right direction of the main body A is provided inside the sewing machine main body A. The structure provided is known.

The feed adjuster C is connected to a feed changer (not shown) and the like, and is also connected to an electromagnetic solenoid (not shown) for switching forward and reverse of the feed.
When the electromagnetic solenoid is turned off, the feed controller C is placed at the normal feed position shown by the solid line, and when turned on, it is placed at the reverse feed position shown by the chain double-dashed line. Further, a spring for constantly elastically biasing the feed adjuster C to the normal feed position acts on the feed adjuster C.

Sewing machine body A corresponding to the feed controller C
The male screw D1 of the feed adjusting screw D is the female screw A1
It is screwed to. The inner end of the feed adjusting screw D is
It is adapted to engage with the forward feed surface C1 and the reverse feed surface C2 of the feed adjuster C, and the operation dial E made of a material having relatively high rigidity such as polyacetal resin is provided at the front end of the feed adjust screw. Is fixed.

Therefore, by rotating the operation dial E to move the inner end portion of the feed adjusting screw D inward,
It is possible to reduce the cloth feed amount by changing the engagement positions for the forward and reverse feed surfaces C1 and C2 to the inside, and by changing the engagement position to the boundary portion between the both surfaces C1 and C2, the cloth feed is performed. The amount can be zero. Conversely, by moving the inner end of the feed adjusting screw D to the outside,
It is possible to increase the cloth feed amount by changing the engagement position with respect to the both surfaces C1 and C2 to the outside.

In FIG. 8, if the feed adjuster C is arranged at the position shown by the solid line, it is in the forward feed state. However, to switch from this state to the reverse feed state, the electromagnetic solenoid may be turned on. At this time, the feed adjuster C momentarily swings to the position shown by the chain double-dashed line against the elastic force of the spring, and its reverse feed surface C2 vigorously collides with the inner end of the feed adjust screw D, Held in that position. To return from this state to the normal feed state, the electromagnetic solenoid is turned off. At this time, due to the elasticity of the spring, the feed adjuster C momentarily swings from the position shown by the chain double-dashed line to the normal feed position shown by the solid line, and its normal feed surface C1 urges the inner end of the feed adjustment screw D. It collides well and is held in its position by the spring force.

[0007]

By the way, in the sewing machine having such a conventional structure, the electromagnetic solenoid is turned on and off.
Then, when the forward feed is switched to the reverse feed or the reverse feed is switched to the forward feed, the forward feed surface C1 or the reverse feed surface C2 of the feed adjuster C vigorously moves toward the inner end of the feed adjusting screw D. collide. Then, this impact is transmitted to the operation dial E via the feed adjusting screw D, but there is a problem that a large sound is generated from the operation dial E because the operation dial E is a rigid body. Further, the larger the stitch pitch, that is, the feed pitch, the louder the sound generated.

As a result of actually measuring this sound, as shown in FIG.
As shown by the solid lines in (a) and (b), it was about 75 to 85 decibels. Further, when the frequency analysis of the impact sound was examined, as shown in FIG. 4B, the peak portion of the sound pressure level was about 3300 to 3500 hertz, which was a very high-pitched sound. On the other hand, when the operation dial E is removed and the sound is measured using only the feed adjusting screw D, as shown in FIG.
As indicated by the alternate long and short dash line (b), it was quiet at about 65 to 75 decibels. Moreover, the frequency analysis of the impact sound is also shown in FIG.
As shown in (d), no large peak was observed. Then, when the natural frequency of the operation dial E was examined, it was found that the natural frequency was about 3300 to 3500 hertz, as shown in FIG. In other words, it was found that the operation dial E resonated, a speaker effect was produced, and the impact sound was increased. In this way, the operation dial E increases the sound, which gives the operator an unpleasant feeling.

The present invention has been made in order to solve the above-mentioned problems, and the impact noise generated when the feed is switched is reduced so that the operator does not feel uncomfortable. It is intended to provide a chemical structure.

