JP2013070919A - Sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sewing machine that can easily adjust a feeding amount of a feed dog.SOLUTION: A vertical feeding mechanism 26 comprises an eccentric mechanism part 40. The eccentric mechanism part 40 comprises an eccentric shaft supporting part 70 and a base part 80. The eccentric shaft supporting part 70 comprises an eccentric shaft 72 and a rotating shaft 73. The base part 80 comprises a shaft fixing hole 84 and a fixing hole 85. A vertical feeding shaft 27 is inserted and fixed in the shaft fixing hole 84. The rotating shaft 73 of the eccentric shaft supporting part 70 is rotatably supported in the fixing hole 85. The eccentric shaft supporting part 70 is arranged to be able to rotate about the fixing hole 85. The eccentric shaft 72 is eccentric to the vertical feeding shaft 27 inserted and fixed in the shaft fixing hole 84. An operator can change a distance between the center of the shaft fixing hole 84 and the center of the eccentric shaft 72 by rotating the eccentric shaft supporting part 70. The operator can easily adjust the eccentricity of the eccentric shaft 73 to the vertical feeding shaft 27. Therefore, the operator can easily adjust the amount of reciprocal movement in the vertical directions of a feed dog.

Description

  The present invention relates to a sewing machine having a feed base for supporting a feed dog.

  The sewing machine imparts horizontal and vertical movements to the feed table that supports the feed dog. The feed dog performs a feed movement having a substantially elliptical locus. Therefore, the sewing machine can feed the cloth by the feed dog. Changing the feed momentum in the vertical direction affects the quality of the sewing product. When sewing conditions such as the type and thickness of the cloth to be sewn change, the operator needs to change the feed momentum by changing the substantially elliptical trajectory of the feed dog. Adjustment of the feed momentum required skilled skills, and it was difficult to obtain the quality of the sewing product as required. For example, in a cloth feed device for a sewing machine disclosed in Patent Document 1, an eccentric cam in which a lower end of a vertical feed arm is loosely fitted has a double eccentric cam structure, and the maximum momentum in the vertical direction of the feed dog is variable.

JP 2001-162076 A

  The double eccentric cam structure is eccentric at two locations. The operator has to calculate the total amount of eccentricity in consideration of the amount of eccentricity at each eccentric position. Therefore, adjustment of the feed momentum of the feed dog has been complicated and not easy.

  An object of the present invention is to provide a sewing machine that can easily adjust the feed momentum of the feed dog.

  The sewing machine according to the first aspect of the present invention inserts and fixes a feed base that supports the feed dog substantially horizontally, a vertical feed shaft that rotates in conjunction with the rotation of the main shaft, and one end of the vertical feed shaft. An eccentric mechanism having a shaft fixing hole and an eccentric shaft that is eccentric with respect to the center of the shaft fixing hole, and a vertical feed arm that pivotally supports one end of the eccentric shaft and imparts a vertical motion to the feed base. The eccentric mechanism portion includes an eccentric shaft support portion that supports the eccentric shaft so as to be movable in a direction perpendicular to the axial direction of the vertical feed shaft with respect to the center of the shaft fixing hole. .

  In the sewing machine of the first aspect, the eccentric mechanism portion supports the eccentric shaft so as to be movable with respect to the vertical feed shaft fixed to the shaft fixing hole. Therefore, the sewing machine can freely adjust the amount of eccentricity of the eccentric shaft relative to the vertical feed shaft when the eccentric mechanism is viewed from the axial direction of the vertical feed shaft. Therefore, the operator can easily adjust the amount of reciprocation of the feed dog in the vertical direction.

  In the first aspect, the eccentric shaft support portion includes a main body portion projecting the eccentric shaft in one direction orthogonal to the longitudinal direction at one end portion in a long longitudinal direction, and the one end portion of the main body portion. And the other end portion on the opposite side to the one direction and a shaft support portion protruding in the other direction opposite to the one direction, the eccentric mechanism portion, the shaft support portion for pivotally supporting the shaft support portion, You may further provide the fixing | fixed part which fixes the said pivotally supported part with respect to the said pivotally supported part so that rotation is impossible. The eccentric mechanism part pivotally supports the pivoted support part in the pivotal support part so as to be rotatable. Therefore, since the position of the eccentric shaft with respect to the vertical feed shaft is changed by rotating the eccentric shaft support portion around the shaft support portion, the eccentric amount of the eccentric shaft can be freely adjusted. Furthermore, since the fixed portion can fix the pivot support portion to the shaft support portion so as not to rotate, it is possible to prevent the eccentric amount of the eccentric shaft from changing during the operation of the feed dog.

