JP2000051560A - Lubricating oil recovery device for sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a hindrance from being generated even at the time of efficiently sucking lubricating oil together with air in the lubricating oil recovery device of a sewing machine for sucking and recovering the lubricating oil flowing out to a needle bar projected from a bearing through an oil discharge pipe. SOLUTION: A jetting pump 7 is connected to an oil supply pipe 6 connected to a trochoid pump 3. The jetting pump 7 is provided with a flow passage provided with a nozzle part 22a, a throat part and a diffuser part 22b, an oil discharge pipe connection part 18a is communicated to the throat part and the oil discharge pipe 18 is connected. When pressure oil passes through the flow passage 22, it is mixed with the lubricating oil sucked from the oil discharge pipe at the throat part and jetted into a machine from the diffuser part 22b. In the flow passage 22, the nozzle part 22a forms an acute angle to the extension of the diffuser part 22b and the oil discharge pipe connection part 18a also forms the acute angle to the extension of the diffuser part. Thus, the suction amount of the lubricating oil from the oil discharge pipe 18 is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for collecting lubricating oil supplied to a movement mechanism of a sewing machine, and more particularly to a device for collecting lubricating oil supplied to a needle bar.

[0002]

2. Description of the Related Art Generally, in an industrial sewing machine, an oil reservoir and an oil supply pump are provided below a bed to forcibly supply oil to rotating and sliding parts of a movement mechanism so as to prevent heat generation and wear of each part. It flows down naturally from each part or is forcibly recovered and returned to the oil sump.

In Japanese Utility Model Publication No. 6-10955, an oil immersion felt is provided in a bearing through which the needle bar penetrates to supply oil to the needle bar, and a needle bar projecting from the bearing faces an oil drain pipe connected to an oil supply pump. And contact the tip of the oil core passed through the oil drain pipe,
There is disclosed an apparatus in which lubricating oil flowing out of a bearing is forcibly collected by an oil supply pump. In addition, Tokiko Sho 38-
Japanese Patent No. 25489 discloses a sewing machine that drains oil in a hollow head that supports a needle bar by a pump action of a jet pump of an oil supply device and a siphon action of an oil drain pipe connected to the pump.

[0004]

As the needle bar moves up and down, the lubricating oil adhering to the needle bar protruding from the bearing is handled at the end of the bearing and scatters around to contaminate the fabric being sewn. become. In this regard, in Japanese Utility Model Publication No. 6-10955, the above problem does not occur because the lubricating oil flowing out to the needle bar protruding from the bearing is forcibly collected, but the oil supply pump may draw air together with the lubricating oil. is there.

A first object of the present invention is to provide an oil collecting apparatus for a sewing machine which does not cause a problem even if lubricating oil flowing out to a needle bar protruding from a bearing is sucked together with air. An object of the present invention is to provide a sewing machine oil recovery device that can efficiently perform oil recovery.

[0006]

According to a first aspect of the present invention, there is provided an oil supply pump, an oil supply pipe connected to a discharge port of the oil supply pump, and an oil supply pipe connected to the oil supply pipe. A jet pump connected to the jet pump at one end and a drain pipe facing the needle bar projecting from the bearing at the other end.
The jet pump has a flow path composed of an upstream nozzle portion and a downstream diffuser portion connected at the throat portion with the nozzle portion, and the connection portion of the oil drainage pipe communicates with the throat side of the diffuser portion. It is characterized by.

According to the present invention, the oil drained to the needle bar due to the negative pressure at the throat is sucked and collected through the oil drain pipe. According to a second aspect of the present invention, in order to achieve the second object, in the first aspect of the present invention, the flow path of the oil pump is bent at an obtuse angle between the nozzle portion and the diffuser portion, and the diffuser is diffused. The angle formed by the extension of the portion and the nozzle portion and the angle formed by the extension of the diffuser portion and the connection portion of the oil drainage pipe are each acute.