[0010]

In order to achieve the above object, the invention of claim 1 is a movable feed adjuster for switching the cloth feed direction, and a feed adjuster within the moving range of the feed adjuster. A feed adjusting screw for finely adjusting the arrangement position of the feed adjusting device by engaging to determine the cloth feed amount, and an operation dial connected to the feed adjusting screw for operating the feed adjusting screw. In the sewing machine, a noise reducing structure of the sewing machine is characterized in that a member made of rubber or elastomer which is an elastic material is interposed between the operation dial and the feed adjusting screw.

According to a second aspect of the present invention, the operation dial and the feed adjusting screw are connected by a fixing screw screwed to the feed adjusting screw, and further, the inside of the operation dial and the feed adjusting screw are connected. The first member made of the elastic material is interposed in the above, and the second member made of the elastic material is interposed between the outside of the operation dial and the fixing screw. Silent structure of the described sewing machine.

According to a third aspect of the present invention, a ratchet portion that engages with an engagement pin protruding from the sewing machine body to position the operation dial is provided inside the operation dial, and the ratchet portion is made of the elastic material. The noise reduction structure of the sewing machine according to claim 1 or 2, which is formed of a hard material.

According to a fourth aspect of the present invention, the ratchet portion is a portion integrally formed at the time of molding the operation dial, and the ratchet portion and the operation dial are made of the same material harder than the elastic material. The gist of the silent structure of the sewing machine according to claim 3 is characterized in that.

According to a fifth aspect of the present invention, the movable feed adjuster for switching the cloth feed direction and the arrangement position of the feed adjuster are finely adjusted by engaging the feed adjuster within the moving range of the feed adjuster. A sewing machine provided with a feed adjusting screw for adjusting and determining the cloth feed amount, and an operation dial connected to the feed adjusting screw for operating the feed adjusting screw, wherein all or most of the operation dials are The gist is a noise-reducing structure of a sewing machine, which is composed of a material made of rubber or an elastomer which is an elastic material.

According to a sixth aspect of the present invention, a ratchet portion that engages with an engagement pin protruding from the sewing machine body to position the operation dial is provided inside the operation dial, and the ratchet portion is made of the elastic material. A gist of the noise reduction structure of the sewing machine according to claim 5 is that it is made of a hard material.

[0016]

In the invention of claim 1, the feed controller is moved to
By switching the arrangement position according to the relation with the feed adjusting screw, the cloth feeding direction can be switched between forward and reverse.
Also, operate the feed adjustment screw with the operation dial,
The amount of cloth feed is adjusted by finely adjusting the position of the feed adjuster. Then, when the cloth feeding direction is switched between forward and reverse, the feed adjuster collides with the feed adjusting screw, and the impact is transmitted to the operation dial via the feed adjusting screw. Between the adjusting screw,
Since the member made of rubber or elastomer, which is an elastic material, is interposed, the impact is alleviated / damped, the sound generated on the operation dial is reduced, and the discomfort to the operator is reduced.

According to a second aspect of the present invention, the operation dial and the feed adjusting screw are connected by a fixing screw screwed to the feed adjusting screw, and the elastic material is provided between the inside of the operation dial and the feed adjusting screw. In addition to the first member, the second member made of the elastic material is interposed between the outer side of the operation dial and the fixing screw. Therefore, both members made of the elastic material further reduce the impact. Attenuated to reduce the sound generated on the operation dial.

According to the third aspect of the invention, a ratchet portion is provided inside the operation dial for engaging the engagement pin protruding from the sewing machine body to position the operation dial, and the material of the ratchet portion is harder than the elastic material. Since it is made of a different material, the ratchet portion can be positioned reliably.

In the invention of claim 4, the ratchet portion is a portion integrally formed at the time of molding the operation dial, and the ratchet portion and the operation dial are made of the same material harder than the elastic material. The ratchet part can be formed at the same time as the operation dial is formed.
Its moldability is improved.

