JP2007175151A - Bearing structure of sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To keep the excellent quality of grease housed in the grease housing part of a bearing member for supporting a rotary shaft so as to be rotated and supporting a slide shaft so as to be moved back and forth, and to maintain a lubricating performance by the grease for a long period of time. <P>SOLUTION: In the first bearing structure 15 of an electronic sewing machine 1 comprising a first bearing member 16 for supporting a main shaft 6 so as to be rotated around an axial center and the grease housing part 16a formed on it, dust trap grooves 6a are respectively formed at both parts more on the outer side in an axial center direction than the first bearing member 16 of the main shaft 6, the grease G which is a lubricant is applied to the respective dust trap grooves 6a, and cap members 17L and 17R are respectively provided on both ends of the first bearing member 16 so as to closely cover at least the outer peripheral side of the dust trap grooves 6a. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rotating shaft that rotates about an axis or a sliding shaft that reciprocally moves in an axial direction and is supported by a bearing member using a lubricant such as grease.

  Conventionally, in general, in a mechanical drive system, when a rotating shaft that rotates around an axis or a sliding shaft that reciprocates is supported by a bearing member so as to be able to rotate and slide, the rotating shaft and the sliding shaft rotate smoothly. In order to allow sliding, a lubricant such as grease is used between the rotating shaft or the sliding shaft and the bearing member to prevent the rotating shaft and the sliding shaft from being seized. In particular, in industrial sewing machines and household sewing machines, a lubricant used for a bearing sliding surface that supports a spindle that rotates at a high speed or a needle bar that moves up and down at a high speed so as to promote dryness. As the grease is adopted.

For example, the sliding device for a sewing machine disclosed in Patent Document 1 has an annular groove having a minute depth at a predetermined interval in a portion that becomes a sliding surface supported by a needle bar bearing on an outer peripheral surface of a needle bar that moves up and down. Are formed in the axial direction, and each annular groove is filled with grease. On the other hand, a wide annular grease retaining portion that opens to the inner peripheral surface is formed inside the substantially cylindrical needle bar bearing, and the grease retaining portion is also filled with grease. Thus, since the grease can be held by both the plurality of annular grooves provided in the needle bar and the grease holding part of the needle bar bearing, damage due to wear and seizure of the sliding portion is prevented.
Japanese Patent Laid-Open No. 2002-45587 (pages 3 to 4, FIG. 2)

  In the sewing machine sliding device described in Patent Document 1, since the grease holding portions of the needle bar bearing and the plurality of annular grooves provided in the needle bar are also filled with grease, The lubricant is formed in a thin film. On the other hand, in a sewing factory, when sewing operations are performed all at once by a plurality of sewing machines installed in the factory, fine yarn waste generated from fabrics and sewing threads and fiber-based dust separated from the fabrics are generated. It is often contained in large amounts in the air.

  Therefore, fine fiber dust contained in the air in the factory comes to adhere to the surface of the needle bar of the sewing machine through a thin film lubricant. In this way, the fiber-based dust adhering to the surface of the needle bar is accumulated by entering the grease holding section and the annular groove through a minute gap between the needle bar and the needle bar bearing by the vertical movement of the needle bar. Become. As a result, if the amount of accumulated fiber dust in these grease retaining parts and annular grooves increases, not only the amount of grease retained, but also the grease quality deteriorates and the lubricity of the grease decreases, resulting in burning. There is a problem that sticking occurs.

  An object of the present invention is to maintain the quality of the grease accommodated in the grease accommodating portion of the bearing member and to maintain the lubrication performance by the grease for a long period of time.

  The bearing structure for a sewing machine according to claim 1 is a bearing structure for a sewing machine having a bearing member that rotatably supports a rotating shaft about an axis and a grease accommodating portion formed on the bearing member. An annular dust trap groove formed on the outer side in the center direction and coated with a lubricant, and a cap fixedly provided at the end of the bearing member so as to cover at least the outer peripheral side of the dust trap groove in a close proximity And a member.

  The rotating shaft is rotatably supported by the bearing member via a lubricant filled in a grease accommodating portion formed in the bearing member. A dust trap groove is formed on the rotating shaft, lubricant is applied to the dust trap groove, and the outer periphery of the dust trap groove is covered with a cap member so that the fiber-based dust contained in the air The cap member does not obstruct the grease containing portion directly.

