JPH01303195A - Hook oiling device for sewing machine - Google Patents

Abstract

PURPOSE:To extremely stably supply a lubricating oil through an oil conveying tube to a supplying part by composing the title device of an oil conveying path and a fixed quantity oil conveying device to hold the constant height of the position of the oil surface of the lubricating oil to be stored for the opening edge of the oil conveying tube and supply the lubricating oil of constant pressure to the opening edge of the oil conveying tube all the time by the potential energy. CONSTITUTION:When a rotating shaft 2 of a rotating hook 1 rotates, the lubricating oil collides with the inner circumferential surface of an oil conveying tube 2 by centrifugal force. Since this inner circumferential surface is made into a taper shape, the diameter of which becomes larger as it goes upward, the collided lubricating oil successively moves upward along a wall surface, passes through an oil conveying path 1b, reaches the opening edge of a track groove 1a of the rotating hook 1, and after that lubricates a necessary sliding part. Here, since the pressure of the lubricating oil at the opening edge of the oil conveying tube 2a occurs due to the elevation difference between the opening edge and the upper edge surface of a storing part 8a, and since the pressure of the lubricating oil to flow in the oil conveying tube 2a can be held constant all the time when the elevation difference is constant, oil quantity conveyed and supplied from the oil conveying tube 2a to the track groove 1a can be constant all the time by fixing the position of a control needle 9 as an oil conveying quantity variable mechanism to a prescribed position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for supplying lubricating oil to a rotating rotary rotary hook, and more particularly to a sliding portion of an outer rotary hook.

[Prior Art J A hook oil supply device for a sewing machine has been proposed as shown in FIG. 3. In other words, the rotating shaft 2 of the outer pot 1 has
A storage hole 2a is formed having an inner circumferential surface that slopes away from the axial direction as it goes upward, and its lower end is immersed in the lubricating oil in the storage tank 4. The storage hole 2a houses an oil wick 3 whose lower end is immersed in the lubricating oil in the storage tank 4.

, 5 is a first supply hole formed in the bottom part 1b of the outer pot 1 and has one end opening at the upper part of the storage hole 2a; 6 is formed in the side W 1 c of the outer pot 1, and the lower end is connected to the first supply hole. A second supply hole communicating with the other end of the supply hole 5, the upper end of which is connected to the outer hook track groove 1a.
It is designed to supply lubricating oil to the sliding parts. Reference numeral 6a denotes an oil wick inserted into the second supply hole 6, and 7 is an oil amount adjustment screw for finely adjusting the amount of lubricating oil supplied by contacting the oil wick 6a and changing its cross-sectional area.

When the rotary shaft 2 of the outer pot 1 is rotationally driven, the lubricating oil in the storage tank 4 is transferred to the supply hole by the synergistic effect of the penetrating action of the oil wick 3 in the storage hole 2a and the inclined surface of the storage hole 2a. can be stably supplied.

In addition, the amount of lubricating oil supplied to the raceway 1a of the outer hook 1 can be finely adjusted by using the oil volume adjustment screw installed in the middle of the supply path that leads the lubricant to the raceway 1a of the outer hook 1. It has become.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional technology, even if the oil amount adjustment screw is fixed at a constant value, the amount of lubricating oil supplied to the supply point fluctuates greatly, and the amount of supplied lubricating oil changes. If the lubricating oil is too low, the sliding portion will seize; if the lubricating oil is too high, the lubricating oil will scatter from the sliding portion, causing problems such as oil stains on the bobbin thread. The causes of such large fluctuations in the amount of lubricating oil supplied are as follows.

(a) Since the supply amount from the plunger pump that supplies lubricating oil from the oil pan at the bottom of the sewing machine to the storage tank constantly fluctuates, the outer hook rotating shaft is immersed in the lubricating oil in the storage tank. Since the pressure on the lower end surface of the oil fluctuates, the amount of oil supplied will fluctuate even if the oil volume adjustment screw is held at a constant position.

The reason why the amount of oil fed by the plunger pump constantly fluctuates is due to phenomena such as air suction during operation and cavitation, but it is impossible to completely seal the plunger pump to prevent these phenomena.

(b) The oil core inserted into the storage hole of the rotating shaft is made of thread, felt, etc., so it may become clogged with use.At the beginning of use, oil flows well, that is, it does not reach the oil supply point. When the supply amount increases and clogging progresses, conversely, oil passage becomes poor and the supply amount decreases.

Furthermore, the oil wick made of felt etc. gets clogged in a relatively short time, so constant monitoring is required to prevent lubricating oil from being insufficiently supplied at the oil supply point and causing seizing. Not only is this troublesome, but also the replacement of the oil wick itself requires very complicated work.

[Means for Solving the Problems] This invention provides an oil supply device for a rotating rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary rotary coils. The position of the oil feed path for supplying oil and the level of the stored lubricating oil is kept at a constant height with respect to the open end of the oil feed pipe, and the potential energy causes the lubricating oil to reach the open end of the oil feed pipe. This invention attempts to solve the problems of the prior art described above by comprising a metering oil feeder that always supplies lubricating oil at a constant pressure. The level of lubricating oil stored in the metering oil feeder that sends out oil is always maintained at a constant position higher than the open end of the oil pipe, and the lubricating oil uses its potential energy to increase the oil level in the oil pipe. The lubricating oil is delivered to the open end, and the pressure of the lubricating oil at this open end is always constant, making the supply of lubricating oil to the supply point via the oil delivery pipe extremely stable.