In the fifth aspect of the invention, the cloth feeding direction and the cloth feeding amount can be adjusted as in the first aspect. In the present invention,
Particularly, since all or most of the operation dial is made of a material made of rubber or elastomer which is an elastic material, the impact is alleviated / damped, the sound generated in the operation dial is reduced, and the operator is uncomfortable. Reduce.

According to the sixth aspect of the present invention, a ratchet portion for engaging the engagement pin protruding from the sewing machine main body to position the operation dial is provided inside the operation dial, and the material of the ratchet portion is harder than the elastic material. Since it is made of a different material, it is possible to surely perform positioning with the ratchet portion, as in the second aspect.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a cutaway view of a main part of a sewing machine having a noise reduction structure according to the present embodiment, and FIG. As shown in both figures, inside the sewing machine main body 1, there is provided a feed adjuster 3 which is swingable around a shaft 2 in the left-right direction.

A forward feed surface 3A for setting the forward feed of the cloth and a reverse feed surface 3B for setting the reverse feed of the cloth are provided at the front end portion (left side in FIG. 2) of the feed adjuster 3. Both feed surfaces 3A and 3B are formed in the inclined cam surface so as to form a V shape. In addition, the rear end of the feed adjuster 3 is connected to the upper end of a vertically long connecting rod 4, and the lower end of the connecting rod 4 is connected to a well-known switch 5. The switch 5 is well-known. It is connected to a feed dog (not shown) via a mechanism.

An electromagnetic solenoid 6 is provided on the rear side of the sewing machine body 1 corresponding to the upper and lower intermediate portions of the connecting rod 4. The plunger 6A of the electromagnetic solenoid 6 is connected to a connecting member 8 fixed to the pivot 7 via a connecting pin 6B. A coil-shaped spring 10 is stretched between the rear end of the feed adjuster 3 and the lower side of the sewing machine body 1, and the spring 10 keeps the feed adjuster 3 always clockwise in FIG. I am biased.

When the electromagnetic solenoid 6 is in the OFF state, the feed adjuster 3 is arranged at the forward feed position where the forward feed surface 3A is engaged with the rear end portion of the feed adjusting screw 11 described later, and this state is set. It is held by the spring 10. On the other hand, when the electromagnetic solenoid 6 is turned on, the plunger 6
A protrudes to the left side in FIG. 1, the connecting member 8 rotates counterclockwise, the linkage 4 moves further upward, and the feed adjuster 3
Swings in the counterclockwise direction, and the feed adjuster 3 is arranged in the reverse feed position where the reverse feed surface 3B engages with the rear end of the feed adjustment screw 11. These series of operations are instantaneously performed against the elastic force of the spring 10. Further, if the electromagnetic solenoid 6 is turned off from this state, the feed adjuster 3 is instantaneously placed at the normal feed position by the elastic action of the spring 10, and the linkage 4, the connecting member 8, the plunger 6A, etc. Instantly return to the position indicated by 1.

Sewing machine body 1 corresponding to the feed adjuster 3
In the front part of the, the male screw 1 of the metal feed adjusting screw 11
1A is screwed into the female screw 1A of the sewing machine body 1. The rear end portion 11B of the feed adjusting screw 11 is adapted to engage with the forward feed surface 3A and the reverse feed surface 3B of the feed adjuster 3.

Particularly in this embodiment, the feed adjusting screw 11 is used.
An operation dial 12 for rotating the feed adjusting screw 11 is fixed to the front end of the with a screw 13 via first and second members 14 and 15 made of rubber (or elastomer) which is an elastic member. Has been done.

The operation dial 12 is made of, for example, a plastic material which is a rigid material, and a rear recess 12B into which the first member 14 is fitted (notched in a disk shape) is provided in a rear portion of the operation dial 12, and a front portion of the operation dial 12 is provided. Is provided with a front concave portion 12C into which the second member 15 is fitted (notched in a cylindrical shape), and a hole 12D into which the screw 13 is fitted is provided in the center thereof.

Further, on the rear side portion of the operation dial 12,
A large number of groove-shaped engaging portions (ratchet portions) 12D that engage with the holding pins 16 on the sewing machine main body 1 side are arranged in a circular shape in order to hold the sewing machine main body 1 at a plurality of adjustment turning positions. A regulation projection 12A is provided to limit the rotation of the operation dial 12 within a certain range (within one rotation range) by abutting the side surface of the holding pin 16 on the side.

The outer diameter of the first member 14 is larger than the diameter of the front portion of the feed adjusting screw 11, and the screw 13 is provided at the center.
It is an annular member provided with a hole 14A for passing through.
The outer periphery of the rear side portion of the first member 14 projects along the front side outer periphery of the feed adjusting screw 11. The first member 14 is arranged between the front side portion of the feed adjusting screw 11 and the rear side portion (rear recess 12B) of the operation dial 12, and the vibration transmitted from the feed adjusting screw 11 to the operation dial 12 is transmitted. To reduce.

The outer diameter of the second member 15 is the first.
The diameter of the member 14 is smaller than that of the member 14, and the hole 15A through which the screw 13 is inserted is provided in the center. Then, it is arranged between the head of the screw 13 and the front side portion (the front concave portion 12C) of the operation dial 12 to reduce the vibration transmitted from the feed adjusting screw 11 to the operation dial 12.

The screw 13 is a step screw having different diameters in the feed adjusting screw 11, and the first and second members 1 are
The screws 4 and 15 are flexed by a predetermined amount and fixed to the feed adjusting screw 11. Next, the operation of this embodiment having the above-mentioned configuration will be described.

When the electromagnetic solenoid 6 is turned off,
When N is switched from the forward feed state to the reverse feed state, or vice versa, when switched from the ON state to the OFF state, the forward feed surface 3A or the reverse feed surface 3B of the feed adjuster 3 becomes The rear end portion 11B collides vigorously, and the impact is transmitted to the operation dial 12 via the feed adjusting screw 11. In this case, since the operation dial 12 is connected via the first and second rubber (or elastomer) members 14 and 15, the impact transmitted from the feed adjusting screw 11 is made of an elastic material. Absorbed and alleviated by
The sound generated by the operation dial 12 is reduced.

The result of actually measuring the generated sound at this time is shown in FIG.
Although shown by broken lines in (a) and (b), in this embodiment, about 68
It became quieter than the conventional example (shown by the solid line) at 77.5 dB. Further, the frequency analysis of the impact sound is shown in FIG. 4 (c), and it is understood that the resonance sound (about 3300 to 3500 hertz) of the operation dial 12 is significantly attenuated in this embodiment.

Thus, in this embodiment, the feed adjusting screw 1
1 and the operation dial 12, the first and second members 14, 1 made of rubber (or elastomer) which is an elastic material.
Since it is connected via 5, the shock transmitted from the feed adjusting screw 11 to the operation dial 12 is absorbed and alleviated, the sound generated by the operation dial 12 is reduced, and the operator is not uncomfortable. Has a great effect. (Embodiment 2) Next, the noise reduction structure of the sewing machine of Embodiment 2 will be described. This embodiment is largely different from the embodiment 1 in the configuration relating to the operation dial. The description of the same parts as those in the first embodiment will be simplified.

As shown in FIG. 5, in the sewing machine having the silent structure of this embodiment, a swingable feed adjuster 23 is provided inside the sewing machine main body 21. This feed controller 23
At the front end of the, the normal feed surface 2 for setting the normal feed of the cloth
3A and a reverse feed surface 23B for setting reverse feed of the cloth are provided, and an upper end portion of the connecting rod 24 is connected to a rear end portion of the feed adjuster 23. The lower end is connected to the switch 25.