  Even if fiber dust contained in the air enters the narrow shaft gap between the cap member and the rotating shaft, most of the dust and dust is applied to the dust trap groove in front of the grease container. Adheres to highly viscous lubricants. Therefore, dust does not accumulate in the lubricant in the grease container, and the lubricating performance of the lubricant housed in the grease container is maintained.

  According to a bearing structure of a sewing machine according to a second aspect of the present invention, in the first aspect of the invention, the cap member enters the dust trap groove and guides dust that has entered from the gap between the cap member and the rotating shaft to the dust trap groove. It has an annular protrusion.

  A bearing structure for a sewing machine according to a third aspect of the present invention is the bearing structure according to the second aspect, wherein a dust trap groove and a cap member are provided on both ends of the bearing member.

  A bearing structure for a sewing machine according to claim 4, wherein the bearing structure for the sewing machine has a bearing member for supporting the sliding shaft so as to be capable of reciprocating in the axial direction and a grease accommodating portion formed on the bearing member. An annular dust trap groove formed on the outer side in the axial direction and coated with a lubricant, and a width dimension larger than the axial movement distance of the dust trap groove, and the outer periphery of the dust trap groove And a cap member fixedly provided at the end of the bearing member so as to cover the side in a close proximity.

  The sliding shaft is supported by the bearing member so as to be able to reciprocate through a lubricant filled in a grease accommodating portion formed in the bearing member. A dust trap groove is formed on the sliding shaft, lubricant is applied to the dust trap groove, and the outer peripheral side of the dust trap groove is closely covered with a cap member, so that the fiber-based dust contained in the air Is not obstructed by the cap member and does not directly enter the grease accommodating portion.

  Even if fiber dust contained in the air enters the shaft gap between the cap member and the sliding shaft, most of the dust and dust is applied to the dust trap groove in front of the grease container. Adheres to highly viscous lubricants. Therefore, dust does not accumulate in the lubricant in the grease container, and the lubricating performance of the lubricant housed in the grease container is maintained.

  According to a fifth aspect of the bearing structure of the sewing machine of the present invention, in the invention of the fourth aspect, the dust trap groove is formed to have a width that is larger than the movement distance in the axial direction of the sliding shaft, and the cap member enters the dust trap groove. In addition, it has an annular protrusion that moves the dust that has entered the dust trap groove from the gap between the cap member and the sliding shaft in a direction away from the bearing member.

  A bearing structure for a sewing machine according to a sixth aspect of the present invention is the invention according to the first or fourth aspect, wherein the dust trapping groove is composed of a plurality of annular grooves formed in a spaced manner in the axial direction.

  According to the first aspect of the present invention, in the bearing structure of the sewing machine having the bearing member that rotatably supports the rotating shaft around the axis and the grease receiving portion formed on the bearing member, the dust trap groove is formed on the rotating shaft. Further, since the lubricant is applied to the dust trap groove, and the cap member that covers at least the outer peripheral side of the dust trap groove close to the end of the bearing member is provided, the fiber dust contained in the air is capped. Even when it enters the shaft clearance between the member and the rotating shaft, it adheres to the highly viscous lubricant applied to the dust trap groove in front of the grease accommodating portion and hardly adheres to the grease accommodating portion. . Therefore, the deterioration of the quality of the lubricant accommodated in the grease accommodating portion can be reliably suppressed, and the lubricity of the lubricant accommodated in the grease accommodating portion can be maintained for a long time.

  According to the invention of claim 2, the cap member has the annular protrusion that enters the dust trap groove and guides the dust that has entered from the gap between the cap member and the rotating shaft to the dust trap groove. The dust that has entered from the shaft gap between the member and the rotating shaft is reliably guided to the dust trap groove by the annular protrusion, and the dust can be effectively and reliably taken up by the dust trap groove. Other effects similar to those of the first aspect are obtained.

  According to the third aspect of the present invention, since the dust trap groove and the cap member are provided at both ends of the bearing member, it is possible to reliably take in dust from any of the left and right sides of the bearing member. Therefore, it is possible to more reliably suppress deterioration in the quality of the lubricant stored in the grease storage portion. Other effects similar to those of the second aspect are achieved.