[Embodiments of the invention] The present invention will be described in detail based on the drawings.

The same or equivalent parts as in the prior art are given the same reference numerals, and redundant explanation will be omitted.

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

In the figure, 1b is an oil feed passage formed through the bottom 1c and side wall 1d of the outer hook 1, and one end thereof is connected to the track groove 1 of the outer hook 1.
A, the other end communicates with an end on the outer hook side of an oil feed pipe 2a formed through the rotating shaft 2 of the outer hook.

The oil feed pipe 2a is formed to have an inner circumferential surface that slopes away from the axial direction toward the outer shell, and its mouth end projects into the oil tank 4.

Reference numeral 8 denotes a metering oil feeder interposed between the oil tank 4 and a plunger pump for oil feeding (not shown). The metered oil feeder 8 includes a reservoir 8a with an open top, an inlet 8b into which lubricating oil from the plunger pump flows, and an outlet 8.
It is composed of c.

The outflow path 8C is provided with an adjustment needle 9 as an oil feed rate variable mechanism, which moves back and forth in the horizontal portion of the outflow path 8c to adjust the flow rate of lubricating oil.

The upper surface of the reservoir 8a is always open as described above,
The lubricating oil supplied from the plunger pump through the tube 10 attached to the inlet 8b overflows so that the oil level is always located at the upper end surface of the reservoir 8a.

Further, the metered oil feeder 8 is provided at an appropriate position so that the upper end surface of the reservoir 8a is higher than the open end of the oil feed pipe 2a.

Note that 11 is a tube that connects the end of the outflow path 8C and the intake port 4a of the oil tank 4.

Next, the action will be explained.

When the rotating shaft 2 of the outer hook 1 is not rotating, the storage portion 8a
The lubricating oil flows into the oil tank 4 via the outflow path 8C and the tube 11 due to potential energy, and is sequentially transferred to the oil feed pipe 2a.
After reaching the opening end of the oil feed pipe 2a, the oil level in the oil feed pipe 2a rises so that the oil level in the oil feed pipe 2a becomes equal to the oil level in the reservoir 8a, that is, the same height as the upper end surface of the reservoir 8a.

When the rotary shaft 2 of the outer pot 1 rotates, the lubricating oil collides with the inner circumferential surface of the oil feed pipe 2a due to centrifugal force. As described above, this inner circumferential surface has a tapered shape that expands in diameter upward, so the colliding lubricating oil sequentially moves upward along the wall surface, passes through the oil feed path 1b, and enters the track of the outer hook 1. After reaching the open end of the groove 1a, the required sliding parts are lubricated.

By the way, the pressure of the lubricating oil at the mouth end of the oil feed pipe 2a is
This is caused by the height difference between the mouth end and the upper end surface of the reservoir 8a, so if the height difference is constant, the pressure of the lubricating oil flowing into the oil feed pipe 2a is always kept constant, so the oil feed amount can be varied. If the position of the adjusting needle 9 as a mechanism is fixed at a predetermined position, the amount of oil fed from the oil feed pipe 2a to the track groove 1a will always be constant. Also, since the above potential energy is very small,
The flow rate flowing from the storage part 8a to the oil tank 4 is small,
Fine adjustment can be made using the adjustment needle 9.

FIG. 2 is a diagram showing another embodiment of the invention.

In this embodiment, unlike the above-mentioned horizontal pot, the rotary pot is of a vertical type. The lubricating oil is directly fed from the metered oil feeder 8 to the mouth end of the oil feed pipe 2a, and other structures and functions are the same as in the previous embodiment.

[Effects of the Invention] With the above-described configuration and operation, this invention can supply a constant amount of lubricating oil to the sliding parts of the rotary hook, thereby preventing oil stains on the sewing product and burning of the sliding parts. It does not cause problems such as those caused by attaching.

Furthermore, since there is no need for an oil wick in the oil feed pipe provided within the rotary shaft of the outer hook, there is no need to replace the oil wick, which improves sewing efficiency.

[Brief explanation of the drawing]

1 and 2 are partially omitted sectional views showing a first embodiment and a second embodiment of the present invention, respectively, and FIG. 3 is a vertical sectional view showing a prior art. In the figure, 1... Outer pot 1b... Oil feed path 2... Rotating shaft 2a... Oil feed pipe 8... Metering oil feeder 8a... Reservoir 8b... Inflow port 8c...Outflow channel 9...Name of applicant of variable oil amount mechanism Juki Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] An oil feed pipe that supplies lubricating oil to the sliding parts of the outer hook, an oil feed path formed in the outer hook that communicates with the raceway of the outer hook at one end and the oil feed pipe at the other end, It consists of a fixed quantity oil feeder for feeding lubricating oil to the pipe, and the oil feed pipe is attached to the outer case so as to have an inner circumferential surface that slopes away from the axial direction toward the outer case. The metering oil feeder is formed on a rotating shaft, and includes a reservoir portion with an upper opening, a lubricating oil inlet provided in the reservoir portion, and a lubricant oil inlet provided in the reservoir portion and having a variable oil feed amount mechanism. The oil level in the reservoir of the metering oil feeder is maintained at a higher position than the mouth end position of the oil feed pipe, and a fixed amount of lubricating oil is constantly supplied to the oil feed pipe. A sewing machine hook oil supply device characterized by: