CN212560679U - Cloth cutting device and sewing machine - Google Patents

Abstract

The utility model relates to a can maintain cloth cutting device and sewing machine of cutter to the stable cutting of cloth for a long time. The rotating arm is fixed to an output shaft of the motor, and a locking pin is provided at the eccentric portion. The eccentric portion is eccentric with respect to the axis of the output shaft. The clamping groove is arranged at the upper end of the connecting arm and extends along the horizontal direction. The clamping pin is clamped with the clamping groove. The working shaft is connected with the lower end of the connecting arm. A holding member is fixed to a lower end of the working shaft, and the cutter is held by the holding member. The guide block is provided at the lower end of the connecting arm. The guide groove is engaged with the guide block, and the guide groove guides the vertical movement of the connecting arm. The engagement pin transmits a vertical component of the driving force of the motor to the connection arm via the engagement groove, but does not transmit a horizontal component of the driving force to the connection arm. Therefore, the guide groove is not loaded in the horizontal direction.

Description

Cloth cutting device and sewing machine

Technical Field

The utility model relates to a cloth cutting device and sewing machine.

Background

There is a sewing machine capable of forming a cut hole such as a buttonhole in a cloth. The keyhole sewing machine disclosed in japanese patent laid-open publication No. 2015 100388 can sew a keyhole stitch for preventing enlargement of a buttonhole in a fabric. The buttonhole sewing machine drives a knife motor of the knife mechanism to lower the knife, and cuts the part of the cloth positioned at the inner side of the buttonhole stitch to form a buttonhole. The knife mechanism moves a knife drive shaft holding a knife at a lower end up and down via a link arm coupled to a motor shaft of a knife motor via an eccentric mass. The knife drive shaft has a rolling member. The rolling member moves along the vertically extending long hole, thereby being capable of guiding the vertical movement of the knife driving shaft. The link arm rotates in conjunction with the rotational action of the motor shaft. Therefore, the driving force transmitted to the blade driving shaft by the link arm has a vertical component and a horizontal component. The long hole restricts the left and right movement of the rolling member by its inner surface, and guides the up and down movement of the rolling member. The link arm presses the rolling member against the inner surface of the long hole by utilizing the left-right direction component in the driving force. Therefore, there is a possibility that: when the long hole and the rolling member are worn by the buttonhole sewing machine used for a long time, the knife driving shaft is shaken in the horizontal direction, and the buttonhole is formed unstably.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a can maintain cloth cutting device and sewing machine of cutter to the stable cutting of cloth for a long time.

The cloth cutting apparatus according to claim 1 comprises: a motor as a drive source; an eccentric portion connected to an output shaft of the motor, the eccentric portion being eccentric with respect to an axis of the output shaft; an arm portion having one end connected to the eccentric portion, the arm portion transmitting a driving force of the motor; a working shaft connected to the other end of the arm, the working shaft operating a cutter for cutting a cloth; and a holding portion provided at a lower end portion of the working shaft and holding the cutter by the holding portion, wherein the cloth cutting apparatus includes a conversion mechanism located between the eccentric portion and the one end portion of the arm portion, the conversion mechanism converting rotation of the output shaft of the motor into vertical motion of the working shaft, and the conversion mechanism includes: a groove portion extending in a horizontal direction; an engaging portion engaged with the groove portion; and a second end guide portion that vertically guides the second end portion of the arm portion, one of the groove portion and the engaging portion being provided in the eccentric portion, and the other of the groove portion and the engaging portion being provided in the arm portion. The direction of the driving force generated by the rotation of the motor output shaft has an up-down direction component and a horizontal direction component. Since the groove portion of the conversion mechanism extends in the horizontal direction, the groove portion and the engagement portion vertically abut each other and do not horizontally contact each other. Therefore, the conversion mechanism can transmit the vertical component of the driving force, but does not transmit the horizontal component. The arm portion does not move in the horizontal direction and does not generate horizontal resistance to the guide portion at the other end. Therefore, the cloth cutting device can prevent the abrasion, deformation and the like of the guide part at the other end, and the working shaft is not easy to shake along the horizontal direction even if the cloth cutting device is used for a long time. The cloth cutting device can maintain the stable cutting of the cutter to the cloth for a long time.

In the cloth cutting apparatus according to claim 2, the groove may be provided at the one end of the arm, the engaging portion may be provided at a position of the eccentric portion eccentric with respect to an axis of the output shaft, and the engaging portion may protrude toward the groove. The eccentric portion rotates together with an output shaft of the motor. The engaging portion revolves around the output shaft, and the engaging portion vertically abuts against the groove portion. The engaging portion protrudes from the eccentric portion. Therefore, even if the contact position of the engagement portion with the groove portion changes during the revolution, the engagement portion and the groove portion can be maintained in a state of vertical contact. Since the engagement portion and the groove portion vertically abut against each other, the conversion mechanism transmits a vertical component of the driving force. Since the engagement portion moves in the horizontal direction with respect to the groove portion and the engagement portion does not come into contact with the groove portion in the horizontal direction, the conversion mechanism does not transmit the horizontal component of the driving force. The cloth cutting device can prevent the abrasion, deformation and the like of the guide part at the other end.

The engaging portion of the cloth cutting apparatus according to claim 3 may protrude in parallel with the output shaft at the eccentric portion. The engagement portion protrudes in parallel with the output shaft, and therefore, the engagement portion can be brought into contact with the groove portion at a position between the root portion and the tip end of the protrusion, and the driving force can be efficiently transmitted to the groove portion.

The cloth cutting apparatus according to claim 4 or 5 may further include a square slider that is provided in the engaging portion and is rotatable with respect to the eccentric portion, and the square slider may be engaged with the groove portion and may be movable in the horizontal direction. The square slider is in surface contact with the groove portion, and the area in contact with the groove portion can be increased. Therefore, the engagement portion can transmit the driving force to the groove portion more efficiently.

The eccentric portion of the cloth cutting apparatus of claim 6 may be an eccentric wheel: the shaft center of the eccentric cam is eccentric with respect to the shaft center of the output shaft, the groove portion is provided at the one end portion of the arm portion, and the engaging portion is the eccentric cam. The eccentric rotates with the output shaft of the motor. Since the outer peripheral surface of the eccentric wheel and the groove portion vertically abut against each other, the conversion mechanism transmits a vertical component of the driving force. Since the eccentric cam and the groove do not abut on each other in the horizontal direction, the conversion mechanism does not transmit the horizontal component of the driving force. Therefore, the cloth cutting apparatus can prevent the abrasion, deformation, and the like of the other end guide portion. The conversion mechanism can make the eccentric part be a simpler structure of only an eccentric wheel.

The groove of the cloth cutting apparatus according to claim 7 may be provided in the eccentric portion so as to be rotatable with respect to the eccentric portion, and the engaging portion may be provided at the one end portion of the arm portion, may protrude toward the groove, and may extend parallel to the groove. The eccentric portion rotates together with an output shaft of the motor. The groove part revolves around the output shaft. The engaging portion extends parallel to the groove portion, and the engaging portion vertically abuts against the groove portion. Since the groove portion is rotatable, even if the groove portion revolves, the direction of the groove portion can be corrected by the engaging portion, and the direction of the groove in the horizontal direction can be maintained. Since the groove portion and the engagement portion vertically abut against each other, the conversion mechanism transmits a vertical component of the driving force. Since the groove portion moves in the horizontal direction with respect to the engagement portion, the conversion mechanism does not transmit the horizontal component of the driving force. Therefore, the cloth cutting apparatus can prevent the abrasion, deformation, and the like of the other end guide portion.

The other end guide portion of the cloth cutting apparatus according to claim 8 may be provided on the other end of the arm portion on a side opposite to the side where the connecting portion of the working shaft is provided. Therefore, the arm portion can be brought closer to the operating shaft, and the driving force generated by the driving of the motor can be efficiently transmitted to the operating shaft.

The cloth cutting apparatus according to claims 9 and 10 may further include a first end guide portion that vertically guides the one end portion of the arm portion, the holding portion may hold the cutter at a position closer to one side in a horizontal direction than a position of the lower end portion of the operating shaft, and the first end guide portion may be provided at the other side in the horizontal direction with respect to the one end portion of the arm portion. The holding part holds the cutter at a position closer to one side in the horizontal direction than the position of the lower end part of the working shaft. When the arm further moves the working shaft downward after the cutter comes into contact with the fabric when cutting the fabric, the working shaft is inclined toward the other side in the horizontal direction with the cutter as a fulcrum. One end guide is on the side where the working shaft is inclined. The one end guide portion supports one end portion of the arm portion against the action of the operating shaft to suppress the inclination of the operating shaft. Therefore, stress in the horizontal direction is not applied to the cutter.

The sewing machine according to claim 11 is characterized in that the sewing machine comprises: a cloth feeding device for feeding cloth in a horizontal direction; a needle bar equipped with a needle at a lower end thereof, the needle bar being capable of moving up and down; and the cloth cutting device according to any one of claims 1 to 10, wherein the cloth feeding device feeds the cloth in cooperation with the up-and-down movement of the needle bar to form a stitch on the cloth, and the cloth is cut by the cutter driven by the cloth cutting device, thereby forming a cut hole corresponding to the stitch. The sewing machine can obtain the same effect as the cloth cutting device of the technical scheme 1-10.

Drawings

Fig. 1 is a perspective view of the inside of the sewing machine 1.

Fig. 2 is a perspective view of the cloth cutting apparatus 100 when it is not in operation.

Fig. 3 is an exploded perspective view of the cloth cutting apparatus 100.

Fig. 4 is an operation diagram of the switching mechanism 180 when viewed from a main viewing angle after being cut along the line I-I in fig. 2.

Fig. 5 is a perspective view of the cloth cutting apparatus 100 in operation.

Fig. 6 is a perspective view of the cloth cutting apparatus 200.

Fig. 7 is a perspective view of the cloth cutting apparatus 300.

Fig. 8 is a perspective view of the cloth cutting apparatus 400.

Fig. 9 is a perspective view of the cloth cutting apparatus 500.

Fig. 10 is a perspective view of the cloth cutting apparatus 600.

Fig. 11 is a perspective view of the cloth cutting apparatus 700.

Fig. 12 is a perspective view of the cloth cutting apparatus 800.

Detailed Description

Embodiments of the present invention will be described with reference to the accompanying drawings. The following description uses left-right, front-back, and up-down as indicated by arrows in the drawings. The sewing machine 1 according to the present embodiment is a so-called keyhole sewing machine in which a keyhole stitch can be sewn to a fabric and a linear buttonhole can be formed in the center of the keyhole stitch.

As shown in fig. 1, the sewing machine 1 includes a bed 2, a column 3, an arm 4, a tip 5, a sewing machine motor 32, a cloth feeding device 50, and a cloth cutting device 100. The base unit 2 extends in the front-rear direction, and includes therein a lower shaft 21, a shuttle mechanism, a cloth feeding device 50, and the like. The column part 3 extends upward from the rear end side of the bed part 2, and includes a timing belt 31, a sewing machine motor 32, and the like therein. The arm portion 4 extends forward from the upper side of the column portion 3. The arm portion 4 faces the upper surface of the base portion 2 and has a spindle 41 and the like therein. The sewing machine motor 32 rotates the main shaft 41 in the clockwise direction in the main view.

The front end portion 5 is provided in front of the arm portion 4. The distal end portion 5 includes a thread take-up mechanism 60, a needle bar drive mechanism 70, and the like therein. The rear end of the main shaft 41 is connected to the sewing machine motor 32, and the front end of the main shaft 41 is connected to the thread take-up mechanism 60. The thread take-up mechanism 60 is connected to a needle bar drive mechanism 70 on the front side. The main shaft 41 transmits the driving force of the sewing machine motor 32 to the needle bar driving mechanism 70 and the thread take-up mechanism 60, thereby driving the needle bar driving mechanism 70 and the thread take-up mechanism 60. The thread take-up mechanism 60 includes a thread take-up lever 61, a thread take-up lever crank 62, and the like. The thread take-up lever 61 moves up and down at the time of sewing to lift up the upper thread. The thread take-up lever crank 62 is connected to the front end of the main shaft 41. The thread take-up lever crank 62 moves the thread take-up lever 61 up and down in accordance with the rotation of the main shaft 41.

The needle bar drive mechanism 70 includes a needle bar 71, a needle bar crank link 72, and the like. The needle bar 71 is a metal bar extending in the up-down direction, and is fitted with a needle at its lower end. The needle bar crank link 72 is connected to the needle bar 71 and the thread take-up lever crank 62 of the thread take-up mechanism 60. The needle bar drive mechanism 70 transmits a drive force generated in accordance with the rotation of the main shaft 41 to the needle bar crank link 72. The needle bar crank link 72 is driven in conjunction with the thread take-up lever 61 to move the needle bar 71 up and down.

The lower shaft 21 extends in the front-rear direction in the housing unit 2 and has a pulley 22 at its rear end. The main shaft 41 has a pulley 42 at a position corresponding to the pulley 22. The pulley 42 and the pulley 22 are connected by a timing belt 31. The sewing machine motor 32 rotates the main shaft 41, and the lower shaft 21 is rotated clockwise in the main view by the timing belt 31.

The cloth feeding device 50 includes a cloth feeding plate 51, a driving mechanism 52, a presser foot 53, a presser arm 54, a motor 55, and the like. The cloth feeding plate 51 is long in the front-rear direction and has a rectangular frame shape in plan view. The cloth feeding plate 51 is slidably disposed on the upper surface of the base unit 2, and the cloth feeding plate 51 is connected to the driving mechanism 52. The presser foot 53 is disposed above the cloth feeding plate 51. A presser foot 53 is fixed to a front end portion of the presser arm 54, and a rear end portion of the presser arm 54 is connected to the drive mechanism 52. The presser foot 53 moves downward with the cloth placed on the upper surface of the cloth feeding plate 51, and sandwiches the cloth between the presser foot and the cloth feeding plate 51. The drive mechanism 52 is provided inside the base unit 2, and the drive mechanism 52 moves the presser foot 53 and the cloth feeding plate 51 in the front-rear direction using the motor 55 as a drive source.

The shuttle mechanism is connected to the front end of the lower shaft 21. The shuttle mechanism has a vertical shuttle which is rotated by being driven by the lower shaft 21. The vertical shuttle is provided with a bobbin case. The bobbin case accommodates a bobbin around which a bobbin thread is wound. A needle plate is provided on the upper part of the bed unit 2. The vertical shuttle is positioned below the needle plate. The needle bar 71 is above the needle board. When the needle bar 71 descends, the lower end of the needle reaches the upper part of the vertical shuttle via a needle accommodating hole formed in the needle plate. The vertical hook and the needle bar 71 cooperate to interlace the lower thread drawn from the bobbin case with the upper thread held by the needle. The thread take-up lever 61 pulls the upper thread interwoven with the lower thread onto the needle plate. The sewing machine 1 performs sewing while moving a cloth clamped between the presser foot 53 and the cloth feeding plate 51, thereby forming a keyhole stitch P (see fig. 2) in the cloth W.

Referring to fig. 2 and 3, the cloth cutting apparatus 100 is illustrated. The cloth cutting apparatus 100 is an apparatus that: the center of the keyhole stitch P is cut by the cutter 170 to form a straight buttonhole H (see fig. 5). The cloth cutting apparatus 100 is provided at the tip portion 5. The cloth cutting apparatus 100 includes a motor 110, a rotary arm 120, a connecting arm 130, a guide member 140, a working shaft 150, a holding member 160, and a cutter 170.

The motor 110 is a pulse motor, which is a driving source of the cloth cutting apparatus 100. The motor 110 is fixed to the frame of the sewing machine 1 via a fixing member 115 at an upper portion of the arm portion 4. The fixing member 115 has a portion 116 extending in the horizontal direction and a portion 117 extending downward from the front end of the portion 116. In the fixing member 115, a portion 116 is fixed to a frame of the sewing machine 1, and a motor 110 is fixed to a rear side of the portion 117. An output shaft 111 of the motor 110 extends forward, and the output shaft 111 is connected to the rotating arm 120 at a front side of the fixing member 115. The rotating arm 120 has a base portion 121, an eccentric portion 122, and an engaging pin 123. The base portion 121 is fixed to the output shaft 111 of the motor 110 by fastening screws. The eccentric portion 122 extends from the base portion 121 in the radial direction, and is eccentric with respect to the axial center of the output shaft 111. The engagement pin 123 is provided on the eccentric portion 122. The engagement pin 123 has a cylindrical shape and protrudes forward from the eccentric portion 122. When the output shaft 111 of the motor 110 rotates, the engagement pin 123 revolves around the output shaft 111. The engagement pin 123 engages with the engagement groove 135 of the connection arm 130, and the engagement pin 123 moves the operating shaft 150 up and down via the connection arm 130. The engagement pin 123 and the engagement groove 135 are a conversion mechanism 180 that converts the direction of the driving force and transmits the driving force.

The coupling arm 130 extends in the up-down direction and the front-rear direction, and couples the rotation arm 120 and the operation shaft 150. The connecting arm 130 has a lower end 131, a body 132, a shaft fixing portion 133, a block holding portion 134, and an engaging groove 135. The lower end 131 extends in the front-rear direction, and has a shaft fixing portion 133 at its front end and a block holding portion 134 at its rear end. The shaft fixing portion 133 has a shaft hole penetrating in the vertical direction. The working shaft 150 is inserted through the shaft hole and fixed to the shaft fixing portion 133 by a screw 139. The guide block 144 is assembled to the block holding portion 134. The guide block 144 engages with a guide groove 143 described later. The body 132 extends rearward and upward from the lower end 131 and has an engagement groove 135 at its upper end. The engaging groove 135 has a vertical plate 136, an upper plate 137, and a lower plate 138. The vertical plate 136 extends in the up-down direction and the left-right direction, and the vertical plate 136 is connected to the upper end of the main body 132. The upper plate 137 horizontally protrudes rearward from the upper side of the vertical plate 136. The lower plate 138 horizontally protrudes rearward from the lower edge of the vertical plate 136. The upper plate 137 and the lower plate 138 extend in the left-right direction and face each other in the vertical direction, and the upper plate 137 and the lower plate 138 are spaced apart from each other by a distance substantially equal to the outer diameter of the engagement pin 123. The engagement pin 123 is movable left and right in the engagement groove 135, and the engagement pin 123 abuts against the upper plate 137 or the lower plate 138 when moving up and down. Therefore, the conversion mechanism 180 transmits the vertical component of the rotational driving force generated by the rotation of the output shaft 111 of the motor 110 to the connection arm 130, but does not transmit the horizontal component to the connection arm 130.

The guide member 140 guides the up-and-down movement of the link arm 130. The guide member 140 has a fixing portion 141 and a guide portion 142, and the fixing portion 141 and the guide portion 142 together form a plate shape that is bent at a substantially right angle. The fixing portion 141 is a portion: at this position, the guide member 140 can be fixed to the frame of the sewing machine 1 by four screws 146. The guide portion 142 extends rightward from the rear end of the fixing portion 141, and a guide groove 143 is formed on the front surface of the guide portion 142. The guide groove 143 extends in the vertical direction. A substantially square guide block 144 is engaged with the guide groove 143, and the guide block 144 is slidable in the groove. The guide block 144 has a pin 145 having a cylindrical shape. The pin 145 protrudes forward, and the pin 145 is fitted into a circular hole provided in the rear surface of the block holding portion 134 of the coupling arm 130. The pin 145 absorbs positional deviation in the front-rear direction between the coupling arm 130 and the guide member 140 and inclination of the guide block 144 with respect to the guide groove 143. Therefore, the pin 145 ensures smooth movement of the guide block 144 in the guide groove 143.

The working shaft 150 is a metal rod extending in the vertical direction and having a cylindrical shape. The operating shaft 150 is disposed on the left of the main shaft 41 and behind the needle bar 71 in the distal end portion 5. The intermediate portion of the operating shaft 150 is fixed to the shaft fixing portion 133 of the coupling arm 130 by a screw 139. The lower portion of the operating shaft 150 is inserted into the support cylinder 151. The support cylinder 151 is fixed to a frame of the sewing machine 1. The support cylinder 151 supports a lower portion of the working shaft 150 and guides the vertical movement of the working shaft 150. The lower end of the operating shaft 150 is exposed from below the tip end portion 5 and extends downward. The holding member 160 is fixed to the lower end of the working shaft 150.

The holding member 160 is a plate-like member extending rightward and forward, and a left rear portion thereof is connected to a lower end of the operating shaft 150. The holding member 160 transmits the power of the working shaft 150 moving up and down to the cutter 170. The holding member 160 has a bracket 161 at the lower right front portion. The bracket 161 extends forward and downward. The cutter 170 is fixed to the lower end of the holder 161 by a screw 162 with its blade facing downward. The cutter 170 extends in the front-rear direction with the blade at the rear side. The cutter 170 is located behind the needle.

Referring to fig. 2 to 5, the operation of the cloth cutting apparatus 100 will be described. When the cloth cutting apparatus 100 is not in operation, the motor 110 stops the output shaft 111 in an excited state. At this time, the engagement pin 123 of the rotation arm 120 is positioned above the output shaft 111. After the keyhole stitch P is sewn, the sewing machine 1 drives the cloth feeding device 50 to move the cloth W. At this time, the center of the keyhole stitch P is positioned right under the cutter 170. When the cloth cutting apparatus 100 is operated, the sewing machine 1 drives the motor 110 to rotate the output shaft 111 360 degrees counterclockwise in the front view. At this time, the sewing machine 1 may rotate the output shaft 111 360 degrees clockwise in the front view. The sewing machine 1 may be configured such that the output shaft 111 is rotated 180 degrees in the clockwise direction in the main view and then rotated 180 degrees in the counterclockwise direction in the main view.

In fig. 4, the rotation arm 120 and the engagement groove 135 during the non-operation are shown by solid lines, and the initial position of the output shaft 111 during the non-operation is set to 0 degree. As shown in fig. 4, when the output shaft 111 rotates counterclockwise from 0 degree to 90 degrees, the engagement pin 123 rotates in an arc from the upward direction of the output shaft 111 to the left as indicated by an arrow R1. The direction in which the engagement pin 123 moves by the rotation of the output shaft 111 has a component of the direction toward the left and a component of the direction toward the lower. As shown by the chain line, the lower portion of the outer peripheral surface of the engagement pin 123 pushes the lower plate 138 of the engagement groove 135 downward, and the engagement pin 123 moves leftward in the engagement groove 135, so that the engagement pin 123 and the engagement groove 135 do not abut against each other in the horizontal direction. Therefore, the conversion mechanism 180 does not transmit the component of the direction toward the left among the components of the direction of the driving force generated by the driving of the motor 110. The engaging groove 135 receives a downward pushing force from the engaging pin 123, and moves the connecting arm 130 downward as indicated by an arrow M1. At this time, the guide groove 143 of the guide member 140 guides the downward movement of the guide block 144 assembled to the block holding portion 134 of the coupling arm 130. Since the conversion mechanism 180 does not transmit the horizontal component of the driving force, the guide block 144 does not apply a horizontal thrust to the guide groove 143. When the working shaft 150 moves downward by the connecting arm 130, the cutter 170 descends and approaches the center of the keyhole stitch P of the cloth W.