  According to the invention of claim 4, in the bearing structure of the sewing machine having the bearing member that supports the sliding shaft so as to be reciprocally movable in the axial direction and the grease accommodating portion formed in the bearing member, And an annular dust trap groove formed on the outer side in the axial direction and coated with a lubricant, and having a width dimension larger than the movement distance of the dust trap groove in the axial direction, and on the outer peripheral side of the dust trap groove. And a cap member fixedly provided at the end of the bearing member so as to cover them closely, so that fiber dust contained in the air enters the shaft gap between the cap member and the sliding shaft. Even in this case, it adheres to the highly viscous lubricant applied to the dust trap groove before the grease accommodating portion and hardly adheres to the grease accommodating portion. Therefore, the deterioration of the quality of the lubricant accommodated in the grease accommodating portion can be reliably suppressed, and the lubricating performance of the lubricant accommodated in the grease accommodating portion can be maintained for a long time.

  According to a fifth aspect of the present invention, the dust trap groove is formed to have a width that is greater than the moving distance of the sliding shaft in the axial direction, the cap member protrudes into the dust trap groove, and the cap member, the sliding shaft, Since there is an annular protrusion that moves dust that has entered the dust trap groove from the shaft clearance between the cap member and the sliding shaft, dust enters the dust trap groove. Even if it adheres to the lubricant applied to the dust, the dust that adheres to the lubricant in the dust trap groove is pushed away from the bearing member by the annular projection, that is, pushed back to the outside, so that dust does not accumulate in the grease storage part. Can be suppressed. Other effects similar to those of the fourth aspect are achieved.

  According to the invention of claim 6, since the dust trap groove is composed of a plurality of annular grooves formed in the axial direction so as to be separated from each other, dust entering the shaft gap between the rotating shaft and the cap member is removed. The labyrinth-seal-like sealing function can be taken in more effectively. Other effects similar to those of the first or fourth aspect are achieved.

  The bearing structure of the sewing machine according to the present embodiment is formed with an annular dust trap groove for accommodating a lubricant outside the grease accommodating portion of the rotating shaft or sliding shaft, and the dust trap groove is covered with a cap member to Fine fiber-based dust and dust contained therein are preempted by a dust trap groove to prevent entry of dust and dust into the grease accommodating portion.

  As shown in FIG. 1, the electronic sewing machine 1 includes a bed portion 2 having a thread catcher such as a rotary hook, a leg column portion 3 erected on the right end portion of the bed portion 2, and a leg column portion 3. The arm portion 4 extends leftward from the upper end. Although not shown, the bed portion 2 is provided with a rotary hook driven by a hook shaft (lower shaft) that rotates in synchronization with the main shaft 6 (see FIG. 2).

  The arm portion 4 is provided with a main shaft 6 (which corresponds to a rotating shaft) in the left-right direction, and the main shaft 6 can be rotated around an axis by a first bearing member 16 of a first bearing structure 15 described later. It is supported. The head 5 of the arm 4 is provided with a needle bar vertical movement mechanism 9 that is connected to the left end of the main shaft 6 and drives the needle bar 7 (which corresponds to a sliding shaft) up and down.

  The needle bar 7 is supported at the upper part by a bearing member (bearing metal) 13 fixed to the machine frame F so as to be movable up and down, and at the lower part by a second bearing member 21 of a second bearing structure 20 described later. Has been. A sewing needle 8 is attached to the lower end portion of the needle bar 7, and a needle bar holder 10 is fixed to the middle step in the height direction of the needle bar 7.

  On the other hand, a needle bar crank (balance weight) 11 having a connecting pin 11a is fixed to the left end portion of the main shaft 6, and the upper end portion of the needle bar crank rod 12 is rotatably supported by the connecting pin 11a. A lower end portion of the needle bar crank rod 12 is connected to the needle bar 7 via a needle bar holder 10.

First, the first bearing structure 15 that rotatably supports the main shaft 6 will be described.
As shown in FIGS. 2 and 3, the main shaft 6 disposed horizontally in the arm portion 4 is rotated around the axis by a first bearing member (bearing metal) 16 disposed in a penetrating manner in the machine frame F. Supported as possible. The first bearing member 16 has an annular grease accommodating portion (which corresponds to a lubricant accommodating portion) 16 a having a predetermined width dimension (for example, about 5 to 10 mm) at a substantially central portion in the left-right direction. The sliding surface D is formed so as to open.

  A pair of left and right annular dust trap grooves 6a are formed in a portion of the main shaft 6 just outside the first bearing member 16 in the axial direction. Cylindrical cap members 17L and 17R are fixed to the left and right ends of the first bearing member 16 by a plurality of fixing bolts 18 in close contact with each other. That is, as shown in FIG. 3, each cap member 17L, 17R is made of synthetic resin and has a width dimension (width dimension in the left-right direction) that covers the entire corresponding dust trap groove 6a.

  Here, the horizontal width dimension of each dust trap groove 6a is about 5 mm corresponding to 1/3 of the diameter (about 15 mm) of the main shaft 6, and the depth of each dust trap groove 6a is about 1 mm. Further, the sliding surface gap between the outer peripheral surface of the main shaft 6 and the inner peripheral surface of the first bearing member 16 is about 0.02 mm, which is very small. However, the shaft gap g1 between the inner peripheral surfaces of the cap members 17L and 17R and the outer peripheral surface of the main shaft 6 is set large, for example, to about 0.3 to 0.5 mm so that the cap members 17L and 17R do not contact the main shaft 6. Yes.

  However, as shown in FIG. 3 in the inner peripheral surfaces of the cap members 17L and 17R, the portion corresponding to the dust trap groove 6a has an annular protrusion 17La that protrudes into the dust trap groove 6a with a substantially triangular cross section. , 17Ra are formed. That is, each annular protrusion 17La, 17Ra has inclined surfaces 17Lb, 17Rb on the outer surface in the axial direction. By the inclined surfaces 17Lb and 17Rb, dust H entering from the outside through the shaft gap g1 between the cap members 17L and 17R and the main shaft 6 is guided to the dust trap grooves 6a and 6b. Therefore, the grease containing portion 16a is filled with grease G as a lubricant, and an appropriate amount of grease G is applied to the dust trap groove 6a.

  That is, since the outer peripheral side of the dust trap groove 6a is always covered closely by the cap members 17L and 17R, even when the main shaft 6 rotates at high speed, the grease G in the dust trap groove 6a is prevented from scattering to the outside. Even when dust H in the air enters the shaft gap g1 between the cap members 17L, 17R and the main shaft 6, the annular protrusions 17La, 17Ra cannot enter the grease accommodating portion 16a.

  However, each of the cap members 17L, 17R provided on the left and right sides of the first bearing member 16 is divided in parallel with the axis of the main shaft 6, that is, in the horizontal direction, and the annular protrusions 17La, 17Ra are separated from the dust. The cap members 17L and 17R which are divided in half while being inserted into the trap groove 6a are integrally assembled and fixed to the first bearing member 16 with a fixing screw 18.

  Incidentally, the lower part of the needle bar 7 is supported by the second bearing member 21 of the second bearing structure 20 so as to be reciprocally movable in the vertical direction (axial direction). Then, next, this 2nd bearing structure 20 is demonstrated.

  The needle bar 7 is supported by a lower second bearing member (bearing metal) 21 disposed in a penetrating manner in the machine frame F so as to be reciprocally movable in the vertical direction. As shown in FIG. 4, similar to the first bearing member 16, the second bearing member 21 has an annular grease accommodating portion 21a having a predetermined width dimension (for example, about 5 mm) in the middle portion in the vertical direction. (Corresponding to a lubricant accommodating portion) is formed so as to open on a sliding surface E with the main shaft 6.

  A pair of upper and lower annular dust trap grooves 7a are formed on both upper and lower sides of the needle bar 7 in the axial direction relative to the second bearing member 21. Cylindrical cap members 22U and 22D are screwed in close contact with a plurality of fixing bolts 23 at both upper and lower ends of the second bearing member 21, respectively. That is, as shown in FIG. 4, each cap member 22U, 22D is made of synthetic resin and has a width dimension (vertical width dimension) covering the entire dust trap groove 7a. However, the length L of each cap member 22U, 22D is larger than the vertical movement stroke S of the needle bar 7.

  Here, the width dimension (height dimension) of each dust trap groove 7a is about 40 mm corresponding to the vertical movement stroke S of the needle bar 7, and the depth is about 1 mm. Further, the sliding surface gap between the outer peripheral surface of the needle bar 7 and the inner peripheral surface of the second bearing member 21 is about 0.02 mm, which is very small. However, the shaft gap g2 between the inner peripheral surface of the cap members 22U and 22D and the outer peripheral surface of the needle bar 7 is set to be large, for example, 0.3 to 0.5 mm so that the cap members 22U and 22D do not contact the main shaft 6. Yes.

  However, as shown in FIG. 4 in the inner peripheral surface of each cap member 22U, 22D, the portion corresponding to the dust trap groove 7a has an annular protrusion 22Ua that protrudes into the dust trap groove 7a with a substantially crescent-shaped cross section. , 22 Da are formed. In other words, each of the annular protrusions 22Ua and 22Da is formed in a substantially crescent-shaped cross section that faces outward in the axial direction.

  The direction in which the dust H adhering from the outside through the shaft gap g2 between the cap members 22U and 22D and the needle bar 7 and adhering to the dust trap groove 7a is moved away from the second bearing member 21 by the annular protrusions 22Ua and 22Da. To move to. Therefore, the grease containing portion 21a is filled with grease G as a lubricant, and an appropriate amount of grease G is applied to the dust trap groove 7a.

  That is, since the outer peripheral side of the dust trap groove 7a is covered in proximity by the cap members 22U and 22D, the grease G in the dust trap groove 7a does not scatter to the outside even when the needle bar 7 reciprocates up and down at high speed. In addition, even when dust H in the air enters the shaft gap g2 between the cap members 22U, 22D and the needle bar 7, the annular protrusions 22Ua, 22Da cannot enter the grease accommodating portion 21a. Yes.

  However, each of the cap members 22U and 22D provided on the upper and lower sides of the second bearing member 21 is divided in parallel with the axis of the needle bar 7, that is, in the vertical direction, and the annular protrusions 22Ua and 22Da are divided. The cap members 22U and 22D which are divided in half while entering the dust trapping grooves 7a are integrally assembled and fixed to the second bearing member 21 with fixing screws 23.

Next, the operation and effect of the first bearing structure 15 configured as described above will be described.
When the operator periodically performs maintenance and inspection of the electronic sewing machine 1, the grease storage portions 16 a are filled with the grease G, and the cap members 17 </ b> L and 17 </ b> R are removed from the first bearing member 16, and each dust trap groove After performing a cleaning operation to remove the dust H accumulated in 6a, a new appropriate amount of grease G is applied.

  When a plurality of electronic sewing machines 1 including the electronic sewing machine 1 are installed in a sewing factory and the plurality of electronic sewing machines 1 perform a sewing operation at the same time, a minute amount generated from a cloth or sewing thread used for sewing is used. Dust H such as fiber cloth separated from yarn waste or fabric floats using air as a medium, and fills the arm 4 through an opening or the like provided at the lower end of the head 5. .

  Therefore, as shown in FIG. 3, since the main shaft 6 is rotated at a high speed, the fiber dust H filled in the arm portion 4 passes through the shaft gap g1 between the cap members 17L, 17R and the main shaft 6. An attempt is made to enter the first bearing member 16. However, the dust H entering the shaft gap g1 and moving toward the first bearing member 16 is guided to the dust trap groove 6a by the annular protrusions 17La and 17Ra of the cap members 17L and 17R.

  In this case, since the grease G applied to each dust trap groove 6a has a specific viscosity, the dust H that has entered the shaft gap g1 is guided to each dust trap groove 6a, and most of the dust H is dust trap groove 6a. It adheres effectively to the grease G applied to the surface. That is, most of the fiber dust H that has entered the shaft gap g1 is preempted by the dust trap grooves 6a. As a result, the dust H passing through the sliding surface D between the main shaft 6 and the first bearing member 16 is drastically reduced, and the dust H hardly enters and accumulates in the grease accommodating portion 16a.

