CN111926471A

CN111926471A - Needle feed sewing machine

Info

Publication number: CN111926471A
Application number: CN201910394894.XA
Authority: CN
Inventors: 李瑛�; 曹根
Original assignee: Juki Corp
Current assignee: Juki Corp
Priority date: 2019-05-13
Filing date: 2019-05-13
Publication date: 2020-11-13
Anticipated expiration: 2039-05-13
Also published as: CN111926471B

Abstract

The invention provides a needle feeding sewing machine, which restrains the variation of phase and adjusts the height of feeding teeth. A needle feed sewing machine (10) comprises: a sewing machine motor (13); a lower shaft (15) which is driven by the sewing machine motor to rotate; a vertical feed mechanism (40) which gives vertical reciprocating motion to the feed teeth (4); and a horizontal feeding mechanism (60) which gives reciprocating back and forth motion to the feeding teeth along the feeding direction of the sewed object, in the needle feeding sewing machine (10), the vertical feeding mechanism comprises: an up-and-down feed shaft (41) that performs reciprocating rotational motion; an upper and lower crank mechanism (44) for transmitting reciprocating rotational motion from the lower shaft to the upper and lower feed shafts; an upper and lower feed arm (42) fixedly connected to the upper and lower feed shafts and oscillating reciprocally together with the upper and lower feed shafts; and a height adjusting part (50) which adjusts the height of the feeding teeth through the angle adjustment of the upper and lower feeding wrists relative to the upper and lower feeding shafts.

Description

Needle feed sewing machine

Technical Field

The present invention relates to a needle feed sewing machine that feeds a workpiece by feed teeth.

Background

Conventionally, a sewing machine uses a sewing machine motor as a drive source, and a vertical feed mechanism imparts reciprocating motion in the vertical direction to feed teeth, and a horizontal feed mechanism imparts reciprocating forward and backward motion in the horizontal direction (feed direction) to the feed teeth, thereby performing feed motion of a workpiece on a needle plate.

The vertical feeding mechanism comprises: an up-down feed cam, which is an eccentric cam arranged on a lower shaft that rotates in a whole circle through a sewing machine motor; and a crank lever having one end supported by the vertical feed cam and the other end connected to one end of a feed table that holds the feed teeth (see, for example, patent document 1).

An eccentric shaft is provided at a connecting portion between the crank lever and the feed table, and the height of the feed dog is adjusted when the eccentric shaft is rotated and moved up and down.

Patent document 1: japanese patent laid-open publication No. 2018-149248

However, the conventional sewing machine described above has a problem that if the height of the feed teeth is adjusted by the eccentric shaft, the phase is also changed together with the change in the height of the feed teeth.

That is, if the eccentric shaft is rotated, the crank lever is swung about the vertical feed cam together with the fluctuation in the height of the feed dog, and this swing becomes a cause of fluctuation in the phase of vertical movement of the feed dog relative to the phase of vertical movement of the needle.

Therefore, when the height of the feed teeth is adjusted, the phases of the feed teeth must be adjusted simultaneously, which makes the height adjustment work complicated.

Disclosure of Invention

The present invention is intended to suppress phase fluctuation during height adjustment of feed teeth, and has any of the following characteristics (1) to (4).

(1)

A needle feed sewing machine having:

a sewing machine motor;

a lower shaft rotationally driven by the sewing machine motor;

an up-down feeding mechanism for providing reciprocating motion in the up-down direction to the feeding teeth; and

a horizontal feeding mechanism for providing reciprocating back and forth motion along the feeding direction of the sewed object to the feeding teeth,

the needle feed sewing machine is characterized in that,

the horizontal feeding mechanism comprises:

a horizontal feed shaft;

a horizontal crank mechanism for transmitting reciprocating rotational motion from the lower shaft to the horizontal feed shaft; and

a horizontal feed wrist fixedly connected to the horizontal feed shaft and having a swing end connected to the feed gear,

the vertical feeding mechanism comprises:

an upper and lower feed shaft which performs reciprocating rotation;

an upper and lower crank mechanism for imparting reciprocating rotational motion to the upper and lower feed shafts from the lower shaft;

an up-down feed wrist which is fixedly connected to the up-down feed shaft and has a swing end part for reciprocating up-down movement of the feed teeth; and

and a height adjusting part for adjusting the height of the feeding teeth by adjusting the angle of the upper and lower feeding wrists relative to the upper and lower feeding shafts.