  In the first aspect, the shaft support portion is formed in a cylindrical shape, and has an inner peripheral surface that is in close contact with the outer peripheral surface of the pivoted support portion, and a slit groove that extends from the inner peripheral surface to the fixed portion along the axis of the cylinder. The fixing portion is provided in a direction orthogonal to the direction in which the slit groove extends, and a first screw hole that penetrates the slit groove and a threaded engagement with the screw hole to penetrate the slit groove. A first screw that narrows the width of the slit groove, and the first screw is screwed into the first screw hole to narrow the width of the slit groove, thereby reducing the inner peripheral surface of the shaft support portion. You may make it fix to the outer peripheral surface of a to-be-supported part so that rotation is impossible. The shaft support has a slit structure. Therefore, the fixed part can be fixed by narrowing the width of the slit groove so that the inner peripheral surface of the shaft support part is brought into close contact with the outer peripheral surface of the shaft support part. Can be fixed.

  Further, in the first aspect, the shaft support portion includes at least one flat portion on an outer peripheral surface, the shaft support portion includes a second screw hole penetrating toward the outer peripheral surface of the shaft support portion, and the fixing portion is You may make it provide the 2nd screw which positions and fixes the said to-be-supported part to a predetermined position with respect to the said axial support part by screwing and engaging the said 2nd screw hole. For example, for the D-cut flat part, the second screw is fastened to the second screw hole provided in the shaft support part and the tip of the second screw is applied to the flat part, so that the fixed part is attached to the shaft support part. On the other hand, the pivoted support portion can be easily positioned at a predetermined position.

  In the first aspect, the vertical feed arm may include a ball bearing at a portion that supports one end of the eccentric shaft. The sewing machine can reduce the installation space of the vertical feed arm by using a ball bearing as a part where one end of the eccentric shaft of the vertical feed arm is loosely fitted.

The perspective view of the sewing machine 1. FIG. FIG. 3 is an enlarged perspective view in the vicinity of a sewing needle 8 and a needle plate 15. The perspective view of the cloth feed mechanism 30. FIG. FIG. 3 is an exploded perspective view of the vertical feed mechanism 26. The exploded perspective view of the eccentric mechanism part 40. FIG. The figure which shows the positional relationship of the 1st state of the eccentric mechanism part. The figure which shows the positional relationship of the 2nd state of the eccentric mechanism part. The perspective view of the eccentric shaft support part 170. FIG. The figure which shows the positional relationship of the 3rd state of the eccentric mechanism part 140. FIG. The figure which shows the positional relationship of the 4th state of the eccentric mechanism part 140. FIG.

  Hereinafter, a sewing machine 1 according to a first embodiment of the present invention will be described with reference to the drawings. The configuration of the sewing machine 1 will be described with reference to FIGS. The upper side, lower side, right side, left side, front side, and rear side of FIGS. 1 and 2 are the upper side, lower side, right side, left side, front side, and rear side of the sewing machine 1, respectively.

  The sewing machine 1 includes a bed 2, a pedestal 3, and an arm 4. The bed part 2 is a base of the sewing machine 1. The bed 2 is mounted from above on a recess (not shown) on the upper surface of the table 20. The pedestal 3 extends vertically upward from the right end of the bed 2. The arm portion 4 extends leftward from the upper end of the pedestal column portion 3. The arm part 4 faces the upper surface of the bed part 2. The arm portion 4 is provided with a presser foot 17 below the left end portion. The arm portion 4 holds a needle bar 7 therein. The needle bar 7 has a sewing needle 8 (see FIG. 2) attached to the lower end. The needle bar 7 and the sewing needle 8 reciprocate up and down as the main motor 13 is driven. The arm portion 4 includes a balance 9 in front of the left end portion. The balance 9 moves up and down in conjunction with the needle bar 7. The arm unit 4 includes an operation unit 10 at the top. The operation unit 10 includes a liquid crystal panel 11 on the front surface. The operator operates the operation unit 10 while looking at the liquid crystal panel 11 and inputs various instructions to the sewing machine 1.

  The sewing machine 1 includes a control device 29 on the lower surface of the table 20. The control device 29 is connected to the stepping pedal 22 via the rod 21. The operator operates the pedal 22 to the toe side or the heel side. The control device 29 controls the operation of the sewing machine 1 according to the operation direction and the operation amount of the pedal 22.

  The pedestal 3 has a main motor 13 at the upper right side. The arm portion 4 includes a main shaft 14 inside. The main shaft 14 extends in the left-right direction inside the arm portion 4 in a rotatable state. The right end of the main shaft 14 is connected to the main motor 13. The left end of the main shaft 14 is connected to a needle bar vertical movement mechanism (not shown). The main motor 13 drives the main shaft 14 to move the needle bar 7 and the balance 9 up and down.