  However, when the electronic sewing machine 1 is used over a long period of time, some dust H accumulates in each dust trap groove 6a of the main shaft 6. Therefore, during regular maintenance work, the operator loosens the fixing bolt 18 and removes the cap members 17L and 17R, and removes the dust H and old grease G accumulated in the dust trap grooves 6a. Apply grease G.

  As described above, in the first bearing structure 15 of the electronic sewing machine 1 having the first bearing member 16 that supports the main shaft 6 so as to be rotatable around the shaft center and the grease accommodating portion 16a formed on the first bearing member 16, the grease accommodation of the main shaft 6 is performed. The dust trap grooves 6a to which the grease G is applied are formed on both outer sides in the axial direction from the portion 16a, and the grease G is applied to each dust trap groove 6a.

  Moreover, since the cap members 17L and 17R that cover at least the outer peripheral side of the dust trap groove 6a in proximity are provided at both ends of the first bearing member 16, respectively, the fiber dust H contained in the air is trapped in the cap member 17L. , 17R and the main shaft 6, even when it enters the shaft gap g1, it adheres to the highly viscous grease G applied to the dust trap groove 6a in front of the grease storage portion 16a, and almost remains in the grease storage portion 16a. It will not stick.

  Therefore, quality degradation of the grease G stored in the grease storage portion 16a can be reliably suppressed, and the lubricity of the grease G stored in the grease storage portion 16a can be maintained for a long time.

  Further, since the dust trap groove 6a is formed to have a groove width that is at least 1/3 of the diameter of the main shaft 6, the peripheral speed of the main shaft 6 increases as the diameter of the main shaft 6 increases, and a lot of fiber dust. Even if H easily enters a large amount in the shaft gap g1 between the main shaft 6 and the cap members 17L and 17R, the dust H can be efficiently taken in by the wide dust trap groove 6a.

  Each cap member 17L, 17R protrudes into the dust trap groove 6a, and the annular protrusion 17Lb guides the dust H that has entered from the shaft gap g1 between the cap members 17L, 17R and the main shaft 6 to the dust trap groove 6a. , 17Rb, the dust H entering from the shaft gap g1 between the cap members 17L, 17R and the main shaft 6 is reliably guided to the dust trap groove 6a by the annular protrusions 17Lb, 17Rb, and the dust H is trapped in the dust trap. The groove 6a can be taken in effectively and reliably.

Next, the operation and effect of the second bearing structure 20 will be described.
When the operator periodically conducts maintenance and inspection of the electronic sewing machine 1, as described above, the fixing bolt 23 is loosened to remove the dust H accumulated in each dust trap groove 7a, and a new appropriate amount of grease G is removed. Apply.

  As described above, since dust H such as fiber-based cloth is floating in the sewing factory using air as a medium, the needle bar 7 reciprocates up and down at high speed as shown in FIG. Then, the fiber-based dust H filled in the arm portion 4 tends to enter the second bearing member 21 through the shaft gap g2 between the cap members 22U and 22D and the needle bar 7.

  However, the dust H entering the shaft gap g2 and moving toward the second bearing member 21 becomes obstructed by the crescent-shaped annular protrusions 22Ua and 22Da and is confined in the wide dust trap groove 7a. It is done.

  In this case, since the grease G applied to each dust trap groove 7a has a specific viscosity, most of the dust H that has entered the shaft gap g2 is effectively applied to the grease G applied to the dust trap groove 7a. Adhere to. That is, most of the fiber dust H that has entered the shaft gap g2 is preempted by the dust trap grooves 7a. As a result, the dust H that passes through the sliding surface E between the needle bar 7 and the second bearing member 21 is drastically reduced, and the dust H hardly enters and accumulates in the grease accommodating portion 21a.

  However, when the electronic sewing machine 1 is used over a long period of time, some dust H accumulates in each dust trap groove 7a of the needle bar 7. Therefore, during regular maintenance work, the operator loosens the fixing bolt 23, removes the cap members 22U and 22D, removes the dust H and the old grease G accumulated in the dust trap grooves 7a, and cleans them manually. Apply grease G.