(2)

The needle feed sewing machine according to the above (1), characterized in that,

the horizontal feed shaft, the lower shaft, and the vertical feed shaft are arranged in this order from the upstream side to the downstream side in the feed direction of the material to be sewn in plan view.

(3)

The needle feed sewing machine according to the above (1) or (2), wherein,

the upper and lower crank mechanisms have: an up-down feed cam composed of an eccentric cam coupled to the lower shaft; an up-down feed lever having one end portion rotatably coupled to the up-down feed cam; and an input wrist fixedly connected to the vertical feed shaft and having a swing end connected to the other end of the vertical feed rod,

the needle feed sewing machine includes an up-down movement range adjusting section for adjusting an up-down movement range of the feed gear by adjusting a coupling position of the other end portion of the up-down feed lever and the swing end portion of the input arm along the input arm.

(4)

The needle feed sewing machine according to any one of the above (1) to (3),

the horizontal feed mechanism has a phase adjustment section that adjusts a phase of a reciprocating back and forth movement of the feed teeth in the feed direction with respect to an axial angle of the lower shaft,

the horizontal crank mechanism has: a horizontal feed cam formed of an eccentric cam coupled to the lower shaft; a horizontal feed lever having one end rotatably coupled to the horizontal feed cam; an input wrist coupled to the horizontal feed shaft; and a horizontal feed connecting link connecting the other end of the horizontal feed rod and the swing end of the input wrist,

the phase adjusting section adjusts the phase of the reciprocating back-and-forth movement of the feed teeth by adjusting the angle of the horizontal feed cam with respect to the lower shaft.

(5)

The needle feed sewing machine according to the above (4), wherein,

has a feed amount adjusting mechanism for adjusting the feed distance,

the feed amount adjusting mechanism includes:

a slide body rotatably holding a coupling portion between the horizontal feed lever and the horizontal feed coupling link;

a guide portion having a guide groove and slidably supporting the slider along the guide groove;

a slider block having the guide portion; and

a feed amount adjusting motor having an output shaft connected to the slider block,

the feed distance adjusting motor is driven to rotate the slider block to change the direction of the guide groove, and the horizontal feed rod and the connecting portion of the horizontal feed connecting link are moved in different directions to adjust the feed distance.

ADVANTAGEOUS EFFECTS OF INVENTION

As described above, according to the needle feed sewing machine of the present invention, the phase variation at the time of adjusting the height of the feed dog can be suppressed.

Drawings

Fig. 1 is a perspective view of a needle feed sewing machine according to an embodiment of the present invention, in which a structure related to needle feed and feed of a workpiece is extracted.

Fig. 2 is an oblique view of the up-down feeding mechanism.

Fig. 3 is an oblique view of the horizontal feed mechanism.

Fig. 4 is an exploded perspective view of the horizontal feed mechanism and the feed amount adjustment mechanism.

Fig. 5 is a perspective view showing a state in which the horizontal feed wrist and the feed table are coupled to each other by the horizontal feed eccentric pin.

Fig. 6 is an oblique view of the horizontal feeding eccentric pin.

Fig. 7 is a perspective view of an up-down feeding mechanism as a comparative example.

Fig. 8 is a diagram showing a movement locus of the feed teeth in a case where the height adjustment of the feed teeth is performed by the height adjustment unit of the vertical feed mechanism as the embodiment.

Fig. 9 is a diagram showing a movement locus of the feed teeth in the case where the height adjustment of the feed teeth is performed by the adjustment pin of the vertical feed mechanism as a comparative example.

Fig. 10 is a diagram showing the movement locus of the feed teeth in the case where the vertical movement width of the feed teeth is adjusted by the vertical movement width adjusting section of the vertical feeding mechanism.

Fig. 11 is a diagram showing a movement locus of the feed teeth in a case where the phase of the reciprocating motion in the front-rear direction is adjusted by the phase adjusting section, fig. 11 (a) shows a state before the adjustment, fig. 11 (B) shows a state in which the phase is advanced by 10 °, fig. 11 (C) shows a state in which the phase is advanced by 20 °, fig. 11 (D) shows a state in which the phase is retarded by 10 °, and fig. 11 (E) shows a state in which the phase is retarded by 20 °.