  As shown in FIG. 2, the bed portion 2 includes a needle plate 15 at the upper left end. The needle plate 15 has a needle hole 18 in a substantially central portion. The lower end of the sewing needle 8 passes through the needle hole 18 when lowered. The needle plate 15 is provided with a feed dog hole 19 on each of the left, rear and right sides of the needle hole 18. The feed dog hole 19 has a rectangular shape that is long in the front-rear direction. The bed portion 2 includes a shuttle mechanism (not shown) and a cloth feed mechanism 30 (see FIG. 3) below the needle plate 15.

  The configuration of the cloth feed mechanism 30 will be described with reference to FIG. The upper side, lower side, right side, left side, front side, and rear side of FIG. 3 are the upper side, lower side, right side, left side, front side, and rear side of the cloth feed mechanism 30, respectively. The cloth feed mechanism 30 includes a feed base 33, a feed dog 34, a horizontal feed mechanism 25, a vertical feed mechanism 26, and the like. The feed base 33 is located below the needle plate 15 (see FIG. 2) and is substantially parallel to the needle plate 15. The feed base 33 supports three feed teeth 34 near the center of the upper surface. Each of the feed dogs 34 corresponds to the position of the feed dog hole 19. Each of the feed dogs 34 is long in the front-rear direction. The length of the feed dog 34 in the front-rear direction is smaller than the length of the feed dog hole 19. The feed dog 34 is provided with irregularities for sandwiching the cloth with the presser foot 17 in the upper part.

  The horizontal feed mechanism 25 will be described with reference to FIG. The horizontal feed mechanism 25 includes a cloth feed motor 62, a link mechanism portion 65, a horizontal feed shaft 28, a link member 50, and the like. The cloth feed motor 62 is arranged on the right side of the feed base 33. The cloth feed motor 62 is a stepping motor. The link mechanism 65 includes an intermediate action arm 68, a feed arm 66, and a feed arm 67. One end of the feed arm 66 is attached perpendicular to the tip of the drive shaft 63 of the cloth feed motor 62. The other end of the feed arm 66 is rotatably connected to one end of the feed arm 67 via a connecting portion 97. The other end of the feed arm 67 is rotatably connected to the front end of the intermediate working arm 68 in the extending direction via a connecting portion 96. The intermediate working arm 68 has the right end of the horizontal feed shaft 28 attached to the end opposite to the connecting portion with the connecting portion 96. The horizontal feed shaft 28 is rotatably provided on the upper left side of the cloth feed motor 62. The horizontal feed shaft 28 extends in the left-right direction. When the drive shaft 63 reciprocates, the connecting portion 97 reciprocates up and down. The connecting portion 96 is interlocked with the movement of the connecting portion 97 by the feed arm 67. The intermediate working arm 68 swings around the side on which the horizontal feed shaft 28 is attached. The horizontal feed shaft 28 rotates within a predetermined angle range as the intermediate working arm 68 swings. The lower end of the link member 50 is attached perpendicular to the left end portion of the horizontal feed shaft 28. The upper end of the link member 50 is rotatably connected to a shaft support portion 36 at the front end portion of the feed base 33. Therefore, the feed base 33 reciprocates in the front-rear direction of the sewing machine 1 via the link member 50 when the horizontal feed shaft 28 rotates within a predetermined angle range.

  The vertical feed mechanism 26 will be described with reference to FIG. The upper side, lower side, right side, left side, front side, and rear side of FIG. 4 are the upper side, lower side, right side, left side, front side, and rear side of the cloth feed mechanism 30, respectively. The vertical feed mechanism 26 includes a vertical feed shaft 27, an eccentric mechanism 40, a ball bearing 60, a vertical feed arm 51, and the like. The vertical feed shaft 27 is positioned parallel to the horizontal feed shaft 28. The vertical feed shaft 27 includes a pulley 24 (see FIG. 3) at the right end. The pulley 24 is connected to the main shaft 14 (see FIG. 1) by a timing belt (not shown). The vertical feed shaft 27 is rotated by driving the main motor 13 through a timing belt connected to the main shaft 14. Therefore, the vertical feed shaft 27 rotates in synchronization with the main shaft 14 of the sewing machine 1. The eccentric mechanism 40 is provided at the left end of the vertical feed shaft 27. The eccentric mechanism unit 40 includes an eccentric shaft 72. The eccentric shaft 72 is eccentric with respect to the axis of the vertical feed shaft 27. Details of the eccentric mechanism 40 and the eccentric shaft 72 will be described later. The vertical feed arm 51 is connected to the shaft support portion 35 of the feed base 33. The shaft support portion 35 is provided at the rear end portion of the feed base 33. The vertical feed arm 51 rotatably holds an eccentric shaft 72 of the eccentric mechanism 40 via a ball bearing 60 described later. The eccentric mechanism 40 rotates with the rotation of the vertical feed shaft 27. The eccentric shaft 72 rotates while moving up and down by the rotation of the eccentric mechanism portion 40. The vertical feed arm 51 moves up and down. Therefore, the vertical feed mechanism 26 can move the feed base 33 up and down.

