JP2713062B2 - sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing machine provided with an oil supply device for supplying lubricating oil in accordance with the vertical movement of a needle.

[0002]

2. Description of the Related Art Conventionally, as a lubricating device for a sewing machine of this kind, there is a device described in, for example, Japanese Patent Publication No. 63-40225. The sewing machine body of such a sewing machine is attached to a worktable (not shown), and an oil pan (not shown) for storing the lubricating oil 10 at a lower portion of the sewing machine body.
Is arranged. As shown in FIG. 5, a pump 20 is fixed to the oil pan via a fixing member 22, and a rotor 24 of the pump 20 is connected to a well-known transmission mechanism 2.
The lubricating oil 10 is rotated in accordance with the rotation of the upper shaft 30 via the lubricating oil 6, so that the lubricating oil 10 is sucked up from the lower filter part 32 and discharged from the discharge part 34 by the stirring action. Furthermore, this discharge portion 34, one end of the oil supply pipe 36 is connected through the connector 38, whereas, the fuel supply pipe 3
The other end of the sewing machine frame 6 is cut diagonally.
It is inserted through a mounting hole 42 formed horizontally at 0.

The guide hole 44 is orthogonal to the mounting hole 42 and communicates with an upper portion thereof, and also communicates with a guide hole 50 formed in the middle metal 46 that supports the upper shaft 30. . Further, at the end of the guide hole 50 of the middle metal 46, a peeling portion 52 is formed as shown in FIGS. An injection hole 54 is formed in the upper shaft 30 facing the peeling portion 52 in the center direction of the upper shaft 30, and a center hole 56 is formed in the upper shaft 30 so as to extend in the axial direction of the upper shaft 30. The guide hole 50 communicates with the center hole 56 of the upper shaft 30 via the peeling portion 52 and the injection hole 54.

In order for the upper shaft 30 to have strength enough to withstand rotation, the inner diameter of the injection hole 54 cannot be made too large, and the inner diameter of the injection hole 54 is usually limited to about 4 mm. ing. Further, the oil supply pipe 36 is used so as not to hinder the movement of other devices inside the sewing machine, and the inner diameter of the oil supply pipe 36 is usually about 4 mm. The guide holes 44 and 50 formed in the sewing machine frame 40 and the middle metal 46 are connected to the oil supply pipe 36 and the injection hole 54.
And the flow path of the lubricating oil 10. Guide holes 44 and 50 are provided to reduce pressure loss from oil supply pipe 36 to upper shaft 30.
Has an inner diameter extending from the oil supply pipe 36 and the injection hole 54,
They have substantially the same inner diameter. The upper shaft 30 has a discharge hole 6 formed through the center hole 56 to the side surface.
0 is formed.

When the upper shaft 30 rotates to sew the work cloth, the lubricating oil 10 passes from the oil pan through the oil supply pipe 36, the guide holes 44 and 50, and the injection hole 54, and the center hole 5 of the upper shaft 30 is rotated.
Injected into 6. The lubricating oil 10 injected into the upper shaft 30
The oil is sprayed from the discharge hole 60 into the sewing machine frame 40 by the hydraulic pressure and centrifugal force of the pump 20, and supplied to the sliding portion of the drive mechanism such as the transmission mechanism 26 inside the sewing machine. The lubricating oil 10 cools the drive mechanism inside the sewing machine. In addition, in order to check whether the lubricating oil 10 is sprayed, there is a viewing window 62 in which a transparent member is fitted, and the lubricating oil 10 adheres to the inner surface of the viewing window 62 at the upper part of the sewing machine frame 40. This makes it possible to confirm that the lubricating oil 10 has been sprayed.

[0006]

However, in the conventional sewing machine, when the sewing is completed, the pump 20 is stopped along with the stop of the upper shaft 30, so that the lubricating oil 10 is supplied to the upper shaft 30.
Metal 46 and sewing machine frame 40 from center hole 56 of
The lubricating oil 10 flows backward by its own weight. At first,
Since the amount of the lubricating oil 10 is large, only the lubricating oil 10 is supplied to the guide holes 44 and 50 of the middle metal 46 and the sewing machine frame 40.
Backflow. Among them, when the amount of the backflow of the lubricating oil 10 decreases, as shown in FIG. 7, the inner diameters of the injection port 54 and the guide holes 44 and 50 are narrow, and the lubricating oil 10 has physical properties such as viscosity and surface tension. The lubricating oil 10 forms the partition 10b, and the air 71 is partitioned.