Description of the reference numerals

4 feed tooth

5 feeding table

10-needle feed sewing machine

11 stitch

12-needle bar

13 Sewing machine motor

14 needle board

15 lower shaft

16 upper shaft chain wheel

17 lower shaft sprocket

18 synchronous belt

20 sewing needle up-down moving mechanism

21 Upper shaft

22-needle bar crank

23 bar holding part

24 needle bar crank rod

30-needle feeding mechanism

31 needle bar swing table

32 oscillating shaft

33 input wrist

34 output wrist

35 connecting rod

40 up-and-down feeding mechanism

41 Up-and-down feed shaft

42 up-down feeding wrist

421 screw

43 connecting rod for feeding vertically

44 up-down crank mechanism

45 up-and-down feeding cam

46 up-and-down feeding rod

47 input wrist

471 long hole

48 step screw

49 vertical movement amplitude adjusting part

50 height adjusting part

60 horizontal feeding mechanism

61 horizontal feed shaft

62 horizontal feed wrist

63 horizontal feeding connecting rod

64 horizontal crank mechanism

65 horizontal feed cam

651 screw

66 horizontal feed bar

67 input wrist

69 phase adjusting part

80 feed amount adjusting mechanism

81 sliding body

82 guide part

83 slider block

84 feed amount adjusting motor

85 rotating wrist

86 feed amount adjusting connecting rod

Detailed Description

[ overall Structure of embodiment ]

Next, an embodiment of the present invention will be described in detail with reference to fig. 1 to 11. In the present embodiment, a double needle feed sewing machine will be described as an example. The needle feed sewing machine is, for example, a sewing machine which can feed a workpiece such as a thick workpiece at a set pitch in a state where a needle penetrates the workpiece by swinging the needle of a needle bar in synchronization with feed teeth against the workpiece which is difficult to feed accurately at the set pitch due to slippage or the like occurring in a normal feed mechanism.

In the following description, a horizontal direction along a feed direction of a material to be sewn is defined as an X-axis direction (front-rear direction), a horizontal direction orthogonal to the X-axis direction is defined as a Y-axis direction (left-right direction), and a direction orthogonal to both the X-axis direction and the Y-axis direction is defined as a Z-axis direction (up-down direction). The downstream side in the feeding direction is referred to as "front", the upstream side is referred to as "rear", the left-hand side is referred to as "left", and the right-hand side is referred to as "right" in a state of facing forward.

Fig. 1 is a perspective view of a needle feed sewing machine 10 with a structure related to needle feed and feed of a workpiece. As shown in fig. 1, a needle feed sewing machine 10 (hereinafter, simply referred to as a sewing machine 10) has: a sewing machine motor 13 serving as a driving source for a sewing operation; a needle vertical movement mechanism 20 for applying vertical movement to the two needle rods 12 which individually hold the two needles 11; a needle feed mechanism 30 for swinging the two needle bars 12 in the X-axis direction; a lower shaft 15; an up-down feeding mechanism 40 for moving the feed teeth 4 up and down in the Z-axis direction; a horizontal feed mechanism 60 that reciprocates the feed teeth 4 in the X-axis direction; a feed amount adjusting mechanism 80 for adjusting the feed amount of the sewed object of each needle, namely the sewing pitch; and a needle board 14.

Although not shown, the sewing machine 10 has a structure necessary for sewing, such as a sewing machine frame, a pot mechanism, a thread take-up lever mechanism, and a thread adjusting device, and these structures are well known structures, and therefore, the description thereof is omitted.

[ Up-and-down moving mechanism of sewing needle ]

The needle vertical movement mechanism 20 includes: an upper shaft 21 to which a sewing machine motor 13 imparts rotation (continuous rotation in a certain direction) over the entire circumference; a needle crank 22 provided at one end of the upper shaft 21; a needle bar holding portion 23 for holding the two needle bars 12; and a needle bar crank lever 24 that connects the needle bar crank 22 and the needle bar holding portion 23.

Then, if the needle bar crank 22 rotates together with the upper shaft 21, the needle bar crank rod 24 converts the rotational motion into the vertical reciprocating motion and transmits the vertical reciprocating motion to the needle bar holding portion 23. Thereby, the needle bar 12 moves up and down according to the number of rotations of the sewing machine motor 13.

[ needle feed mechanism ]

The needle feed mechanism 30 includes: a needle bar swing table 31 for supporting the two needle bars 12 so as to be movable up and down; a swing shaft 32 for supporting the needle bar swing table 31 to be swingable around the Y axis; an input wrist 33 for inputting reciprocating rotational motion to the swing shaft 32; an output wrist 34 fixedly connected to an end of a horizontal feed shaft 61 of a horizontal feed mechanism 60 described later; and a connecting link 35 that connects the output wrist 34 and the input wrist 33.

The two needle bars 12 need to be swung so that the sewing needle 11 moves forward and backward in synchronization with the forward and backward movement of the feed teeth 4.