  As described above, in the second bearing structure 20 of the electronic sewing machine 1 having the second bearing member 21 that supports the needle bar 7 so as to be reciprocally movable in the vertical direction (axial direction) and the grease accommodating portion 21a formed thereon. In addition, dust trap grooves 7a coated with grease G are formed on both outer sides of the needle bar 7 in the axial direction from the grease accommodating portion 21a, and the dust trap grooves 7a are formed at both ends of the second bearing member 21, respectively. Since the cap members 22U and 22D that cover at least the outer peripheral side are provided respectively, the fiber dust H contained in the air enters the shaft gap g2 between the cap members 22U and 22D and the needle bar 7. However, it adheres to the highly viscous grease G applied to the dust trap groove 7a before the grease accommodating portion 21a, and hardly adheres to the grease accommodating portion 21a.

  Therefore, quality degradation of the grease G accommodated in the grease accommodating portion 21a can be reliably suppressed, and the lubricating performance of the grease G accommodated in the grease accommodating portion 21a can be maintained for a long time.

  Each dust trap groove 7a is formed to have a width L larger than the movement distance S of the needle bar 7 in the axial direction, and the cap members 22U and 22D enter the dust trap groove 7a and the cap members 22U and 22D. Since there are annular protrusions 22Ua and 22Da that move the dust H that has entered the dust trap groove 7a from the shaft gap g2 between the needle bar 7 and away from the second bearing member 21, the cap members 22U and 22D and the needle bar Even if the grease penetrates from the shaft gap g2 with the grease 7 and adheres to the grease G applied to the dust trap groove 7a, the dust H adhering to the grease G in the dust trap groove 7a is removed by the annular protrusions 22Ua and 22Da. It is possible to prevent dust H from being accumulated in the grease accommodating portion 21a by being pushed back in the direction away from the bearing member 21, that is, to the outside.

Next, a modified form of the embodiment will be described.
1) The first modification will be described. The first bearing structure 15A may be configured by a plurality of annular grooves 6b to 6d having a small groove width formed as spaced apart as the dust trap grooves 6a formed on the main shaft 6A. However, members similar to those in the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted.

  That is, as shown in FIG. 5, the dust trap grooves 6a formed respectively on the left and right sides of the main shaft 6A are composed of three first to third annular grooves 6b to 6d formed sequentially on the main shaft 6A. . However, the cap members 17LA and 17RA are not provided with an annular protrusion.

  Therefore, the labyrinth seal function can be exhibited by the plurality of annular grooves 6b to 6d. However, the groove widths of these three annular grooves 6b to 6d are: first annular groove 6b <second annular groove 6c <third annular groove 6d, and each annular groove 6b to 6d is filled with grease G.

  In this case, the fiber dust H that has entered the shaft gap g1 first adheres to the wide third annular groove 6d that is farthest from the first bearing member 16, that is, outside, and this third annular groove 6d. The remaining dust H that could not be removed in this step is adhered to the grease G in the next second annular groove 6c, and further, the remaining dust H that could not be removed in the second annular groove 6c is the next first annular groove. It adheres to the grease G of 6b.

  Therefore, these three first to third annular grooves 6b to 6d can reliably remove almost 95% of the fiber dust H that has entered the shaft gap g1, and the dust accumulated in the grease accommodating portion 16a. H is almost gone.

2) The second modification will be described. The second bearing structure 20A may be configured as a plurality of annular grooves 7b to 7d having a small groove width formed as spaced apart as each dust trap groove 7a formed in the needle bar 7A. However, members similar to those in the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. The cap members 22UA and 22DA are not provided with an annular protrusion.

  That is, as shown in FIG. 6, each of the pair of upper and lower dust trap grooves 7a formed on the needle bar 7A has three first to third annular grooves 7b to 7d sequentially formed on the second bearing member 21. It is made up of. However, the cap members 22UA and 22DA are not provided with an annular protrusion.

  Therefore, the labyrinth seal function can be exhibited by the plurality of annular grooves 7b to 7d. However, the groove widths of these three annular grooves 7b to 7d are first annular groove 7b <second annular groove 7c <third annular groove 7d, and grease G is filled in each annular groove 7b to 7d. Further, the length L of each cap member 22UA, 22DA is longer than the vertical movement stroke S of the needle bar 7.