[0007] As described above, the lubricating oil 1 containing the air 71 is mixed.
0 in this mixed state, the guide holes 44 and 50 and the oil supply pipe 36
When the oil 71 flows backward through the oil supply pipe 36 in this mixed state, the air 71 collects in the casing 64 of the pump 20 shown in FIGS. Spill on bread. When sewing is resumed with the air 71 remaining inside the casing 64 of the pump 20, the portion of the rotor 24 that is in contact with the air 71 cannot stir the lubricating oil 10, so that the rotor 24 is sufficiently lubricated. The oil 10 cannot be sent and lubrication becomes insufficient. Therefore, the sliding parts may be seized or worn, or the parts may be thermally deformed due to insufficient cooling, and the drive system may not operate properly, or may generate abnormal noise. There is a problem that there is.

The first aspect of the present invention has been made to solve the above-mentioned problem, and it is possible to efficiently lubricate even if lubricating oil is mixed with air and flows backward.
And with minor changes to the conventional configuration
The present invention provides a sewing machine that can be achieved by:

Further, in the present invention, the lubricating oil is preferably air.
It is possible to efficiently lubricate
Another object of the present invention is to provide a sewing machine with reduced loss of lubricating oil feed .

[0010]

In order to achieve this object, a sewing machine according to the first aspect of the present invention has a sewing needle with an upper needle.
Can be rotated via metal to the sewing machine frame for lowering
Lubrication of the drive mechanism supported inside the sewing machine and inside the sewing machine
A central hole is formed and lubricating oil is
Upper shaft with an inlet for guiding and rotation of the upper shaft
Pump that lubricates the oil along with the
Before leading the lubricating oil discharged from the outlet to the inlet,
A guide hole formed in the metal and one end connected to the guide hole
The oil supply pipe passed through, the other end of the oil supply pipe and the front of the pump
And larger than the inner diameter of the oil supply pipe
Separates air contained in lubricating oil from lubricating oil
And an air separation chamber .

In the sewing machine according to a second aspect of the present invention, the wall of the air separation chamber on the side of the oil supply pipe is provided with an oil supply pipe.
Is formed in a tapered shape to match the inside diameter of
You.

[0012]

In the sewing machine according to the first aspect of the present invention having the above-described structure, when the sewing machine operates, lubricating oil is sent from the discharge section by the pump, and the air separation chamber and the oil supply pipe are connected.
Ru is supplied into the center hole of the upper shaft through. When the sewing machine stops, the lubricating oil containing air flows back to the pump side by its own weight, and the lubricating oil and air are separated in the air separation chamber. The lubricating oil from which air is separated reaches the inside of the pump from the discharge section, and the inside of the pump is filled only with the lubricating oil.

Further, in the sewing machine according to the second aspect of the present invention, when the upper shaft of the sewing machine rotates, the lubricating oil is discharged.
Pump from the discharge section of the pump to the air separation chamber.
Discharge from the air separation chamber along the tapered shape of the chamber wall
Is done. During delivery, pressure loss is reduced. sewing machine
Stops, the lubricating oil mixed with air is
Backflow to the pump side, lubricating oil and air are separated in the air separation chamber
Is done. Lubricating oil from which air is separated
Reach inside, pump inside is filled with lubricating oil only
You.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. The same components as those of the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the sewing machine according to the present invention, a pump 20 is disposed on the oil pan as shown in FIG.
The lubricating oil 10 in the oil pan is sucked up from the lower filter part 32 and is discharged from the discharge part 34. Further, one end of an air separation chamber 80 is connected to the discharge section 34, while one end of an oil supply pipe 36 is connected to the other end of the air separation chamber 80. The other end of the oil supply pipe 36 is cut obliquely, and is inserted into a mounting hole 42 formed horizontally in the sewing machine frame 40. The mounting hole 42, the guide holes 44, 50 and through the escaping portion 52 or the like communicates with the center hole 56 of the upper shaft 30, the lubricating oil 10 from the pump 20 into the central hole 56 of the upper shaft 30
Can be injected. The inside diameter of this oil supply pipe 36 is approximately 4
mm, which is almost the same as the inner diameter of the guide holes 44 and 50.

A cylindrical space is formed inside the air separation chamber 80. Further, the air separation chamber 80 has a feed space on the other end side (the feed direction side of the lubricating oil 10 by the pump 20). A tapered shape whose inner diameter narrows from 8 mm to 4 mm in the direction is formed. The maximum inner diameter (8 mm) of this taper is the inner diameter R1 of the columnar space of the air separation chamber 80. In other words, the air separation chamber 4
0 is formed larger than the inner diameter of the oil supply pipe 36.
I have. In order to mount the air separation chamber 80, the shape of the discharge part 34 is larger than that of the related art.
The performance of the pump 20 itself for sending the pressure is almost the same as the conventional one.

Next, the separation of the lubricating oil 10 and the air 71 in the sewing machine having the above configuration will be described.

When one process is completed during sewing, the upper shaft 3
With the stop of 0, the pump 20 stops, and the lubricating oil 10 flows backward from the center hole 56 of the upper shaft 30 to the middle metal 46 and the sewing machine frame 40 by its own weight. After a while, as shown in FIG. 7, the inner diameter of the guide holes 44 and 50 is small and the viscosity of the lubricating oil 10 (40 ° C., viscosity =
Due to physical properties such as 9.9 * 10-6 M2 / s) and surface tension, a mixed state in which the lubricating oil 10 forms the partition 10b and the air 71 is separated by the partition 10b of the lubricating oil 10. Occur. In this mixed state, the lubricating oil 10 serving as the partition 10b flows backward through the guide holes 44 and 50 and the oil supply pipe 36, and the lubricating oil 10 serving as the partition 10b flows backward through the oil supply pipe 36. To reach the air separation chamber 80.

[0019] In this way, sewing machine one Dan is stopped, 10
Seconds later, restart the sewing machine (rotation command 2000r of upper shaft 30)
pm), and an experiment for measuring the time (arrival time, unit: sec) in which the lubricating oil 10 adheres to the viewing window 62 was performed in three experiments.
Five experiments were performed on each of the three different structures. FIG. 2 shows a graph in which the arrival time is represented on the vertical axis.
Note that the same pump 20 is used in each of the structures, and the respective structures are different as described below. When the air separation chamber 80 is not used as in the past (conventional), 7 mm to 4 mm
This is the case where the air separation chamber 80 having a tapered shape that changes to 8 mm is used (Revision 1), and the case that the air separation chamber 80 that has a taper shape that changes from 8 mm to 4 mm is used (Revision 2).

According to the graph of the experimental result shown in FIG.
Compared to the conventional case where the air separation chamber 80 is not provided and the oil supply pipe 36 having an inner diameter of 4 mm is used (conventional), the case where the air separation chamber 80 is provided (revised 1 and 2) is higher. When the shaft 30 is re-rotated, the lubricating oil 10 is supplied to the viewing window 62 in a short time.
, That is, the lubricating oil 10 is quickly sent by the pump 20.

In the air separation chamber 80, the lubricating oil 10 serving as the partition 10b flows backward along the tapered wall surface of the air separation chamber 80. At this time, since the inner diameter of the air separation chamber 80 is tapered so as to be larger than the inner diameter of the oil supply pipe 36, the lubricating oil 10 serving as the partition 10b reaching the air separation chamber 80 also has The air separation chamber 80 spreads along the wall forming the taper.
As described above, when the lubricating oil 10 serving as the partition 10b spreads, the partition 1 such as the viscosity and the surface tension of the lubricating oil 10 becomes large.
0b does not endure the extent of the spread, and the partition 10b of the lubricating oil 10 bursts, and the lubricating oil 1
The droplets 0 fall into droplets, or hang down along the inner wall of the air separation chamber 80.

At this time, the air 71 is supplied to the air separation chamber 80.
As a result, the air 71 and the lubricating oil 10 are separated, so that the air 71 does not accumulate inside the casing 64 of the pump 20 and the rotor 24 does not contact the air 71. Therefore, when the upper shaft 30 rotates again, the rotor 24 immediately agitates the lubricating oil 10, the lubricating oil 10 is sent to the oil supply pipe 36, and lubrication is rapidly performed inside the sewing machine. In the air separation chamber 80, only the partition 10b of a part of the lubricating oil 10 is repelled, and the interval between the partitions 10b is simply widened. That is, even if the air 71 is merely collected, the air 71 does not accumulate inside the casing 64. Therefore, the rotor 24 and the air 71 do not come into contact with each other.

In the case of the second modification, the arrival time is shorter in the case of the second modification (the lubricating oil 10 can
If the maximum inner diameter R1 of the air separation chamber 80 is approximately 8 mm or more, the partition 10b of the lubricating oil 10 is reliably popped and the lubricating oil 10 and the air 71 are reliably separated. can do. Discharge part 34 of the pump 20
It has been found that when the inside diameter of the air separation chamber 80 is increased according to the size of the inside diameter of the air separation chamber 80, the arrival time is further reduced.

As described above, the lubrication is performed quickly, and the sliding parts of the drive mechanism are seized or worn due to insufficient lubrication, or each part is thermally deformed due to insufficient cooling. As a result, it is possible to prevent the drive system from operating properly and to prevent generation of abnormal noise. Since the air 71 and the lubricating oil 10 are separated by changing the inner diameter of the flow path of the lubricating oil 10, the air separation chamber 80 has a very simple structure and is easy to manufacture. Further, the air separation chamber 80 need only be provided in the vicinity of the discharge section 34, and since the air separation chamber 80 is small, there is no danger of contact with other mechanisms inside the sewing machine. Although the shape of the discharge section 34 is large in order to mount the air separation chamber 80, the oil separation pipe 80 and the sewing machine itself do not require a significant design change, so that it is easy to provide the air separation chamber 80.
If the shape of the protruding portion 34 is not changed, a known seal member that seals the space between the air separation chamber 80 and the discharge portion 34 may be used.