  The structure of the vertical feed arm 51 will be described with reference to FIG. The vertical feed arm 51 is substantially cylindrical. The vertical feed arm 51 includes a holding hole 55, a mounting base 52, a mounting portion 53, and a shaft fixing portion 54. The holding hole 55 penetrates in the left-right direction. The holding hole 55 inserts and holds the ball bearing 60. Details of the ball bearing 60 will be described later. The mounting base 52 is provided on the outer peripheral surface of the vertical feed arm 51. The attachment portion 53 is provided on the upper portion of the attachment base 52. The attachment portion 53 has a cylindrical shape and extends in the axial direction of the holding hole 55. The attachment portion 53 includes an attachment hole 56. The shaft fixing portion 54 is provided orthogonal to the attachment portion 53. The shaft fixing portion 54 includes a screw hole 57. The screw hole 57 passes through the attachment hole 56 of the attachment portion 53.

  In the vertical feed arm 51, the position of the attachment hole 56 of the attachment portion 53 corresponds to the position of the through hole 35 </ b> A provided in the shaft support portion 35 of the feed base 33. The fixing pin 45 is fitted into the through hole 35 </ b> A and the attachment hole 56. The screw 47 is fastened to the screw hole 57. The tip of the screw 47 abuts on the tip of the fixing pin 45. The distal end portion of the fixing pin 45 is fixed to the attachment portion 53. The feed base 33 can be rotated by a fixed pin 45. The feed base 33 and the vertical feed arm 51 are connected.

  The structure of the eccentric mechanism 40 will be described with reference to FIG. The eccentric mechanism part 40 includes an eccentric shaft support part 70 and a base part 80. The eccentric shaft support portion 70 will be described. The eccentric shaft support portion 70 includes a main body portion 71, an eccentric shaft 72, and a rotation shaft 73. The main body 71 has a plate shape having a length in one direction. Corners at both ends in the longitudinal direction of the main body 71 are arcuate. The main body 71 has one surface 71A and another surface 71B. One surface 71A is a surface facing the feed base 33 (see FIG. 4). The other surface 71B is a surface opposite to the one surface 71A and is a surface facing the vertical feed shaft 27 (see FIG. 4) side. The eccentric shaft 72 is provided on one end side in the longitudinal direction of the main body 71 on one surface 71A. The rotation shaft 73 is provided on the other end side in the longitudinal direction of the main body 71 on the other surface 71B. The eccentric shaft 72 and the rotation shaft 73 extend in a direction orthogonal to the longitudinal direction of the main body 71 and in directions opposite to each other. The eccentric shaft 72 and the rotation shaft 73 are, for example, cylindrical or columnar.

  The base unit 80 will be described. As shown in FIG. 5, the base portion 80 includes a pedestal portion 81, a shaft support portion 82, and a shaft fixing portion 83. The pedestal portion 81 is partially cylindrical. The pedestal portion 81 extends parallel to the axial direction of the vertical feed shaft 27. The pedestal portion 81 includes one end surface 81A, an outer peripheral surface 81B, and the other end surface 81C. One end surface 81A is a surface facing the eccentric shaft support portion 70 side. The outer peripheral surface 81B is partially arc-shaped. The other end surface 81C is a surface opposite to the one end surface 81A and is opposed to the vertical feed shaft 27 side. The pedestal 81 has a shaft fixing hole 84. The shaft fixing hole 84 penetrates along the axial direction of the pedestal portion 81. The shaft fixing hole 84 inserts one end of the vertical feed shaft 27 from the other end surface 81C side. The pedestal portion 81 has screw holes 81D and 81E orthogonal to the axial direction of the shaft fixing hole 84 on the outer peripheral surface 81B. The screw hole 81D communicates with the shaft fixing hole 84 perpendicular to the screw hole 81E. The pedestal portion 81 fastens the screws 91 and 92 in the screw holes 81D and 81E. The screws 91 and 92 abut against one end of the vertical feed shaft 27 inserted in the shaft fixing hole 84 to fix the vertical feed shaft 27 to the base portion 80. The base portion 80 rotates integrally with the vertical feed shaft 27.