Therefore, the horizontal feed shaft 61 and the swing shaft 32 are coupled via the output wrist 34, the coupling link 35, and the input wrist 33 so that the horizontal feed shaft 61 and the swing shaft 32 of the horizontal feed mechanism 60 that imparts the reciprocating motion in the front-rear direction (X-axis direction) to the feed teeth 4 perform reciprocating rotation in synchronization.

Thereby, the needle bar swing table 31 swings in synchronization with the feed tooth 4, and the sewing needle 11 located at the tip of each needle bar 12 moves in the feed direction together with the feed tooth 4.

The needle vertical movement mechanism 20 and the needle feed mechanism 30 are disposed in a sewing machine arm and a vertical machine body of a sewing machine frame, not shown.

[ lower shaft ]

The lower shaft 15 is rotatably supported in a sewing machine bed portion of a sewing machine frame, not shown, in a state of being oriented in the Y-axis direction.

The lower shaft 15 and the upper shaft 21 rotate in an interlocking manner at a constant speed by a timing belt 18 that is stretched over an upper shaft sprocket 16 provided on the upper shaft 21 and a lower shaft sprocket 17 provided on the lower shaft 15.

The left end of the lower shaft 15 engages with a kettle mechanism, not shown, to input power to the kettle mechanism.

[ Up-and-down feed mechanism ]

Fig. 2 is an oblique view of the up-down feeding mechanism 40. The vertical feed mechanism 40 is disposed in a sewing machine bed portion not shown.

As shown in fig. 1 and 2, the vertical feed mechanism 40 includes: an up-down feed shaft 41 along the Y-axis direction, which performs reciprocating rotational motion; an up-down crank mechanism 44 for transmitting reciprocating rotation motion from the lower shaft 15 to the up-down feed shaft 41; an up-down feed wrist 42 fixedly connected to the up-down feed shaft 41 and oscillating back and forth together with the up-down feed shaft 41; and a vertical feed connecting link 43 for connecting a tip end portion of the feed table 5 holding the feed teeth 4 and a swing end portion of the vertical feed arm 42.

The up-down crank mechanism 44 further includes: an up-down feed cam 45 composed of an eccentric cam fixedly coupled to the lower shaft 15; an up-down feed lever 46 having one end portion rotatably coupled to the up-down feed cam 45; and an input wrist 47 fixedly connected to the vertical feed shaft 41 and input to be reciprocated from the vertical feed rod 46.

The vertical feed cam 45 is an outer peripheral cam having a circular outer periphery, and the vertical feed cam 45 is fixed to the lower shaft 15 while the lower shaft 15 penetrates through the eccentric position.

The vertical feed lever 46 has one end portion holding the outer periphery of the vertical feed cam 45 via a radial bearing, not shown, and the vertical feed cam 45 is rotatable with respect to the vertical feed lever 46. Therefore, if the up-down feeding cam 45 rotates together with the lower shaft 15, the one end portion of the up-down feeding lever 46 performs a circling motion around the lower shaft 15 in accordance with the eccentric amount of the up-down feeding cam 45.

On the other hand, the input wrist 47 has one end portion fixedly supported by a right end portion of the vertical feed shaft 41 in the Y-axis direction, and swings about the vertical feed shaft 41. Further, a long hole 471 is formed in the swing end of the input arm 47 in the longitudinal direction of the input arm 47 (the radial direction about the vertical feed shaft 41), and the other end of the vertical feed rod 46 is connected to be rotatable about the Y axis by a stepped screw 48 inserted through the long hole. The extending direction of the input wrist 47 and the extending direction of the other end of the up-down feed lever 46 are preferably substantially orthogonal to each other.

Thus, if one end of the vertical feed rod 46 revolves due to the rotation of the lower shaft 15, a reciprocating swing motion is input to the swing end of the input wrist 47 via the other end of the vertical feed rod 46, and the input wrist 47 and the vertical feed shaft 41 perform a reciprocating swing motion integrally at a period equal to the rotation period of the lower shaft 15.

A vertical feed arm 42 is held and fixed to a left end portion of the vertical feed shaft 41, and the vertical feed arm 42 is swingable integrally with the vertical feed shaft 41. The swing end of the vertical feed arm 42 is connected to one end of a vertical feed link 43 so as to be rotatable about the Y axis, and the other end of the vertical feed link 43 is connected to the front end of the feed table 5 so as to be rotatable about the Y axis.

Further, the vertical feed wrist 42 has a swing end extending substantially rearward and a swing end reciprocating in the vertical direction.

