JPH0560483U - Full rotary hook of sewing machine - Google Patents

Abstract

(57) [Summary] [Structure] The outer hook 1 has a guide passage 23 and an oil amount adjusting passage 24.
And a bolt 25 having a tapered tip portion is screwed into the oil amount adjusting passage 24. [Effect] The supply amount of the lubricating oil can be easily and finely adjusted only by rotationally displacing the oil amount adjusting bolt 25, and the responsiveness of the lubricating oil supplied to the rail groove 6 at the time of the outer hook rotation is improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a full rotary hook of a sewing machine, and more particularly, to a structure for adjusting the amount of lubricating oil supplied to a rail groove of an outer hook.

[0002]

[Prior Art]

 Typical prior art is disclosed in, for example, Japanese Patent Publication No. 59-9195. In this prior art, as shown in FIG. 10, in order to supply the lubricating oil to the rail groove 51 of the outer hook 50, a lubricating oil supply pipe 52 is arranged in the outer hook 50 at a position displaced from the axis L10. The lubricating oil sucked up by the spiral oil supply passage 55 formed in the rotary shaft 54 is supplied to the rail groove 51 through the supply pipe 52. In order to adjust the flow rate of the lubricating oil, a bolt 53 is screwed into the outer hook 50, the tip of the bolt 53 faces the supply pipe 52, and this bolt 53 is rotationally displaced to rotate the axis L11 of the supply pipe 52. The angle of inclination of the outer hook with respect to the axis L10 is adjusted to adjust the flow rate of the lubricating oil.

[0003]

[Problems to be solved by the device]

 In the prior art as described above, it is difficult to make a minute adjustment of the flow rate of the lubricating oil only by adjusting the angle of the axis L11 of the supply pipe 52, and as described later with reference to FIG. 6, for example, 25 mg / Fine adjustment of the flow rate below the minute is practically impossible. Moreover, the length of the supply pipe 52 along the direction of the axis L11 is relatively long, and therefore, when the outer hook is started to rotate, the lubricating oil has to go up its relatively long path, resulting in poor responsiveness. Have the problem.

An object of the present invention is to solve the above-mentioned technical problems, to enable fine adjustment of the amount of lubricating oil introduced into the outer raceway groove with a simple structure and to improve responsiveness. It is to provide a full rotary hook of the sewing machine that is made possible.

[0005]

Means for Solving the Problems The present invention is configured to guide lubricating oil from a supply passage formed in a shaft portion of an outer hook to a rail groove formed in an inner peripheral surface of the outer hook for oil supply. In the full rotary hook of the sewing machine, a guide passage is formed in the outer hook that communicates with the supply passage and is located radially outward of the supply passage, and intersects with the guide passage. An oil amount adjusting passage extending in the radial direction is provided, and an oil amount adjusting bolt which tapers toward the tip is screwed into the oil amount adjusting passage. There is up to full rotation.

[0006]

[Action]

 According to the present invention, in all the rotary hooks of the sewing machine, the lubricating oil extends in the radial direction between the supply passage and the guide passage to the rail groove formed at a position displaced in the radial direction. A quantity adjusting passage is formed, and an oil quantity adjusting bolt is screwed into the quantity adjusting passage. By rotationally displacing the oil amount adjusting bolt, the opening area of the guide passage facing the oil amount adjusting passage can be finely adjusted by the tapered outer peripheral surface near the tip of the bolt, and the amount of lubricating oil can be reduced. Flow rate can be adjusted.

[0007]

【Example】

 1 is an enlarged cross-sectional view showing an outer hook 1 according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing the entire structure of a horizontal full rotary hook having the outer hook 1, and FIG. FIG. 3 is a sectional view taken along the section line III-III in FIG. The outer hook 1 includes an outer hook main body 2 and a shaft mounting portion 3, and a rotary shaft 4 is fixed to the shaft mounting portion 3. The rotating shaft 4 is rotatably supported by a bearing 5. The outer hook body 2 is formed in a substantially cylindrical shape with a bottom, and a groove 6 is formed on the inner peripheral surface of the outer hook body 2 by an inner hook retainer 9 along the circumferential direction. The rail 8 of the inner rotary hook 7 is fitted into the rail groove 6, and the inner rotary hook 7 is stored in the storage portion 2 a of the main rotary body 2. The inner hook 7 is prevented by the inner hook retainer 9 from being removed from the outer hook main body 2. The rotation of the inner rotary hook 7 is blocked by a rotary hook 11 provided on the needle plate 10.