According to experiments by the present inventors, when the angle formed by the extension of the diffuser portion and the nozzle portion and the oil drain pipe are made acute, the oil drain pipe has an acute angle compared to the case where the diffuser portion and the nozzle portion are straight. It was confirmed that even if the rotation speeds were the same, the amount of lubricating oil suction increased, and oil recovery could be performed efficiently.

[0009]

1 to 3, a trochoid pump 3 as an oil supply pump is installed in a lower oil sump 2 of an overlock sewing machine 1 and is driven by a main shaft 4 via a worm gear 5 so as to have an oil sump. The lubricating oil sucked up from 2 is passed through the oil supply pipe 6 and supplied to the joint 6A. The lubricating oil supplied to the joint 6A is distributed into three parts. One of the distributed lubricating oils is supplied to various mechanisms of the sewing machine bed, and the other two are supplied to the oil jet pipe 6c and the jet pump 7 via the distributor 6B.

The lubricating oil discharged from the oil injection pipe 6C is supplied to various mechanisms of the sewing machine including the needle bar driving mechanism. The needle bar drive mechanism is disposed in the head 8 shown in FIG. 3, and is fixed to a crankshaft 9 which swings in conjunction with the main shaft 4.
Needle bar holder 1 that penetrates bearing 12 and is attached at the center
1a is connected to the swinging crank 11, and the needle bar 15 moves up and down by swinging of the swinging crank 11. Needle bar 1
An opening is formed around the needle bar 15 in the upper part of the bearing 12 through which the needle 5 penetrates, and lubricating oil jetted from the oil injection pipe 6C is attached to the opening in the upper part of the bearing 12 to supply oil to the needle bar. This is performed by impregnating the oiled cord 6a. The oil discharged after being supplied to the needle bar drive mechanism is returned to the oil reservoir 2 through the oil discharge hole 16.

The bearing 12 also has an opening formed on the lower side of the cloth feeding and delivery side. An oil drain pipe 18 connected to the jet pump 7 and penetrating the machine frame of the sewing machine is opened near this opening. I have. As shown in FIG. 4, the jet pump 7 includes an upstream nozzle portion 22a and a downstream diffuser portion 22b, and the nozzle portion 22a communicates with a throat portion 22c of the diffuser portion 22b and is bent at an obtuse angle with the diffuser portion. The flow path 22 is formed, and the end of the diffuser portion 22 b is open toward the worm gear 5. And the nozzle part 22a
Is connected to the oil supply pipe 6 via the distributor 6B,
The drainage pipe connecting portion 18a communicates with the throat portion 22c side of the diffuser portion 22b, and the drainage pipe 18 is connected thereto.
This oil drain pipe connection portion 18a is provided with a throat portion 22 as shown in FIG.
The angle α formed by the extension of the diffuser portion 22b downstream of c is an acute angle together with the angle β formed by the extension of the diffuser portion 22b and the nozzle portion 22a.

The operation of the jet pump 3 is such that when the pressure oil sent by the oil supply pump 3 is jetted from the nozzle 22a,
The oil discharge pipe 1 is formed by a pump action generated at the oil discharge pipe connection portion 18a.
Air 8 and lubricating oil flowing out of the bearing 12 are sucked and mixed in the throat 22c. Diffuser part 22b
The lubricating oil spouted from the worm gear 5 is sprayed onto the worm gear 5 and flows down into the oil sump 2. It should be noted that even if air is sucked together with the lubricating oil through the oil drain pipe 18, the air is discharged from the outlet of the flow path 22 together with the pressure oil, so that no trouble occurs.

[0013]

EXAMPLE 1 A jet pump 7 having an angle α of 20 ° and an angle β of 20 ° shown in FIG. 4 was used, the rotation speed of the sewing machine was 2000 rpm, and the discharge amount of pressure oil from the jet pump 7 was 320 ml /. The amount of suction from the oil drain pipe 18 at MIN was 2.9 ml / min, the number of revolutions was 4,000 rpm, and the amount of suction at 530 ml / min of pressure oil discharge was 5.8 ml / min.