  The shaft support portion 82 is provided at a position facing the circular arc portion of the outer peripheral surface 81B with the shaft fixing hole 84 interposed therebetween. The shaft support 82 is cylindrical. The shaft support portion 82 extends in parallel to the extending direction of the pedestal portion 81. The shaft support portion 82 includes a fixing hole 85. The fixing hole 85 inserts and fixes the rotation shaft 73 of the eccentric shaft support part 70. The fixing hole 85 is parallel to the axial direction of the shaft fixing hole 84. The shaft support 82 has a slit structure. The shaft support 82 includes a slit groove 86. The slit groove 86 is parallel to the axial direction of the fixing hole 85. The shape of the shaft support 82 viewed from the side of the eccentric shaft support 70 is “C”.

  The shaft fixing portion 83 is provided integrally with the shaft support portion 82 in the vicinity of the slit groove 86 of the shaft support portion 82. The shaft fixing portion 83 has a cylindrical shape orthogonal to the axial direction of the shaft support portion 82. The shaft fixing portion 83 includes a screw hole 87 and a cutting groove 88. The screw hole 87 is provided along the axial direction of the shaft fixing portion 83. The cutting groove 88 communicates with the cutting groove 86. The shaft fixing portion 83 is divided into two in the axial direction in the cutting groove 88. As will be described later, the shaft fixing portion 83 has a function of narrowing the internal space of the shaft support portion 82 in order to fix the rotation shaft 73 inserted into the fixing hole 85 of the shaft support portion 82.

  The assembly of the eccentric mechanism 40 will be described. One end surface 81 </ b> A of the base portion 80 faces the other surface 71 </ b> B of the main body portion 71 of the eccentric shaft support portion 70. The base portion 80 inserts the rotation shaft 73 of the eccentric shaft support portion 70 into the fixing hole 85. The eccentric shaft support portion 70 can be rotated around a rotation shaft 73 inserted into the fixing hole 85. The eccentric amount of the eccentric shaft 72 with respect to the vertical feed shaft 27 can be adjusted by rotating the eccentric shaft support portion 70. A method for adjusting the amount of eccentricity will be described later.

  The shaft fixing portion 83 fastens the screw 90 in the screw hole 87. The groove width of the slit groove 86 is narrowed together with the groove width of the cutting groove 88. The inner diameter of the fixing hole 85 of the shaft support portion 82 becomes smaller. The inner peripheral surface of the fixing hole 85 is in close contact with the outer peripheral surface of the rotation shaft 73. Therefore, the rotation shaft 73 can be firmly fixed to the shaft support portion 82. The eccentric shaft support part 70 and the base part 80 are fixed. The assembly of the eccentric mechanism 40 is completed.

  The connection structure of the eccentric mechanism 40 and the vertical feed arm 51 will be described with reference to FIG. The holding hole 55 of the vertical feed arm 51 inserts and holds the ball bearing 60. The ball bearing 60 may employ a known structure in which, for example, a ball is surrounded by an outer ring and an inner ring, and a load is transmitted through the ball. The ball bearing 60 inserts the eccentric shaft 72 of the eccentric shaft support portion 70 of the eccentric mechanism portion 40 into the hole 61 of the inner ring. When the eccentric shaft 72 rotates, the inner ring rotates and the ball rotates. As the ball rotates, the friction generated between the vertical feed arm 51 and the eccentric shaft support 70 is lower than the rotation of the eccentric shaft 72 in direct contact with the inner peripheral surface of the holding hole 55 of the vertical feed arm 51. it can. The ball bearing 60 is compact. Therefore, the size of the vertical feed arm 51 does not increase. The vertical feed arm 51 can be installed in the bed portion 2 having a narrow internal space. The eccentric shaft 72 has a screw hole (not shown) in the axial direction. The ball bearing 60 is positioned and fixed by screwing a screw 46 with a flange into the screw hole of the eccentric shaft 72.

  The relationship between the adjustment of the amount of eccentricity in the eccentric mechanism 40 and the movement locus K of the feed base 33 will be described with reference to FIGS. The eccentric shaft support portion 70 can rotate around a rotation shaft 73 inserted into the fixing hole 85 of the base portion 80. When viewed from the axial direction of the vertical feed shaft 27, the center of the shaft fixing hole 84, the center of the eccentric shaft 72, and the center of the fixing hole 85 (rotating shaft 73) are P1, P2, and P3, respectively. The eccentric shaft support portion 70 shown in FIG. 6 is in a first state where the center P2 of the eccentric shaft 72 is on a straight line connecting P1 and P3. P2 is closest to P1. The distance Q1 between P1 and P2 is the minimum distance in the eccentric mechanism unit 40. When the distance Q1 between P1 and P2 is the minimum, the amount of eccentricity in the eccentric mechanism unit 40 is the minimum. The movement locus K1 of the feed dog 34 when the eccentric amount of the eccentric mechanism 40 is adjusted to Q1 is shown below the arrow in FIG. The movement trajectory K1 has a horizontally long substantially oval shape above and below the position of the needle plate 15 (H in the figure). The feed dog 34 feeds the cloth when the movement locus K1 is above the needle plate 15.