Therefore, if a reciprocating rotational motion is input from the lower shaft 15 to the vertical feed shaft 41 via the vertical crank mechanism 44, the swing end of the vertical feed arm 42 reciprocates in the vertical direction, and the vertical movement is imparted to the feed table 5 and the feed teeth 4 via the vertical feed connecting link 43.

Further, if the tightened state is loosened, the step screw 48 that couples the input wrist 47 and the vertical feed rod 46 can move along the long hole 471, and the coupling position of the vertical feed rod 46 can be adjusted in the longitudinal direction (the direction of the arrow S) of the input wrist 47. This allows the reciprocating rotation angle given from the lower shaft 15 to the upper and lower feed shafts 41 to be adjusted to increase or decrease, and also allows the vertical movement width of the feed teeth 4 to be adjusted. That is, the input arm 47 and the stepped screw 48 constitute an up-down movement width adjustment unit 49 for adjusting the up-down movement width of the feed gear.

The vertical feed arm 42 is held and fixed to the vertical feed shaft 41 by a screw 421. Therefore, if the screw 421 is loosened, the vertical feed arm 42 can be rotated with respect to the vertical feed shaft 41, and the shaft angle can be rotationally adjusted along the arrow H. Thus, if the vertical feed shaft 41 is fixed and the vertical feed arm 42 is rotationally adjusted, the feed table 5 and the feed teeth 4 move up and down via the vertical feed connecting link 43, and the heights thereof can be adjusted. That is, the holding structure of the vertical feed arm 42 and the screw 421 constitute a height adjusting section 50 for adjusting the height of the feed teeth 4.

[ horizontal feed mechanism ]

Fig. 3 is an oblique view of the horizontal feeding mechanism 60, and fig. 4 is an exploded oblique view of the horizontal feeding mechanism 60 and the feed amount adjusting mechanism 80. The horizontal feed mechanism 60 is disposed in a sewing machine bed portion not shown.

As shown in fig. 1, 3, and 4, the horizontal feed mechanism 60 includes: a horizontal feed shaft 61 along the Y-axis direction, which performs reciprocating rotational motion; a horizontal crank mechanism 64 for transmitting reciprocating rotational motion from the lower shaft 15 to the horizontal feed shaft 61 via a feed amount adjusting mechanism 80 described later; and a horizontal feed wrist 62 fixedly connected to the horizontal feed shaft 61 and oscillating back and forth together with the horizontal feed shaft 61.

Further, the horizontal crank mechanism 64 includes: a horizontal feed cam 65 formed of an eccentric cam fixedly coupled to the lower shaft 15; a horizontal feed lever 66 having one end rotatably coupled to the horizontal feed cam 65; an input arm 67 fixedly connected to the horizontal feed shaft 61 and input to be reciprocated from the horizontal feed rod 66; and a horizontal feed link 63 that links the other end of the horizontal feed rod 66 and the swing end of the input wrist 67.

The horizontal feed cam 65 is an outer peripheral cam having a circular portion on the outer periphery, and the lower shaft 15 penetrates through the eccentric position, and the horizontal feed cam 65 is fixed to the lower shaft 15.

The horizontal feed lever 66 has one end portion holding the outer periphery of the perfect circle portion of the horizontal feed cam 65 via a radial bearing, not shown, and the horizontal feed cam 65 is rotatable with respect to the horizontal feed lever 66. The other end of the horizontal feed lever 66 is directed upward, and if the horizontal feed cam 65 rotates together with the lower shaft 15, the one end of the horizontal feed lever 66 revolves around the lower shaft 15 in accordance with the amount of eccentricity of the horizontal feed cam 65, and the other end of the horizontal feed lever 66 reciprocates up and down.

The other end of the horizontal feed lever 66 is connected to one end of the horizontal feed connecting link 63 so as to be rotatable about the Y axis.

On the other hand, the input wrist 67 is fixedly supported at one end portion thereof to the right end portion of the horizontal feed shaft 61 in the Y-axis direction, and swings about the horizontal feed shaft 61. A swing end of the input arm 67 extends upward, and is coupled to the other end of the horizontal feed coupling link 63 so as to be rotatable about the Y axis.

A horizontal feed wrist 62 is held and fixed to a left end portion of the horizontal feed shaft 61, and the horizontal feed wrist 62 is capable of swinging integrally with the horizontal feed shaft 61. The swing end of the horizontal feed arm 62 is coupled to the rear end of the feed table 5 via a horizontal feed eccentric pin 68 so as to be rotatable about the Y axis. As shown in fig. 5 and 6, the eccentric pin 68 includes a first shaft portion 681 and a third shaft portion 683 inserted into the horizontal feed wrist 62, and a second shaft portion 682 inserted into the feed table 5, and the first shaft portion 681 and the third shaft portion 683 are formed concentrically, and only the second shaft portion 682 is eccentric. Therefore, if the eccentric horizontal feed pin 68 is rotated, the end of the feed table 5 on the horizontal feed wrist 62 side is displaced upward and downward, and the inclination of the feed teeth 4 can be adjusted.

Further, the horizontal feed wrist 62 has a swing end portion extending substantially upward, and the swing end portion reciprocates in the front-rear direction.

Therefore, if a reciprocating rotational motion is input to the horizontal feed shaft 61 from the lower shaft 15 via the horizontal crank mechanism 64, the swing end of the horizontal feed arm 62 reciprocates in the front-rear direction, and imparts a reciprocating forward-and-backward movement to the feed table 5 and the feed teeth 4.

The horizontal feed cam 65 is fixed to the lower shaft 15 by two grub screws 651, and if the grub screws 651 are loosened, the horizontal feed cam 65 can be rotated with respect to the lower shaft 15, and the shaft angle can be adjusted in the direction of the arrow P. This allows the phase of the reciprocating rotational motion imparted from the lower shaft 15 to the horizontal feed shaft 61 to be adjusted, and also allows the phase of the horizontal motion of the feed teeth 4 to be adjusted. That is, the horizontal feed cam 65 and the grub screw 651 constitute a phase adjusting portion 69 for adjusting the phase of the reciprocating forward and backward movement of the feed teeth 4 with respect to the shaft angle of the lower shaft 15.

The horizontal feed wrist 62 is held and fixed to the horizontal feed shaft 61 by a screw, not shown. Therefore, if the screw is loosened, the horizontal feed wrist 62 can be rotated with respect to the horizontal feed shaft 61, and the shaft angle can be rotationally adjusted along arrow F. Thus, if the horizontal feed shaft 61 is fixed and the horizontal feed arm 62 is rotationally adjusted, the feed table 5 and the feed teeth 4 move forward and backward, and the forward and backward positions thereof can be adjusted. That is, the holding structure and the screws of the horizontal feed arm 62 constitute a horizontal position adjusting unit that adjusts the forward and backward positions of the feed dog 4 with respect to the needle fall position.

[ feed amount adjusting mechanism ]

The feed amount adjusting mechanism 80 adjusts the reciprocating rotation angle transmitted to the horizontal feed shaft 61 by regulating the movement direction of the connecting portion between the horizontal feed lever 66 of the horizontal feed mechanism 60 and the horizontal feed connecting link 63 and changing the angle about the Y axis of the movement direction.

As shown in fig. 1 and 4, the feed amount adjusting mechanism 80 includes: a pair of sliders 81 (only one is shown) attached to a connection portion between the horizontal feed lever 66 and the horizontal feed connection link 63 so as to be rotatable about the Y axis; a pair of guide portions 82 that slidably support the respective sliders 81; a slider block 83 which holds the pair of guide portions 82 and is supported in the sewing machine bed portion so as to be rotatable about the Y axis; a feed amount adjusting motor 84 that rotates the slider block 83 to an arbitrary rotation angle; a rotary arm 85 attached to an output shaft of the feed amount adjustment motor 84 that faces the Y axis direction; and a feed amount adjusting link 86 that links the pivot end of the pivot arm 85 and the slider block 83.

The slider block 83 has a substantially cylindrical shape, and the guide grooves formed in the pair of guide portions 82 hold the guide portions 82 so as to be substantially along the diameter direction of the slider block 83.

The pair of sliders 81 are constrained to be slidably supported along a guide groove formed in the guide portion 82, and the coupling portion between the horizontal feed rod 66 and the horizontal feed coupling link 63 reciprocates along the guide groove. The guide groove is formed in an arc shape along the locus of rotation of the horizontal feed connecting link 63.

Further, if the slider block 83 is rotated by driving the feed amount adjustment motor 84 via the pivot arm 85 and the feed amount adjustment coupling link 86, the direction of the groove of the guide portion 82 is also rotated about the Y axis, and the moving direction of the coupling portion between the horizontal feed lever 66 and the horizontal feed coupling link 63 is also changed.