  In this case, the dust H that has entered the shaft gap g2 first adheres to the grease G of the wide third annular groove 7d that is farthest from the second bearing member 21, that is, located outside, and this third annular groove 7d. The remaining dust H that could not be removed in this step is adhered to the grease G in the next second annular groove 7c, and further, the remaining dust H that could not be removed in the second annular groove 7c is the next first annular groove. It adheres to the grease G of 7b.

  Therefore, these three first to third annular grooves 7b to 7d can reliably remove almost 95% of the fiber-based dust and dust H that has entered the shaft gap g2, and accumulate in the grease accommodating portion 21a. Dust H is almost gone.

3) In the first bearing structure 15 described above, the annular protrusions 17La and 17Ra of the cap members 17L and 17R may be omitted. Even in this case, the same effect as the above-described embodiment can be obtained.

4) The first bearing structure 15 described above may be configured such that the grease accommodating portion is provided at an intermediate portion between the pair of dust trap grooves 6 a provided on the main shaft 6.

5) In the second bearing structure 20 described above, the annular protrusions 22Ua and 22Da of the cap members 17U and 17D may be omitted. Even in this case, the same effect as the above-described embodiment can be obtained.

6) The above-described second bearing structure 20 may be configured such that the grease accommodating portion is provided at an intermediate portion between the pair of dust trap grooves 7a included in the needle bar 7.

7) The present invention is not limited to the embodiments described above, and those skilled in the art can implement the present invention by adding various modifications without departing from the spirit of the present invention. The present invention includes those modifications.

It is a front view of the electronic sewing machine which concerns on the Example of this invention. It is a partial enlarged front view which shows the internal structure of a head. It is a principal part longitudinal section front view showing the 1st bearing structure. It is a principal part vertical front view which shows a 2nd bearing structure. FIG. 4 is a diagram corresponding to FIG. 3 according to a first modification. FIG. 5 is a diagram corresponding to FIG. 4 according to a second modification.

Explanation of symbols

1 Electronic sewing machine 6 Main shaft 6a Dust trap groove 6b Annular groove 6c Annular groove 6d Annular groove 7 Needle bar 7a Dust trap groove 7b Annular groove 7c Annular groove 7d Annular groove 15 First bearing structure 16 First bearing member 16a Grease accommodating part 20 Two-bearing structure 21 Second bearing member 21a Grease accommodating portion 17L Cap member 17La Annular projection 17R Cap member 17Ra Annular projection 22U Cap member 22Ua Annular projection 22D Cap member 22Da Annular projection G Grease H Dust

Claims (6)

In a bearing structure of a sewing machine having a bearing member that rotatably supports a rotating shaft around an axis, and a grease accommodating portion formed on the bearing member,
An annular dust trap groove formed on a portion of the rotating shaft outside the bearing member in the axial direction and coated with a lubricant;
A cap member fixedly provided at an end of the bearing member so as to cover at least the outer peripheral side of the dust trap groove in a close proximity;
Sewing machine bearing structure characterized by comprising   The said cap member has the annular protrusion which guides the dust which penetrated into the said dust trap groove | channel, and entered from the clearance gap between a cap member and a rotating shaft to a dust trap groove | channel. Sewing machine bearing structure.   The bearing structure for a sewing machine according to claim 2, wherein a dust trap groove and a cap member are provided on both ends of the bearing member. In a bearing structure of a sewing machine having a bearing member that supports a sliding shaft so as to be capable of reciprocating in the axial direction and a grease accommodating portion formed on the bearing member,
An annular dust trap groove formed on a portion of the sliding shaft outside the bearing member in the axial direction and coated with a lubricant;
A cap member having a width dimension larger than the movement distance of the dust trap groove in the axial direction and fixedly provided at an end of the bearing member so as to cover the outer peripheral side of the dust trap groove in a close proximity; ,
Sewing machine bearing structure characterized by comprising   The dust trap groove is formed to have a width that is larger than the moving distance of the sliding shaft in the axial direction, and the cap member enters the dust trap groove and dust traps from the gap between the cap member and the sliding shaft. 5. The bearing structure for a sewing machine according to claim 4, further comprising an annular protrusion that moves dust that has entered the groove in a direction away from the bearing member.   The bearing structure for a sewing machine according to claim 1 or 4, wherein the dust trap groove is composed of a plurality of annular grooves formed in an axially spaced manner.

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