  The eccentric shaft support portion 70 shown in FIG. 7 is in a second state in which the center P2 of the eccentric shaft 72 is separated from the straight line connecting P1 and P3. In the second state, the eccentric shaft support portion 70 rotates, for example, about 10 ° counterclockwise (in FIG. 7) about P3 that is the center of the rotation shaft 73 from the first state shown in FIG. ing. Compared to the first state, the eccentric shaft 72 is located away from the vertical feed shaft 27. The distance Q2 between P1 and P2 is longer than the distance Q1 between P1 and P2 in the first state. The amount of eccentricity in the eccentric mechanism 40 is greater than in the first state. The movement locus K2 of the feed dog 34 when the eccentric amount of the eccentric mechanism 40 is adjusted to Q2 is shown below the arrow in FIG. The motion trajectory K2 has a substantially elliptical shape that swells greatly in the vertical direction compared to the motion trajectory K1. The amount of movement of the feed dog 34 in the vertical direction increases compared to the first state. Therefore, the eccentric mechanism portion 40 easily rotates with the eccentric shaft support portion 70 around the rotation shaft 73 inserted into the fixing hole 85 of the base portion 80, so that the eccentric amount of the eccentric shaft 72 with respect to the vertical feed shaft 27 can be easily achieved. Can be adjusted.

  The rotation shaft 73 of the eccentric shaft support portion 70 is an example of the “supported portion” of the present invention. The shaft support portion 82 of the base portion 80 is an example of the “shaft support portion” in the present invention. The shaft fixing portion 83 of the base portion 80 is an example of the “fixing portion” in the present invention.

  As described above, the sewing machine 1 of this embodiment includes the cloth feeding mechanism 30. The cloth feed mechanism 30 includes a vertical feed mechanism 26. The vertical feed mechanism 26 moves the feed base 33 up and down. The vertical feed mechanism 26 includes an eccentric mechanism 40. The eccentric mechanism part 40 includes an eccentric shaft support part 70 and a base part 80. The eccentric shaft support part 70 includes an eccentric shaft 72 and a rotation shaft 73. The base portion 80 includes a shaft fixing hole 84 and a fixing hole 85. The vertical feed shaft 27 is inserted and fixed in the shaft fixing hole 84. The rotation shaft 73 of the eccentric shaft support portion 70 is rotatably supported in the fixing hole 85. The eccentric shaft support portion 70 can rotate about a rotation shaft 73 that is pivotally supported by the fixing hole 85. The eccentric shaft 72 is eccentric with respect to the vertical feed shaft 27 inserted and fixed in the shaft fixing hole 84. The operator can change the distance between the center P1 of the shaft fixing hole 84 and the center P2 of the eccentric shaft 72 by rotating the eccentric shaft support portion 70. The distance between P1 and P2 is easy to confirm and easy to adjust. The operator can easily adjust the amount of eccentricity of the eccentric shaft 72 with respect to the vertical feed shaft 27. Therefore, the operator can easily adjust the amount of reciprocation of the feed dog in the vertical direction.

  Particularly in the present embodiment, the fixing hole 85 of the base portion 80 is provided in the shaft support portion 82. The shaft support 82 has a slit structure. By narrowing the width of the slit groove 86, the inner peripheral surface of the shaft support portion 82 can be tightly fixed to the outer peripheral surface of the rotating shaft 73. The sewing machine 1 can securely fix the rotation shaft 73 to the shaft support portion 82 so as not to rotate.

  In the present embodiment, in particular, a portion in which one end portion of the eccentric shaft 72 in the vertical feed arm 51 is loosely fitted is constituted by the ball bearing 60. Therefore, the sewing machine 1 can reduce the installation space for the upper and lower feed arms 51 in the bed portion 2.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation is possible. In the above embodiment, the eccentric mechanism portion 40 has the eccentric shaft support portion 70 rotated with respect to the base portion 80. The operator rotates the eccentric shaft support portion 70 to change the distance between the center P1 of the shaft fixing hole 84 and the center P2 of the eccentric shaft 72, so that the eccentric amount of the eccentric shaft 72 with respect to the vertical feed shaft 27 is free. Adjust to. For example, the eccentric mechanism 40 may have a structure that can be instantaneously adjusted to an eccentric amount selected from an eccentric amount pattern that can be adjusted by the eccentric shaft support 70.