The bearing 5 has a space 5 a, and an oil supply pipe 12 for feeding lubricating oil into the space 5 a is connected to the bearing 5. An annular oil drain receiving groove 13 is formed on the end surface 5b of the bearing 5 facing the outer hook 1 and its axis is concentric with the axis L1 of the rotary shaft 4. An oil drain passage 14 is provided in the bearing 5 so as to communicate with the oil drain receiving groove 13. A cover 28 facing the shaft mounting portion 3 of the outer hook 1 is fixed to the outer peripheral surface of the bearing 5, and the shaft mounting portion 3 is enveloped with a gap.

A spiral groove 4 a is provided in a portion of the rotating shaft 4 facing the space 5 a of the bearing 5, and a through hole 4 b is provided at an uppermost portion of the groove 4 a inward in the radial direction of the rotating shaft 4. It is provided. A first supply passage 15 is formed in communication with the through hole 4b so as to extend upward along the axis of the rotating shaft 4, which is the free end side of the through hole 4b.

A substantially frusto-conical oil chamber 16 is formed at the bottom of the storage portion 2 a of the inner rotary hook body 7 of the outer rotary hook body 2, and an upper portion thereof is closed by a partition plate 17. The upper end of the rotary shaft 4 faces the oil chamber 16 and communicates with the first supply passage 15. The second supply passage 18 is formed so as to be inclined radially outward from the bottom peripheral portion of the oil chamber 16 toward the shaft mounting portion 3 on the base end side of the outer hook 1. The lower end of the second supply passage 18 communicates with an annular groove 19 provided on the lower surface of the shaft mounting portion 3. An annulus 20 is fitted along the outer side surface of the groove 19 in the radial direction, whereby an annular oil sump 21 is formed.

A third supply passage 22 is formed on the opposite side of the second supply passage 18 with respect to the rotating shaft 4. The third supply passage 22 is formed upward from the peripheral portion of the oil sump 21, and its axis B is directed upwardly with respect to a line A parallel to the axis L1 of the rotating shaft 4 by an angle θ1 outward in the radial direction. Only inclined. The third supply passage 22 is formed up to near the lower end of the outer hook body 2.

A guide passage 23 is formed substantially parallel to the third supply passage 22 and offset outward in the radial direction. The guide passage 23 is formed downward from the storage portion 2a of the outer hook body 2, and is drilled to a position near the upper end of the third supply passage 22.

As shown in FIG. 3, the first supply passage 15, the second supply passage 18, the third supply passage 22 and the guide passage 23 are positioned substantially on the same line in a plane perpendicular to the axis of the rotary shaft 4. However, the axis of the oil quantity adjusting passage 24 substantially coincides with the axis. Further, the free end side opening P1 of the third supply passage 22 is located radially outward with respect to the axis L1 of the rotary shaft 4 with respect to the base end side opening P2 of the second supply passage 18. Then, the oil amount adjusting passage 24 is opened so as to face it. Therefore, the lubricating oil in the third supply passage 22 is guided upward by the action of the centrifugal force due to the rotation of the outer hook 1, and the lubricating oil introduced in the oil amount adjusting passage 24 is The pressure is relatively high due to the pressing force of the lubricating oil rising inside and the centrifugal force due to the rotation of the outer hook 1.

An oil amount adjusting passage 24 is provided in the outer hook main body 2 so as to communicate the third supply passage 22 and the guide passage 23 and along a radial direction perpendicular to the axis of the rotating shaft 4. An inner thread is applied to the inner peripheral surface of the oil amount adjusting passage 24, and an oil amount adjusting bolt 25 shown in FIG. 4 is screwed into the oil amount adjusting passage 24. An outer peripheral surface 40 in the shape of a truncated cone is formed and faces the third supply passage 22. The rate of change in the amount of oil corresponding to the screw advance / screw displacement of the bolt 25 can be changed according to the inclination angle of the outer peripheral surface 40 of the tip portion with respect to the axis of the bolt 25. The oil amount adjusting bolt 25 is a so-called hexagon socket set screw, and is engraved with an external screw, and a hexagon wrench engaging recess 26 is formed at the rear end portion. The engaging recess 26 is formed, for example, in a regular hexagonal cross section perpendicular to the axis.

As shown in FIG. 5, a generally L-shaped communication groove 27 is formed on the inner surface of the housing portion 2 a of the outer hook body 2 from the guide passage 23 to the rail groove 6. The rear wall 27a of the connecting groove 27 faces upward and forms an angle θ2 radially outward with respect to the axis of the rotating shaft 4. The bottom portion 27b of the communication groove 27 is formed along the radial direction and is inclined slightly downward toward the outside in the radial direction.

The operation of the outer hook 1 having the above configuration will be described. The rotary shaft 4 is rotationally driven by a driving means (not shown), which causes the outer hook 1 to be rotationally driven. The rotation of the inner hook 7 is blocked by a hook stopper 11. At this time, the lubricating oil is pumped from the oil supply pipe 12 into the space 5a of the bearing 5 by a pump (not shown). The lubricating oil sent under pressure flows along the spiral groove 4a by the rotation of the rotary shaft 4 and the pressure of the pump, passes through the through hole 4b and the first supply passage 15, and then reaches the outer hook main body 2. It is sent to the formed oil chamber 16.

The lubricating oil sent to the oil chamber 16 is accumulated around the side of the oil chamber 16 by the centrifugal force generated by the rotation of the outer hook 1 and is inclined outward in the radial direction by the centrifugal force and its own weight. It passes through the two supply passages 18 and is guided to the oil sump 21. Of the lubricating oil guided to the oil sump 21, the excess lubricating oil flows along the inner peripheral surface of the ring body 20 and drops on the end surface 5b of the bearing 5. The lubricating oil dropped on the end surface 5b of the bearing 5 is returned from the oil drain receiving groove 13 through the oil drain passage 14 to, for example, an oil tank (not shown). At this time, the cover 28 prevents the lubricating oil from scattering.

The lubricating oil accumulated in the oil sump 21 rises in the third supply passage 22 and is guided to the oil amount adjustment passage 24 by the centrifugal force generated by the rotation of the outer hook 1. By increasing the inclination θ1 of the third supply passage 22, the amount of lubricating oil introduced into the oil amount adjustment passage 24 also increases.

The lubricating oil guided to the oil amount adjusting passage 24 through the third supply passage 22 is an opening facing the outer peripheral surface 40 of the tip of the oil amount adjusting bolt 25 and the oil amount adjusting passage 24 of the guide passage 23. From the gap with the portion P3, it is guided to the communication groove 27 through the guide passage 23. At this time, by displacing the oil amount adjusting bolt 25 inward or outward in the radial direction, the opening area of the opening P3 is adjusted according to the distance between the proposed passage 23 and the tip of the oil amount adjusting bolt 25. The amount of the lubricating oil flowing into the guide passage 23 can be finely adjusted. The displacement of the oil amount adjusting bolt 25 inward or outward in the radial direction can be performed only by rotating the oil amount adjusting bolt 25, and as shown by a line L3 in FIG. It is possible to make extremely minute adjustments compared to the oil amount indicated by line L4. When a finer adjustment is required, it is possible by further reducing the pitch of the screws of the oil amount adjusting bolt 25 and the oil amount adjusting passage 24. An oil seal is provided at a screwed portion of the oil amount adjusting passage 24 and the oil amount adjusting bolt 25 radially outward of the drilled position of the guide passage 23, so that the lubricating oil is transferred to the outside of the outer hook main body 2. It is prevented from leaking.

As described above, the lubricating oil adjusted in the oil amount adjusting passage 24 is guided from the guide passage 23 to the communication groove 27 by the centrifugal force generated by the rotation of the outer hook 1. The lubricating oil guided to the connecting groove 27 rises along the rear wall 27a of the connecting groove 27 by centrifugal force and is supplied to the rail groove 6 formed in the outer hook body 2.

The lubricating oil accumulated in the bottom portion 27b of the connecting groove 27 due to the stop of the rotation of the outer hook 1 is quickly supplied to the rail groove 6 when the outer hook 1 is re-driven. Moreover, since the lubricating oil is stored in the guide passage 23, even if there is a gap between the opening P3 of the guide passage 23 and the tip of the oil adjusting bolt 25, the lubricating oil has a relatively high viscosity. As a result, the lubricating oil remains stored in the guide passage 23, which also allows the lubricating oil to be quickly supplied to the rail groove 6 via the connecting groove 27 when the outer hook 1 is re-driven. it can.

FIG. 7 is a sectional view of another embodiment of the present invention. This embodiment is similar to the above-mentioned embodiment, and the corresponding portions bear the same reference numerals. It should be noted that in the present embodiment, the second supply passage 18a is formed along the radial direction with the same axis as the oil amount adjustment passage 24a. The guide passage 23a is provided so as to pass through the oil amount adjusting passage 24a from the lower surface of the outer hook body 2 and communicate with the rail groove 6, and the vicinity of the lower end of the guide passage 23a is closed by a sealing body 30. The axis of the guide passage 23a is directed to the upper side of the outer hook body 2 and is inclined radially outward with respect to the axis of the rotary shaft 4 at an angle of θ3.

As shown in FIG. 8, the oil amount adjustment passage 24a has an insertion portion 24b inward in the radial direction. The axis of the insertion portion 24b coincides with the axis of the oil amount adjustment passage 24a, and the shaft portion 25b of the oil amount adjustment bolt 25a described later is inserted.

A right columnar shaft portion 25b is formed at the tip of the oil amount adjusting bolt 25a, and an outer peripheral surface 25c thereof is formed in a tapered shape, which is a so-called conical shape. The axis of the shaft portion 25b coincides with the axis of the oil amount adjusting bolt 25a.

In the present embodiment, similarly to the above-described embodiments, the lubricating oil fed into the oil chamber 16 is accumulated around the side portion of the oil chamber 16 due to the centrifugal force generated by the rotation of the outer hook 1, and the second supply oil is supplied. It is guided to the insertion portion 24b of the oil amount adjustment passage 24a through the supply passage 18a. Of the lubricating oil guided to the insertion portion 24b, excess lubricating oil passes through the third supply passage 22 and drips on the end surface 5b of the bearing 5, and then passes through the drain passage 14 and an oil tank (not shown). Is reduced to.

The remaining lubricating oil guided to the insertion portion 24b is the gap between the insertion portion 24b and the shaft portion 25b, and the gap between the outer screw of the oil amount adjusting bolt 25a and the inner screw of the oil amount adjusting passage 24a. Through the guide passage 23a.

Of the lubricating oil guided to the insertion portion 24b, the oil amount guided to the guide passage 23a is adjusted by rotating the oil amount adjustment bolt 25a when the shaft portion 25b is inserted into the insertion portion 24b. It is possible to adjust by changing the overlapping dimension L of the insertion portion 24b and the shaft portion 25b by the displacement. When the shaft portion 25b is not inserted through the insertion portion 24b, the amount of oil can be adjusted by changing the gap between the conical tip portion 25c of the shaft portion 25b and the end portion 24c of the insertion portion 24b. Is.

In this way, the lubricating oil guided to the guide passage 23 a is guided to the rail groove 6 by the centrifugal force generated by the rotation of the outer hook 1 to achieve oil supply. In this way, also in this embodiment, the same effect as that of the above-mentioned embodiment can be expected.

The present invention can be implemented not only in the horizontal full-rotation rotary hook, but also in the vertical full-rotation rotary hook.

[0030]

[Effect of the device]

 As described above, according to the present invention, the oil amount adjusting passage extending in the radial direction is provided between the supply passage and the guide passage, and the oil amount adjusting bolt is screwed into the oil amount adjusting passage to adjust the oil amount. The amount of lubricating oil supplied can be easily adjusted simply by rotationally displacing the bolt. Therefore, it is possible to easily adjust a minute amount of oil, for example, about 25 mg / min.

Further, since the lubricating oil is stored in the guide passage, the rotation of the outer hook is stopped, and there is a gap between the opening facing the oil amount adjusting passage of the guide passage and the tip of the bolt. Even in this state, since the opening area of the opening is very small, there is no risk that the lubricating oil in the guide passage will flow into the oil amount adjusting passage, and therefore the lubricating oil may be stored in the guide passage. This is possible, and when the outer hook is driven again, it becomes possible to quickly supply the lubricating oil in the guide passage to the rail groove, and it is possible to improve the responsiveness.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an outer hook 1 according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the overall configuration of a horizontal full rotary hook.

FIG. 3 is a sectional view taken along section line III-III in FIG.

FIG. 4 is a perspective view of an oil amount adjusting bolt 25.

FIG. 5 is a partially enlarged view of the vicinity of a communication groove 27.

FIG. 6 is a graph showing the relationship between the amount of oil and the rotation angle of the oil amount adjusting bolt according to the experimental results of the present inventor.

FIG. 7 is a cross-sectional view of another embodiment of the present invention.

FIG. 8 is a partial cross-sectional view in the vicinity of the oil amount adjustment passage 24a.

FIG. 9 is a cross-sectional view of another embodiment of the present invention.

FIG. 10 is a typical prior art cross-sectional view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer hook 4 Rotating shaft 6 Rail groove 8 Rail track 15 First supply passage 18, 18a Second supply passage 21 Oil sump 22 Third supply passage 23, 23a, 23b Guide passage 24, 24a Oil amount adjusting passage 24b Insertion portion 25 , 25a Oil amount adjustment bolt 25b Shaft

Claims (1)

[Scope of utility model registration request] 1. A full rotary hook of a sewing machine configured to guide lubricating oil from a supply passage formed in a shaft portion of an outer hook to a rail groove formed in an inner peripheral surface of the outer hook for oil supply. In the outer hook, a guide passage that communicates with the supply passage and is formed at a position radially outward of the supply passage, and an oil amount adjustment passage that intersects the guide passage and extends in the radial direction are provided. A full-rotation rotary hook of a sewing machine, characterized in that an oil amount adjusting bolt which is provided in the oil amount adjusting passage and is tapered toward the tip is screwed.