An electromagnetic solenoid 26 is provided on the rear side of the sewing machine body 1. A plunger 26A of the electromagnetic solenoid 26 has a connecting member 28 fixed to a pivot 27.
Is connected via a connecting pin 26B. On the front side portion of the sewing machine body 21, a male screw 31A of the feed adjusting screw 31 is provided.
Is screwed into the female screw 21A of the sewing machine body 21, and the rear end portion 31B of the feed adjusting screw 31 engages with the forward feed surface 23A and the reverse feed surface 23B of the feed adjuster 23.

An operation dial 32 for rotating the feed adjusting screw 31 is fixed to the front end portion of the feed adjusting screw 31 by a screw 33. This operation dial 32
Is made of rubber (or elastomer) which is an elastic member, a rear concave portion 32B into which the front portion of the feed adjusting screw 31 is fitted is provided in the rear portion, and the head of the screw 33 is fitted into the front portion. A front concave portion 32C is provided, and a hole 32D into which the screw 33 is fitted is provided in the center thereof.

Further, on the rear side portion of the operation dial 32,
To reduce the weight, an annular recess 32E is provided outside the hole 32D. An annular ring made of hard plastic having a large number of grooves that engage with the holding pins 36 on the sewing machine main body 1 side in order to hold it at a large number of adjusting and rotating positions at a position that covers the opening of the annular concave portion 32E. The engaging portion (ratchet portion) 37 of is attached. In addition, the engaging portion 37 is provided with a restriction projection 37A that limits the rotation of the operation dial 32 within a certain range (within one rotation range) by contacting the side surface of the holding pin 36 on the sewing machine body 1 side. Has been.

The screw 33 is a step screw having a different diameter in the feed adjusting screw 31, and the operation dial 32 is bent by a predetermined amount and fixed to the feed adjusting screw 31.
Next, the operation of this embodiment having the above-mentioned configuration will be described. Similar to the first embodiment, the electromagnetic solenoid 26 is set to OF
When the F state is turned ON to switch from the forward feed state to the reverse feed state, and vice versa, from the ON state to the OFF state,
Forward feed surface 23A or reverse feed surface 23B of feed adjuster 23
But violently collides with the rear end portion 31B of the feed adjusting screw 31, and the impact is transmitted to the operation dial 32 via the feed adjusting screw 31. In this case, since the operation dial 32 is made of rubber (or elastomer), the shock transmitted from the feed adjusting screw 31 is absorbed and alleviated, and the sound generated by the operation dial 32 is reduced.

FIG. 6 shows the result of actually measuring the generated sound at this time.
Although indicated by broken lines in (a) and (b), in this embodiment, about 67
It became quieter than the conventional example (shown by the solid line) at ~ 77 dB. Further, the frequency analysis of the impact sound is shown in FIG. 7B, but in this embodiment, the resonance sound (about 3300 to 3500 hertz) of the conventional operation dial shown in FIG. 7A does not appear. I understand.

Thus, in this embodiment, the operation dial 3
2. Rubber (or elastomer) that is an elastic material
Since it is composed of, the shock transmitted from the feed adjusting screw 31 is largely absorbed and mitigated, the sound generated by the operation dial 32 is reduced, and the remarkable effect that the operator is not uncomfortable.

Particularly, in this embodiment, since the engaging portion 37 is made of hard plastic, there is an advantage that the positioning can be performed more reliably, and there is an effect that it is more durable and durable. Needless to say, the present invention is not limited to the above-mentioned embodiments, and can be carried out in various modes without departing from the scope of the present invention.

[0044]

As is clear from the above description,
According to the first aspect of the present invention, since a member made of rubber or elastomer, which is an elastic material, is interposed between the operation dial and the feed adjusting screw, when the feed adjuster is moved to switch between forward and reverse feed. The shock transmitted from the feed adjustment screw to the operation dial can be reduced or dampened. As a result, the sound generated by the operation dial can be reduced, so that discomfort to the operator can be reduced.