  An eccentric mechanism 140 that can be instantaneously adjusted to a predetermined eccentricity pattern will be described with reference to FIGS. The eccentric mechanism 140 is a modification of the eccentric mechanism 40 of the above embodiment. As shown in FIGS. 8 and 9, the eccentric mechanism 140 includes an eccentric shaft support 170 and a base 180. The eccentric shaft support portion 170 includes a main body portion 171, an eccentric shaft 172, and a rotation shaft 173. The main body 171 and the eccentric shaft 172 are the same as the main body 71 and the eccentric shaft 72 shown in FIG. The pivot shaft 173 includes a first flat surface 176 and a second flat surface 177. The first flat surface 176 and the second flat surface 177 are formed on the outer peripheral surface of the rotating shaft 173 by D-cut processing. The second flat surface 177 is provided at a position shifted in the circumferential direction from the end of the rotation shaft 173 on the opposite side in the radial direction with respect to the first flat surface 176. The first flat surface 176 and the second flat surface 177 are not parallel in the axial direction of the rotation shaft 173.

  As shown in FIG. 9, the base portion 180 includes a pedestal portion 181 and a shaft support portion 182. The pedestal 181 has a shaft fixing hole 184. The shaft fixing hole 184 corresponds to the shaft fixing hole 84 shown in FIG. The shaft fixing hole 184 inserts and fixes one end of the vertical feed shaft 27. The shaft support 182 is provided on the pedestal 181. The shaft support 182 has a prismatic shape. The shaft support 182 extends parallel to the extending direction of the pedestal 181. The shaft support 182 includes a fixing hole 185. The fixing hole 185 corresponds to the fixing hole 85 shown in FIG. The fixing hole 185 inserts the rotation shaft 173 of the eccentric shaft support portion 170.

  The shaft support portion 182 includes side surfaces 187, 188, and 189 that are parallel to the axial direction of the fixing hole 185. The side surface 187 is positioned on a straight line connecting the center of the shaft fixing hole 184 and the center of the fixing hole 185. The side surfaces 188 and 189 are orthogonal to the side surface 187 and parallel to each other. The side surfaces 187 to 189 have screw holes 201 to 203, respectively. Each screw hole 201 to 203 communicates perpendicularly to the axial direction of the fixing hole 185.

  As shown in FIGS. 9 and 10, the eccentric shaft support portion 170 rotates around a rotation shaft 173 inserted into the fixing hole 185 with respect to the base portion 180. As shown in FIG. 9, the screw 94 is fastened to the screw hole 202 of the side surface 188. The first flat surface 176 of the rotating shaft 173 inserted into the fixing hole 185 contacts the tip of the screw 94. The center of the fixing hole 185, the center of the shaft fixing hole 184, and the center of the eccentric shaft 172 are located on the same straight line. The eccentric shaft support 170 is in the third state. In the third state, the eccentric amount of the eccentric shaft 172 with respect to the shaft fixing hole 184 is the smallest positional relationship. The screw 93 is fastened to the screw hole 201 on the side surface 187. The tip of the screw 93 comes into contact with the outer peripheral surface of the rotating shaft 173 inserted into the fixing hole 185. The rotation shaft 173 cannot be rotated. The eccentric shaft support 170 can maintain the third state.

  As shown in FIG. 10, the eccentric shaft support portion 170 rotates counterclockwise (in FIG. 10) around the rotation shaft 173 inserted into the fixing hole 185 with respect to the base portion 180. The screw 95 is fastened to the screw hole 202 of the side surface 189. The second flat surface 177 of the rotating shaft 173 inserted into the fixing hole 185 contacts the tip of the screw 95. The center of the eccentric shaft 172 is deviated from the straight line connecting the center of the fixing hole 185 and the center of the shaft fixing hole 184. The eccentric shaft support 170 is in the fourth state. In the fourth state, the eccentric amount of the eccentric shaft 172 with respect to the shaft fixing hole 184 is larger than that in the third state. The screw 93 is fastened to the screw hole 201 on the side surface 187. The tip of the screw 93 comes into contact with the outer peripheral surface of the rotating shaft 173 inserted into the fixing hole 185. The rotation shaft 173 cannot be rotated. The eccentric shaft support part 170 can maintain the fourth state.