When the output shaft 111 rotates counterclockwise from 90 degrees to 180 degrees, the engagement pin 123 rotates in an arc downward from the left side of the output shaft 111 as indicated by an arrow R2. The direction in which the engagement pin 123 moves by the rotation of the output shaft 111 has a component of the direction toward the right and a component of the direction toward the lower side. As shown by the two-dot chain line, the lower portion of the outer peripheral surface of the engagement pin 123 pushes the lower plate 138 of the engagement groove 135 downward, and the engagement pin 123 moves rightward in the engagement groove 135, so that the engagement pin 123 and the engagement groove 135 do not abut against each other in the horizontal direction. Therefore, the conversion mechanism 180 does not transmit the component of the direction of the driving force generated by the driving of the motor 110, which is directed to the right. The engaging groove 135 receives a downward pushing force from the engaging pin 123, and moves the connecting arm 130 further downward as indicated by an arrow M2. At this time, the guide groove 143 of the guide member 140 guides the downward movement of the guide block 144. Since the conversion mechanism 180 does not transmit the horizontal component of the driving force, the guide block 144 of the coupling arm 130 does not apply a horizontal thrust to the guide groove 143 of the guide member 140. When the working shaft 150 moves downward via the connecting arm 130, as shown in fig. 5, the cutter 170 further descends to cut the cloth W at the center of the keyhole stitch P of the cloth W, thereby forming a keyhole H in the cloth W.

As shown in fig. 4, when the output shaft 111 rotates from 180 degrees to 270 degrees in the counterclockwise direction, the engagement pin 123 rotates in an arc from the lower side of the output shaft 111 to the right as indicated by an arrow R3. The direction in which the engagement pin 123 moves by the rotation of the output shaft 111 has a component of the direction toward the right and a component of the direction toward the upper. As shown by the chain line, the engaging pin 123 pushes the upper plate 137 of the engaging groove 135 upward by the upper portion of the outer peripheral surface thereof, and the engaging pin 123 moves rightward in the engaging groove 135, so that the engaging pin 123 and the engaging groove 135 do not abut on each other in the horizontal direction. Therefore, the conversion mechanism 180 does not transmit the component of the direction of the driving force generated by the driving of the motor 110, which is directed to the right. The engagement groove 135 receives an upward urging force from the engagement pin 123, and moves the coupling arm 130 upward as indicated by an arrow M3. At this time, the guide groove 143 of the guide member 140 guides the upward movement of the guide block 144. Since the conversion mechanism 180 does not transmit the horizontal component of the driving force, the guide block 144 of the coupling arm 130 does not apply a horizontal thrust to the guide groove 143 of the guide member 140. When the working shaft 150 moves upward via the connecting arm 130, the cutter 170 is raised and moves upward of the cloth W.

When the output shaft 111 rotates counterclockwise from 270 degrees to 360 degrees, the engagement pin 123 rotates in an arc upward from the right of the output shaft 111 as indicated by an arrow R4. The direction in which the engagement pin 123 moves by the rotation of the output shaft 111 has a component of the direction toward the left and a component of the direction toward the top. As shown by the solid line, the engaging pin 123 pushes the upper plate 137 of the engaging groove 135 upward by the upper portion of the outer peripheral surface thereof, and the engaging pin 123 moves leftward in the engaging groove 135, so that the engaging pin 123 and the engaging groove 135 do not abut in the horizontal direction. Therefore, the conversion mechanism 180 does not transmit the component of the direction toward the left among the components of the direction of the driving force generated by the driving of the motor 110. The engagement groove 135 receives an upward urging force from the engagement pin 123, and moves the coupling arm 130 further upward as indicated by an arrow M4. At this time, the guide groove 143 of the guide member 140 guides the upward movement of the guide block 144. Since the conversion mechanism 180 does not transmit the horizontal component of the driving force, the guide block 144 of the coupling arm 130 does not apply a horizontal thrust to the guide groove 143 of the guide member 140. When the operating shaft 150 moves upward via the connecting arm 130, the cutter 170 further moves upward and moves to the initial position during non-operation. The motor 110 stops the output shaft 111 in an excited state.

As described above, the direction of the driving force generated by the rotation of the output shaft 111 of the motor 110 includes the vertical component and the horizontal component. Since the engagement groove 135 of the conversion mechanism 180 extends in the horizontal direction, the engagement groove 135 and the engagement pin 123 vertically abut against each other, and do not horizontally contact each other. Therefore, the conversion mechanism 180 transmits the vertical component of the driving force, but does not transmit the horizontal component. The connecting arm 130 does not move in the horizontal direction, and does not generate horizontal resistance to the guide groove 143 of the block holding portion 134 that guides the connecting arm 130 in the vertical direction. Therefore, the cloth cutting apparatus 100 can prevent the guide groove 143 from being worn or deformed, and the work shaft 150 is less likely to be horizontally moved even after a long time use. The cloth cutting apparatus 100 can maintain the stable cutting of the cloth W by the cutter 170 for a long period of time.

The eccentric portion 122 of the rotating arm 120 rotates together with the output shaft 111 of the motor 110. The engagement pin 123 revolves around the output shaft 111, and the engagement pin 123 vertically abuts against the engagement groove 135. The engaging pin 123 protrudes from the eccentric portion 122. Therefore, even if the contact position of the engagement pin 123 with the engagement groove 135 changes during the revolution, the engagement pin 123 can be maintained in contact with the engagement groove 135 in the vertical direction. Since the engagement pin 123 and the engagement groove 135 vertically contact each other, the conversion mechanism 180 transmits the vertical component of the driving force. Since the engagement pin 123 moves in the horizontal direction with respect to the engagement groove 135, the engagement pin 123 does not come into contact with the engagement groove 135 in the horizontal direction, and therefore, the horizontal direction component of the driving force is not transmitted to the conversion mechanism 180. The cloth cutting apparatus 100 can prevent the guide groove 143 from being worn, deformed, and the like.

The engagement pin 123 protrudes from the eccentric portion 122 in parallel with the output shaft 111, and the engagement pin 123 is parallel with both the surface of the upper plate 137 and the surface of the lower plate 138 of the engagement groove 135. Therefore, the engagement pin 123 can be brought into contact with the engagement groove 135 at a position between the protruding root portion and the tip end, and the driving force can be efficiently transmitted to the engagement groove 135.

In the connecting arm 130, a shaft fixing portion 133 connected to the operating shaft 150 is provided at the front end of the lower end portion 131, and a block holding portion 134 is provided at the rear end of the lower end portion 131, which is the opposite side of the lower end portion 131 from the shaft fixing portion 133, and a guide block 144 engaged with the guide groove 143 of the guide member 140 is assembled to the block holding portion 134. Therefore, the coupling arm 130 can be disposed close to the operating shaft 150, and the driving force generated by the driving of the motor 110 can be efficiently transmitted to the operating shaft 150.

The present invention can be modified in various ways in addition to the above embodiments. The direction in which the holding member 160 extends may be set as appropriate according to the position of the operating shaft 150 disposed in the distal end portion 5 of the sewing machine 1. The retaining member 160 may not be present. In this case, the cutter 170 may be attached to the lower end of the working shaft 150 via the holder 161. The direction in which the body 132 extends may be a vertical direction or a horizontal direction. The engagement pin 123 may be provided so as to be rotatable with respect to the eccentric portion 122 of the rotation arm 120, or may be provided so as not to be rotatable with respect to the eccentric portion 122. The guide block 144 may not be present. In this case, for example, a pin may be fixed to the block holding portion 134, and the connection arm 130 may be engaged with the guide groove 143 via the pin.

The cloth cutting apparatus 200 in fig. 6 is an example in which a square slider 225 is connected to the tip end portion of the engagement pin 223 of the rotary arm 220. The circle U1 represents the switching mechanism 280 when viewed from a primary viewing angle, cut along line ii-ii. The rotating arm 220 has an eccentric portion 222, an engaging pin 223, and a square slider 225. The eccentric portion 222 has substantially the same structure as the eccentric portion 122 of the above embodiment. The square slider 225 has a hole 226 into which the tip end portion of the engagement pin 223 is inserted, and is fixed to the engagement pin 223 by a fastening screw. The rear end of the engagement pin 223 is inserted into the hole 224 provided in the eccentric portion 222, and the engagement pin 223 is rotatable with respect to the eccentric portion 222. The square slider 225 is engaged with the engaging groove 235 of the connecting arm 230, and the square slider can slide in the left-right direction. The coupling arm 230 has substantially the same structure as the coupling arm 130 of the above embodiment. The square slider 225 and the engaging groove 235 are a switching mechanism 280 for switching the direction of the driving force and transmitting the driving force. As described in the above embodiment, the square slider 225 and the engagement groove 235 contact each other in a planar manner, and the area of contact with the engagement groove 235 can be increased as compared with the case where the engagement pin 123 and the engagement groove 135 contact each other in a linear manner. Therefore, the engagement pin 223 can transmit the driving force to the engagement groove 235 more efficiently.

The cloth cutting apparatus 300 in fig. 7 is an example in which a cylindrical rolling member 325 is disposed around the engagement pin 323 at the engagement pin 323. Shown in circle U2 is a shifter mechanism 380 when viewed from a primary perspective after sectioning along line iii-iii. The rotating arm 320 has an eccentric portion 322, an engagement pin 323, and a rolling member 325. The eccentric portion 322 has substantially the same structure as the eccentric portion 122 of the above embodiment. The engagement pin 323 is inserted into the rolling member 325, and the rear end of the engagement pin 323 is inserted into the hole 324 provided in the eccentric portion 322 of the rotating arm 320. The rolling member 325 is rotatable with respect to the engagement pin 323. The engagement pin 323 engages with the engagement groove 335 of the connection arm 330 via the rolling member 325. When the engagement pin 323 moves in the left-right direction, the rolling member 325 rotates, and therefore, the engagement pin 323 does not slide with respect to the engagement groove 335. The structure of the connecting arm 330 is substantially the same as that of the connecting arm 130 of the above embodiment. The rolling member 325 and the engagement groove 335 are a switching mechanism 380 that switches the direction of the driving force and transmits the driving force. As described in the above embodiment, the abrasion of the engagement pin 323 can be suppressed as compared with the case where the engagement pin 123 slides with respect to the engagement groove 135, and therefore, the engagement pin 323 can efficiently transmit the driving force to the engagement groove 335 for a long period of time.

The cloth cutting apparatus 400 of fig. 8 is an example in which an eccentric 420 is used instead of the rotary arm 120 of the above embodiment. Shown in circle U3 is shifter 480 when viewed at a primary viewing angle, cut along line IV-IV. The eccentric 420 is connected to the output shaft 111 of the motor 110. In this case, the axial center Q1 of the eccentric wheel 420 is eccentric with respect to the axial center Q2 of the output shaft 111. The outer peripheral surface 421 of the eccentric wheel 420 abuts against the engaging groove 435. The eccentric 420 rotates together with the output shaft 111 of the motor 110. The eccentric wheel 420 and the engagement groove 435 are a switching mechanism 480 that switches the direction of the driving force and transmits the driving force. The coupling arm 430 has substantially the same structure as the coupling arm 130 of the above embodiment except that it has an engagement groove 435 instead of the engagement groove 135. Since the outer peripheral surface 421 and the engagement groove 435 vertically contact each other, the conversion mechanism 480 transmits the vertical component of the driving force. Since the outer peripheral surface 421 does not abut against the engagement groove 435 in the horizontal direction, the conversion mechanism 480 does not transmit the horizontal component of the driving force. Therefore, the cloth cutting apparatus 400 can prevent the abrasion, deformation, and the like of the guide groove 143. The conversion mechanism 480 can make the eccentric portion 122 of the above embodiment a simpler structure such as only the eccentric wheel 420.

The cloth cutting apparatus 500 in fig. 9 is an example in which the conversion mechanism 580 is provided above the work shaft 150. The coupling arm 530 has a lower end 531, a body 532, a shaft fixing portion 533, a block holding portion 534, and an engagement groove 535. The connecting arm 530 has a body 532 arranged in the vertical direction, an engaging groove 535 provided at the upper end of the connecting arm 530, a shaft fixing portion 533 provided at the lower portion of the lower end 531, and a block holding portion 534 provided at the rear portion of the lower end 531. The switching mechanism 580 has the same structure as the switching mechanism 180 of the above embodiment except that it has an engagement groove 535 instead of the engagement groove 135 of the above embodiment. Rotating arm 120 may also be rotating arm 220 or rotating arm 320. Since the conversion mechanism 580 is provided above the working shaft 150, the motor 110 can be disposed closer to the working shaft 150 in the front-rear direction by using the cloth cutting apparatus 500, and further downsizing can be achieved.

The cloth cutting apparatus 600 in fig. 10 is an example in which the eccentric portion 622 of the rotating arm 620 is provided with an engaging groove 625, and the upper end of the connecting arm 630 is provided with an engaging base 635. The engagement groove 625 and the engagement base 635 are a switching mechanism 680 that switches the direction of the driving force and transmits the driving force. Shown in circle U4 is shift mechanism 680 when viewed from a primary viewing angle, cut along line v-v. The rotating arm 620 has an eccentric portion 622, a pin 623, and an engagement groove 625. The eccentric portion 622 is substantially the same in structure as the eccentric portion 122 of the above embodiment. The engaging groove 625 has a vertical plate 626, an upper plate 627 and a lower plate 628. The vertical plate 626 extends in the up-down direction and the left-right direction, and is fixed to the front end portion of the pin 623 extending in the front-rear direction. The rear end of the pin 623 is inserted into the hole 624 provided in the eccentric portion 622, and the pin 623 is rotatable with respect to the eccentric portion 622. The upper plate 627 protrudes horizontally from the upper edge of the vertical plate 626 toward the front. The lower plate 628 horizontally protrudes forward from the lower edge of the vertical plate 626. The upper plate 627 and the lower plate 628 each extend in the left-right direction and oppose each other in the up-down direction, and the upper plate 627 and the lower plate 628 are spaced apart from each other by a distance substantially equal to the up-down direction width of the engaging protrusion 636 of the engaging base 635. The coupling arm 630 has substantially the same structure as the coupling arm 130 of the above embodiment except that it has an engagement base 635 instead of the engagement groove 135. The engagement base 635 is located at the upper end of the connection arm 630 and has a substantially rectangular parallelepiped shape. The engaging protrusion 636 extends in the left-right direction on the rear surface of the engaging base 635 and protrudes rearward. The engagement groove 625 engages with the engagement protrusion 636, and the engagement groove 625 can slide in the left-right direction.

The eccentric portion 622 rotates together with the output shaft 111 of the motor 110. The engagement groove 625 revolves around the output shaft 111. The engaging protrusion 636 extends parallel to the engaging groove 625, and the engaging protrusion 636 vertically abuts against the engaging groove 625. Since the engagement groove 625 is rotatable with respect to the rotation arm 620, even if the engagement groove 625 revolves around the output shaft 111, the orientation of the engagement groove 625 can be corrected by the engagement projection 636, and the orientation of the groove in the horizontal direction can be maintained. Since the engagement groove 625 and the engagement projection 636 are in contact with each other in the vertical direction, the conversion mechanism 680 transmits the vertical component of the driving force. Since the engagement groove 625 moves in the horizontal direction with respect to the engagement protrusion 636, the conversion mechanism 680 does not transmit the horizontal component of the driving force. Therefore, the cloth cutting apparatus 600 can prevent the abrasion, deformation, and the like of the guide groove 143.

The cloth cutting apparatus 700 in fig. 11 is an example in which the guide groove 743 of the guide member 740 is disposed on the front side of the coupling arm 730. The guide member 740 is fixed to a frame of the sewing machine 1. The shaft fixing portion 733 is provided at the tip of the lower end portion 731 of the connecting arm 730 together with the block holding portion 734. The shaft fixing portion 733 is a portion for fixing the working shaft 150. The guide block 744 is assembled to the block holding portion 734, and the guide block 744 is engaged with the guide groove 743 of the guide member 740. The guide block 744 is substantially the same in structure as the guide block 144 of the above embodiment. The block holding portion 734 is provided at the tip of the lower end portion 731 of the connecting arm 730 on the same side as the shaft fixing portion 733. The structure of shifter 780 can also be the same as shifter 180. Rotating arm 120 may also be rotating arm 220 or rotating arm 320. The switching mechanism 780 transmits the vertical component of the driving force, but does not transmit the horizontal component. Therefore, even when the block holding portion 734 is provided on the same side as the shaft fixing portion 733, the cloth cutting apparatus 700 can prevent wear, deformation, and the like of the guide groove 743.

The cloth cutting apparatus 800 in fig. 12 is an example in which a guide member 890 is provided on the upper portion of the connecting arm 830 in addition to the guide member 140. The guide member 890 guides the up-and-down movement of the link arm 830. The guide member 890 is fixed to the fixing member 815. The fixing member 815 has a portion 816 extending in the horizontal direction, a portion 817 extending downward from the front end of the portion 816, and a portion 818 extending forward from the left end of the portion 817. In the fixing member 815, a portion 816 is fixed to a frame of the sewing machine 1, a motor 110 is fixed to a rear side of the portion 817, and a guide member 890 is fixed to the portion 818. An engagement groove 835 and a block holding portion 839 are provided at the upper end of the coupling arm 830. The engagement groove 835 has substantially the same structure as the engagement groove 135 of the above embodiment. The guide piece 894 is assembled to the piece holding portion 839, and the guide piece 894 engages with the guide groove 893 of the guide member 890. The block holding portion 839 is provided at the upper left end of the engagement groove 835, and the guide block 894 is provided to the left of the block holding portion 839. The guide groove 893 is disposed on the left side of the connecting arm 830 and extends in the vertical direction. The switching mechanism 880 has the same configuration as the switching mechanism 180 of the above embodiment, except that an engagement groove 835 is provided instead of the engagement groove 135 of the above embodiment. Rotating arm 120 may also be rotating arm 220 or rotating arm 320.

The holding member 160 holds the cutter 170 at the right side of the lower end portion of the working shaft 150. When the cutting blade 170 comes into contact with the fabric W at the time of cutting the fabric W, and then the connecting arm 830 further moves the operating shaft 150 downward, the operating shaft 150 is inclined leftward with the cutting blade 170 as a fulcrum. The guide groove 893 provided on the left side of the upper end of the connecting arm 830 is on the side where the operating shaft 150 is inclined. Therefore, the guide groove 893 suppresses the inclination of the operating shaft 150 on the upper end side of the coupling arm 830 against the action of the operating shaft 150. Therefore, the horizontal direction stress is not applied to the cutter 170.

In the above-mentioned embodiment and modified example, motor 110 corresponds to the utility model discloses a motor, connection arm 130, connection arm 230, connection arm 430, connection arm 630, connection arm 830 correspond to the utility model discloses an arm, cloth W correspond to the utility model discloses a cloth, retaining member 160 correspond to the utility model discloses a retaining part, clamping groove 135, clamping groove 625 correspond to the utility model discloses a slot portion, clamping pin 123, the protruding 636 of block correspond to the utility model discloses a clamping part, guiding groove 143 correspond to the utility model discloses a other end guide portion, guiding groove 893 correspond to the utility model discloses an one end guide portion, keyhole stitch P correspond to the utility model discloses a stitch, keyhole H correspond to the utility model discloses a cut hole.

Claims (11)

1. A cloth cutting apparatus (100, 200, 400, 600, 800) comprising:

a motor (110) as a drive source;

an eccentric section (122) connected to an output shaft (111) of the motor, the eccentric section being eccentric with respect to the axis of the output shaft;

an arm (130, 230, 430, 630, 830) having one end connected to the eccentric portion, the arm transmitting a driving force of the motor;

a working shaft (150) connected to the other end of the arm, the working shaft operating a cutter (170) for cutting a cloth (W); and

a holding part (160) which is arranged at the lower end part of the working shaft and is used for holding the cutting knife,

it is characterized in that the preparation method is characterized in that,

the cloth cutting device is provided with a conversion mechanism (180) which is positioned between the eccentric part and the one end part of the arm part and converts the rotation of the output shaft of the motor into the up-and-down motion of the working shaft,

the conversion mechanism includes:

a groove (135, 625) extending in the horizontal direction;

an engaging portion (123, 636) that engages with the groove portion; and

a second end guide (143) that guides the second end of the arm in the vertical direction,

one of the groove portion and the engaging portion is provided in the eccentric portion, and the other of the groove portion and the engaging portion is provided in the arm portion.

2. Cloth cutting device according to claim 1,

the groove portion is provided at the one end portion of the arm portion,

the engaging portion is provided at a position of the eccentric portion eccentric with respect to an axis of the output shaft, and the engaging portion protrudes toward the groove portion.

3. Cloth cutting device according to claim 2,

the engaging portion protrudes in parallel to the output shaft in the eccentric portion.

4. Cloth cutting device according to claim 2,

the cloth cutting device is provided with a square sliding block (225), the square sliding block is arranged on the clamping part and can rotate relative to the eccentric part, and the square sliding block is clamped with the groove part and can move along the horizontal direction.

5. Cloth cutting device according to claim 3,

the cloth cutting device is provided with a square sliding block, the square sliding block is arranged on the clamping part and can rotate relative to the eccentric part, and the square sliding block is clamped with the groove part and can move along the horizontal direction.

6. Cloth cutting device according to claim 1,

the eccentric is an eccentric (420) such that: which is fixed to the output shaft of the motor and whose axis is eccentric with respect to the axis of the output shaft,

the groove portion is provided at the one end portion of the arm portion, and the engaging portion is the eccentric wheel.

7. Cloth cutting device according to claim 1,

the groove portion is provided in the eccentric portion so as to be rotatable with respect to the eccentric portion,

the engaging portion is provided at the one end portion of the arm portion, protrudes toward the groove portion, and extends in parallel with the groove portion.

8. The cloth cutting apparatus according to any one of claims 1 to 7,

the other end guide portion is provided on a side of the other end portion of the arm portion opposite to a side where the connecting portion of the working shaft is located.

9. The cloth cutting apparatus according to any one of claims 1 to 7,

the cloth cutting device has one end guide portion (893) which guides the one end portion of the arm portion in the up-down direction,

the holding part holds the cutter at a position closer to one side in the horizontal direction than the position of the lower end part of the working shaft,

the one end guide portion is provided on the other side in the horizontal direction with respect to the one end portion of the arm portion.

10. Cloth cutting device according to claim 8,

the cloth cutting device has one end guide portion which guides the one end portion of the arm portion in an up-down direction,

the holding part holds the cutter at a position closer to one side in the horizontal direction than the position of the lower end part of the working shaft,

the one end guide portion is provided on the other side in the horizontal direction with respect to the one end portion of the arm portion.

11. A sewing machine is characterized in that a sewing machine body,

the sewing machine (1) comprises:

a cloth feeding device (50) for feeding cloth in a horizontal direction;

a needle bar (71) equipped with a needle at a lower end thereof, the needle bar being capable of moving up and down; and

the cloth cutting apparatus as claimed in any one of claims 1 to 10,

the cloth feeding device feeds the cloth in cooperation with the up-and-down movement of the needle bar, forms a stitch (P) on the cloth, and cuts the cloth using the cutter driven by the cloth cutting device, thereby forming a cut hole (H) corresponding to the stitch.

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