According to the second aspect of the present invention, the first member made of an elastic material is interposed between the inside of the operation dial and the feed adjusting screw, and the outside member of the operation dial is made of the elastic material. Since the second member is interposed, the shock is further alleviated / damped, and the sound generated on the operation dial is reduced.

According to the third aspect of the present invention, since the material of the ratchet portion is made of a material harder than the elastic material, the ratchet portion can surely perform positioning. In the invention of claim 4, the ratchet portion is a portion integrally formed at the time of molding the operation dial, and since the ratchet portion and the operation dial are formed of the same material harder than the elastic material, the molding thereof is performed. There is an advantage that the property is improved.

In the invention of claim 5, since all or most of the operation dial is made of a material made of elastic material such as rubber or elastomer, the impact is alleviated / damped as in the case of claim 1. The sound generated on the operation dial is reduced, and discomfort to the operator can be reduced.

In the invention of claim 6, since the material of the ratchet portion is made of a material harder than the elastic material,
Similar to the second aspect, the ratchet portion can surely perform the positioning.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of a sewing machine according to a first embodiment.

FIG. 2 is an external perspective view of a sewing machine.

FIG. 3 is a graph showing a sound level when an electromagnetic solenoid is turned on and off.

FIG. 4 is a diagram showing frequency analysis of impact sound.

FIG. 5 is a cross-sectional view of essential parts of a sewing machine according to a second embodiment.

FIG. 6 is a graph showing sound levels when an electromagnetic solenoid is turned on and off.

FIG. 7 is a diagram showing frequency analysis of impact sound.

FIG. 8 is an enlarged cross-sectional view of a conventional operation dial portion.

[Explanation of symbols]

 1, 21 ... Sewing machine main body 3, 23 ... Feed adjuster 11, 31 ... Feed adjusting screw 12, 32 ... Operation dial 12D, 37 ... Engaging portion 13, 33 ... Screw

Claims (6)

[Claims] 1. A movable feed adjuster for switching a cloth feed direction, and finely adjusting a disposition position of the feed adjuster by engaging the feed adjuster within a moving range of the feed adjuster. A sewing machine comprising a feed adjusting screw for determining a quantity and an operation dial connected to the feed adjusting screw for operating the feed adjusting screw, wherein an elastic member is provided between the operation dial and the feed adjusting screw. A noise reduction structure for a sewing machine, in which a member made of rubber or elastomer as a material is interposed. 2. The operation dial and the feed adjusting screw are connected by a fixing screw screwed to the feed adjusting screw, and the elastic material is formed between the inside of the operation dial and the feed adjusting screw. The silent member of the sewing machine according to claim 1, wherein a second member made of the elastic material is interposed between the outer side of the operation dial and the fixing screw while the first member is interposed. Structure. 3. A ratchet portion is provided inside the operation dial for engaging with an engagement pin protruding from the sewing machine main body to position the operation dial, and the ratchet portion is made of a material harder than the elastic material. The noise reduction structure for a sewing machine according to claim 1 or 2, wherein 4. The ratchet portion is a portion integrally formed when the operation dial is molded, and the ratchet portion and the operation dial are made of the same material that is harder than the elastic material. The silent structure of the sewing machine according to claim 3. 5. A movable feed adjuster for switching the cloth feed direction, and finely adjusting the arrangement position of the feed adjuster by engaging with the feed adjuster within the moving range of the feed adjuster to feed the cloth. A sewing machine having a feed adjusting screw for determining a quantity and an operation dial connected to the feed adjusting screw for operating the feed adjusting screw, wherein all or most of the operation dial is made of an elastic material. A noise-reducing structure for a sewing machine characterized by being made of a material made of rubber or elastomer. 6. A ratchet portion is provided inside the operation dial to engage an engagement pin protruding from the sewing machine main body to position the operation dial, and the ratchet portion is made of a material harder than the elastic material. The noise reduction structure of the sewing machine according to claim 5, wherein