  As described above, in this modification, the eccentric mechanism 140 has the first flat surface 176 and the second flat surface 177 on the rotation shaft 173 of the eccentric shaft support 170. The eccentric shaft support portion 170 rotates around the rotation shaft 173 inserted in the fixing hole 185, and the tip of the screw 94 or the screw 95 is brought into contact with the first flat surface 176 or the second flat surface 177. The amount of eccentricity of the eccentric shaft 172 relative to the shaft fixing hole 184 can be adjusted to a predetermined eccentricity pattern by contacting the tip of the screw 95 with the first flat surface 176 or the second flat surface 177. The operator does not need to measure the distance between the center of the fixing hole 185 and the center of the eccentric shaft 172 and can accurately adjust the distance to a predetermined eccentricity, so that a technical error by the operator is less likely to occur. The amount of eccentricity can be changed by the angle formed by the flat surfaces provided on the rotating shaft 173. The rotating shaft 173 of this modification includes two flat surfaces, but may be three or more. In this case, the eccentric mechanism unit can be changed to a pattern having a larger amount of eccentricity.

  The horizontal feed mechanism 25 is not limited to the above embodiment. For example, the horizontal feed mechanism 25 may be driven not by the cloth feed motor 62 and the link mechanism portion 65 but by a crank mechanism connected to the main shaft 14 or the vertical feed shaft 27 that is rotated by driving the main motor 13. In this case, the horizontal feed mechanism 25 rotates the horizontal feed shaft 28 within a predetermined angle range by the crank mechanism. The feed base 33 reciprocates in the front-rear direction of the sewing machine 1 through the link member 50 by the rotation of the horizontal feed shaft 28 within a predetermined angle range.

  The upper and lower feed arm 51 is configured by the ball bearing 60 at a portion where one end of the eccentric shaft 72 is loosely fitted, but may be configured by another bearing such as a needle bearing.

DESCRIPTION OF SYMBOLS 1 Sewing machine 14 Main shaft 26 Vertical feed mechanism 27 Vertical feed shaft 33 Feed base 34 Feed dog 40 Eccentric mechanism portion 51 Vertical feed arm 60 Ball bearing 70 Eccentric shaft support portion 71 Main body portion 72 Eccentric shaft 73 Rotating shaft 80 Base portion 82 Axis Support portion 83 Shaft fixing portion 84 Shaft fixing hole 85 Fixing hole 86 Split groove 87 Screw hole 88 Cutting groove 90, 94, 95 Screw 140 Eccentric mechanism portion 170 Eccentric shaft support portion 173 Rotating shaft 176 First flat surface 177 Second flat end surface 180 Base 202, 203 Screw hole

Claims (5)

A feed base for supporting the feed dog substantially horizontally;
A vertical feed shaft that rotates in conjunction with the rotation of the spindle,
An eccentric mechanism having a shaft fixing hole for inserting and fixing one end of the vertical feed shaft, and an eccentric shaft eccentric with respect to the center of the shaft fixing hole;
In a sewing machine provided with a vertical feed arm that pivotally supports one end of the eccentric shaft and imparts vertical movement to the feed base,
The eccentric mechanism section includes an eccentric shaft support portion that supports the eccentric shaft so as to be movable in a direction orthogonal to the axial direction of the vertical feed shaft with respect to the center of the shaft fixing hole. The eccentric shaft support is
A main body that projects the eccentric shaft in one direction orthogonal to the longitudinal direction at one end in the longitudinal direction;
The other end portion of the main body portion opposite to the one end portion is provided with a pivot support portion protruding in the other direction opposite to the one direction,
The eccentric mechanism portion is
A shaft support that pivotally supports the pivoted support, and
The sewing machine according to claim 1, further comprising a fixing portion that fixes the shaft support portion so as not to rotate with respect to the shaft support portion. The shaft support is formed in a cylindrical shape,
An inner peripheral surface that is in close contact with the outer peripheral surface of the pivot support;
A slit groove extending from the inner peripheral surface to the fixed portion along the axis of the cylinder,
The fixing part is
A first screw hole provided in a direction orthogonal to the extending direction of the slit groove, and penetrating the slit groove;
A first screw that narrows the width of the slit groove by threading into the first screw hole and penetrating the slit groove;
When the first screw is screwed into the first screw hole to narrow the width of the slit groove, the inner peripheral surface of the shaft support portion is brought into close contact with the outer peripheral surface of the shaft support portion and is fixed so as not to rotate. The sewing machine according to claim 2, wherein: The pivoted support portion includes at least one flat portion on an outer peripheral surface;
The shaft support portion includes a second screw hole penetrating toward the outer peripheral surface of the shaft support portion,
The fixing portion includes a second screw that positions and fixes the shaft support portion at a predetermined position with respect to the shaft support portion by screwing into the second screw hole and contacting the flat portion. The sewing machine according to claim 2 or 3.   The sewing machine according to any one of claims 2 to 4, wherein the vertical feed arm includes a ball bearing at a portion that supports one end of the eccentric shaft.

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