Embodiment 2 Using a jet pump 7 having an angle α of 30 ° and an angle β of 20 ° shown in FIG. 4, the discharge speed when the rotation speed of the sewing machine is 2000 rpm and the discharge amount of the pressure oil is 350 ml / min. The amount of suction from the oil pipe 18 is 3.1 ml / min, the number of revolutions is 4000 rpm,
When the discharge amount of the pressurized oil is 580 ml / min, the suction amount is 5.
It was 9 ml / min.

COMPARATIVE EXAMPLE Using a jet pump 7 shown in FIG. 4 having an angle α of 30 ° and an angle β of 0 °, an oil drain pipe when the rotation speed of the sewing machine is 2000 rpm and the discharge amount of pressure oil is 450 ml / min. The suction port from No. 18 was 1.7 ml / min, the number of revolutions was 4000 rpm, and the suction rate when the discharge rate was 580 ml / min was 2.5 ml / min.

The above results are shown in Table 1 below.

[0017]

[Table 1]

As can be seen from the above results, the angle α is set to 2
In the jet pumps 7 of Examples 1 and 2 in which the angle was set to an acute angle of 0 ° or 30 ° and the angle β was also set to an acute angle of 20 °, the angle α was set to 30 °.
Although the angle β was 0 °, the angle β was 0 °, and the suction amount could be increased even if the discharge amount of the pressure oil was small as compared with the jet pump 7 of the comparative example in which the flow path 22 was straightened.

[0019]

According to the first aspect of the present invention, since the oil draining to the needle bar protruding from the bearing is recovered, the oil drain on the needle bar is handled by the bearing as the needle bar moves up and down. The problem of splashing and soiling the fabric being sewn is eliminated, and even if air is sucked in along with oil drainage through the oil drain pipe, it will only be released into the air inside the machine, causing no problems. It has the effect of not having anything.

According to the second aspect of the present invention, the drain oil can be efficiently sucked.

[Brief description of the drawings]

FIG. 1 is a front view showing a main part of an overlock sewing machine in a cross section.

FIG. 2 is a right side view showing a cross section of a main part of the overlock sewing machine.

FIG. 3 is a left side view of the same.

FIG. 4 is an enlarged view of a flow path of the jet pump.

[Explanation of symbols]

 1. Overlock sewing machine 2. Oil reservoir 3. Trochoid pump 4. Main shaft 5. Worm gear 6, 6a Oil supply pipe 7. Jet pump 8. Head 9. Crankshaft 11. Crank 12・ ・ Bearing 15 ・ ・ Needle bar 16 ・ ・ Oil filler 18 ・ ・ Drain pipe 22 ・ ・ Flow path 22a ・ ・ Nozzle 22b ・ ・ Diffuser part 22c ・ ・ Throat part

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kenichi Nakata 5-7-2 Sagishima, Fukushima-ku, Osaka-shi, Osaka Pegasus Sewing Machine Manufacturing Co., Ltd. F-term (reference) 3B150 AA08 CE22 GB01 GB05 GB06 GB08 3J063 AA40 BA11 BB01 CA10 CD01 XD03 XD14 XD23 XD56 XE22 XF16

Claims (2)

[Claims] An oil supply pump, an oil supply pipe connected to a discharge port of the oil supply pump, a jet pump connected to the oil supply pipe, and one end connected to the jet pump and the other end protruding from the bearing. The jet pump has a flow path composed of an upstream nozzle portion and a downstream diffuser portion connected to the nozzle portion at a throat portion, and a connection portion of the oil drain tube. A lubricating oil collecting device for a sewing machine, wherein the lubricating oil collecting device communicates with a throat side of a diffuser portion. 2. A flow path of the jet pump, wherein the nozzle portion and the diffuser portion are bent at an obtuse angle, and the angle between the diffuser portion and the nozzle portion and the diffuser portion are extended. 2. The lubricating oil collecting device for a sewing machine according to claim 1, wherein the angles formed by the connecting portions are acute.