At this time, if the orientation of the guide groove of the guide portion 82 is adjusted to be closer to the X-axis direction, the range of the reciprocating rotation angle of the horizontal feed shaft 61 becomes larger, and the width of the reciprocating back-and-forth movement in the feed direction of the feed teeth 4 becomes larger. More specifically, with respect to the position of the slider block 83 at which the feed pitch becomes 0, if the slider block 83 is rotated counterclockwise when viewed from the left direction, the feed pitch in the forward feed direction becomes large, and if the slider block 83 is rotated clockwise when viewed from the left direction, the feed pitch in the reverse feed direction becomes large.

Further, if the slider block 83 is rotated so that the orientation of the guide groove of the guide portion 82 is close to the Z-axis direction, the range of the reciprocating rotation angle of the horizontal feed shaft 61 becomes small, and the width of the reciprocating forward and backward movement in the feed direction of the feed teeth 4 also becomes small, so that the feed pitch approaches 0.

[ Sewing operation of the sewing machine ]

When the sewing machine motor 13 is driven, the sewing needle up-down moving mechanism 20 moves the two needle bars 12 up and down to start sewing.

At this time, the lower shaft 15 is also rotated by the driving of the sewing machine motor 13, and the vertical feed shaft 41 is reciprocated by the vertical crank mechanism 44 in the vertical feed mechanism 40. Thereby, the feed table 5 and the feed teeth 4 are reciprocated up and down by the vertical feed arm 42.

In the horizontal feed mechanism 60, the horizontal feed shaft 61 is reciprocated by the horizontal crank mechanism 64. Thereby, the feed table 5 and the feed teeth 4 are reciprocated back and forth by the horizontal feed arm 62.

By synchronously inputting reciprocating up-and-down movement and reciprocating back-and-forth movement to the feeding table 5, the feeding teeth 4 can perform long circular movement along the X-Z plane, and the sewed object on the needle plate 14 is conveyed forward at a constant sewing pitch.

[ technical effects of embodiments of the invention ]

The vertical feed mechanism 40 of the sewing machine 10 includes: an up-down feed shaft 41 to which reciprocating rotation motion is imparted from the lower shaft 15 by an up-down crank mechanism 44; and a height adjusting section 50 for adjusting the height of the feed teeth 4 by adjusting the angle of the vertical feed arm 42 with respect to the vertical feed shaft 41.

As described above, if the angle of the vertical feed arm 42 with respect to the vertical feed shaft 41 is changed, the distal end portion of the feed table 5 connected via the vertical feed connecting link 43 moves up and down, and the height of the feed teeth 4 can be adjusted.

Further, when the height of the feed teeth 4 is adjusted by changing the angle of the vertical feed arm 42 with respect to the vertical feed shaft 41 as in the height adjusting section 50, since the angle fluctuation of the vertical feed lever 46 with respect to the lower shaft 15 and the vertical feed cam 45 is not involved, the phase of the reciprocating vertical movement of the feed teeth 4 with respect to the shaft angle of the lower shaft 15 is not changed, and only the height adjustment can be performed.

Fig. 7 is a perspective view of an up-down feeding mechanism 40X as a comparative example. In the vertical feed mechanism 40X, one end of a vertical feed lever 46 is rotatably coupled to the lower shaft 15 via a vertical feed cam 45, and the other end is rotatably coupled to the front end of the feed table 5 about the Y axis.

The other end of the vertical feed rod 46 and the front end of the feed table 5 are connected by an adjustment pin 50X having an eccentric shaft, and the height of the feed dog 4 can be adjusted by rotating the adjustment pin 50X.

In the case of the vertical feed mechanism 40X as described above, the height of the feed teeth 4 varies by rotating the adjustment pin 50X, but the other end portion of the vertical feed lever 46 also rotates along with this, and therefore the phase of the reciprocating vertical movement of the feed teeth 4 with respect to the shaft angle of the lower shaft 15 inevitably varies.

Fig. 8 shows a movement locus of the feed teeth 4 in a case where the height adjustment of the feed teeth 4 is performed by the height adjusting section 50 of the vertical feed mechanism 40 as an embodiment.

Fig. 9 shows a moving locus of the feed teeth 4 in the case where the height adjustment of the feed teeth 4 is performed by the adjustment pin 50X of the vertical feed mechanism 40X as a comparative example.

In any case, the solid line shows the state before adjustment, the broken line shows the case where the feed teeth 4 are adjusted upward, and the broken line shows the case where the feed teeth 4 are adjusted downward.

As can be seen by comparing these, in the case of the height adjusting section 50 of the up-and-down feeding mechanism 40, when the feed teeth 4 are adjusted in any of the upward and downward directions, it is found that the phase variation of the reciprocating up-and-down movement of the feed teeth 4 with respect to the shaft angle of the lower shaft 15 hardly occurs. That is, the movement locus described by the feed teeth 4 is horizontally moved only upward and downward, and the positional change in the feed direction of the feed teeth 4 does not occur.

In the case of the adjustment pin 50X of the up-and-down feeding mechanism 40X, since the phase of the reciprocating up-and-down movement of the feed teeth 4 with respect to the axial angle of the lower shaft 15 varies when the feed teeth 4 are adjusted in either the upward or downward direction, it is known that the movement trajectory of the feed teeth 4 moves forward and backward.

The vertical feed mechanism 40 of the sewing machine 10 further includes a vertical movement width adjustment unit 49, and the vertical movement width adjustment unit 49 adjusts the vertical movement width of the feed gear 4 by moving and adjusting the connection position between the other end of the vertical feed lever 46 and the input arm 47 along the input arm 47.

Fig. 10 shows the movement locus of the feed teeth 4 in the case where the up-down movement width adjustment of the feed teeth 4 is performed by the up-down movement width adjustment part 49 of the up-down feeding mechanism 40. The solid line shows a state before adjustment, the broken line shows a case where the vertical movement width of the feed teeth 4 is enlarged, and the broken line shows a case where the vertical movement width is reduced.

As shown in the figure, the vertical movement width of the feed teeth 4 can be adjusted as shown in fig. 10 by loosening and moving the step screw 48 of the vertical movement width adjusting section 49. Therefore, the vertical movement range of the feed teeth 4 can be adjusted by a simple operation without requiring a troublesome operation such as replacement with the vertical feed cam 45 having a different eccentric amount, and various sewing materials can be easily sewn.

Further, the horizontal feed mechanism 60 of the sewing machine 10 includes: a horizontal feed shaft 61 that performs reciprocating rotational motion by a horizontal crank mechanism 64; and a phase adjusting section 69 for adjusting the phase of the reciprocating back and forth movement of the feed teeth 4 with respect to the axial angle of the lower shaft 15 by the axial angle adjustment of the horizontal feed cam 65 with respect to the horizontal feed shaft 61.

Fig. 11 shows the movement trajectory of the feed teeth 4 when the phase of the reciprocating back and forth movement is adjusted by the phase adjusting section 69, fig. 11 (a) shows the state before the adjustment, fig. 11 (B) shows the state in which the phase is advanced by 10 °, fig. 11 (C) shows the state in which the phase is advanced by 20 °, fig. 11 (D) shows the state in which the phase is retarded by 10 °, and fig. 11 (E) shows the state in which the phase is retarded by 20 °.

As described above, the feed dog 4 can be fed in various movement trajectories by a simple adjustment operation by the vertical movement width adjustment section 49, and appropriate sewing can be performed for various kinds of sewn objects.

As can be seen from fig. 2 and 3, the sewing machine 10 is arranged such that the vertical feed shaft 41 is located on the front side and the horizontal feed shaft 61 is located on the rear side with respect to the lower shaft 15, and the horizontal feed shaft 61, the lower shaft 15, and the vertical feed shaft 41 are arranged in this order from the upstream side to the downstream side in the feed direction of the workpiece in a plan view.

Therefore, the trajectory of the feed teeth 4 is likely to have a trajectory (for example, a trajectory as shown in fig. 11 (D)) that is higher on the upstream side and lower on the downstream side in the feed direction, and the feed force of the workpiece can be increased.

Claims

1. A needle feed sewing machine having:

a sewing machine motor;

a lower shaft rotationally driven by the sewing machine motor;

the needle feed sewing machine is characterized in that,

the horizontal feeding mechanism comprises:

a horizontal feed shaft;

the vertical feeding mechanism comprises:

an upper and lower feed shaft which performs reciprocating rotation;

2. The needle feed sewing machine of claim 1,

3. The needle feed sewing machine according to claim 1 or 2,

4. The needle feed sewing machine according to claim 1 or 2,

5. The needle feed sewing machine of claim 3,

6. The needle feed sewing machine of claim 4,

has a feed amount adjusting mechanism for adjusting the feed distance,

the feed amount adjusting mechanism includes:

a slider block having the guide portion; and

7. The needle feed sewing machine of claim 5,

has a feed amount adjusting mechanism for adjusting the feed distance,

the feed amount adjusting mechanism includes:

a slider block having the guide portion; and