Since the shape of the air separation chamber 80 is narrowed with respect to the feed direction of the lubricating oil 10 of the pump 20,
The feed loss of the lubricating oil 10 is reduced. When the stop and rotation of the upper shaft 30 of the sewing machine are frequently repeated during the sewing operation, the pump 20 using the rotation of the upper shaft 30 stops and operates according to the stop and rotation of the upper shaft 30. Therefore, in the pump 20 of the sewing machine, the backflow of the lubricating oil 10 occurs every time the upper shaft 30 is stopped.
It is particularly desirable to separate 0 and air 71. When the rotation speed of the rotor 24 is low, the rotor 24 can only agitate the lubricating oil 10, but when the rotation speed of the rotor 24 is higher than a certain rotation speed, the rotor 24 also stirs the air 71. By rotating as described above, the pump 20 can send the lubricating oil 10 together with the air 71. When the experiment is performed by setting various rotation instructions of the upper shaft 30 among the experimental conditions, the rotation instruction of the upper shaft 30 is high (3000 rpm or more: 3000 rpm is a substantially intermediate value of the maximum rotation speed). When the rotation command of the upper shaft 30 is lower (3000 rpm or less) than in the case, the difference in arrival time due to the difference in the structure (the presence or absence of the air separation chamber 80) is larger. In other words, the lower the rotation command of the upper shaft 30 is, the more remarkable the effect of using the air separation chamber 80 is. It should be noted that the present invention is not limited only to the above-described embodiment, and various modifications can be made only without departing from the gist of the present invention.

For example, when there is room in the internal space of the sewing machine, as shown in FIGS.
The oil supply pipe 92 having a diameter of at least m is used, and the oil supply pipe 92 can be attached to the sewing machine frame 40.
4 is formed horizontally, and an oil supply pipe 92 is attached to the attachment hole 94. Also, the sewing machine frame 40 and the middle metal 4
6, guide holes 96 and 98 having the same inner diameter as the oil supply pipe 92.
Are formed so as to be substantially orthogonal to the mounting hole 94, and the peeling portion 100 is formed deeper than in the prior art. In this case, the difference between the inner diameter of the injection hole 54 and the guide holes 96 and 98 (the inner diameter of the injection hole 54 <the inner diameter of the guide holes 96 and 98) is used at the portion of the guide hole 50 that communicates with the peeling portion 100. The air 71 may be separated from the lubricating oil 10. That is, the communicating portion of the guide hole 50 with the peeling portion 100 is the air separation chamber 80.
And the lubricating oil 10 is quickly sent by the pump 20, and there is no need to provide a new part (the air separation chamber 80). The oil supply pipe 92 has a substantially uniform thickness so that the oil supply pipe 92 also functions as the air separation chamber 80. One end of the oil supply pipe 92 is attached to the discharge section 34 of the pump 20. Is attached to the mounting hole 42.

[0027]

As is apparent from the above description, in the sewing machine according to the first aspect of the present invention, the air is separated from the lubricating oil in the air chamber, and no air is accumulated inside the pump. , The pump sends the lubricating oil efficiently. Therefore, due to insufficient lubrication, the sliding part of the drive mechanism is seized, worn, and each part is thermally deformed due to insufficient cooling, and the drive system does not operate properly, or The generation of abnormal noise is prevented. Moreover, the discharge of the pump
Between the oil pipe and the oil supply pipe
It only needs to provide an air separation chamber with a diameter.
The configuration of the device is simple, and the configuration is simple.
Conversion is easy.

In the sewing machine according to the second aspect of the present invention, the wall surface of the air separation chamber in the lubricating oil feed direction is tapered.
-Guides the lubricating oil sent by the pump according to the shape
The air contained in the lubricating oil separates from the lubricating oil
And the pressure loss in the air separation chamber is reduced.
The pump sends the lubricating oil efficiently. Therefore, lubrication is quick
This can cause seizure, wear, thermal deformation or noise
Is prevented.

[Brief description of the drawings]

FIG. 1 is an overall view of an embodiment embodying the present invention.

FIG. 2 is a diagram showing experimental results.

FIG. 3 is an overall view of an embodiment embodying the present invention.

FIG. 4 is an enlarged view of an embodiment embodying the present invention.

FIG. 5 is an overall view of a conventional technique.

FIG. 6 is an explanatory diagram showing a support state of an upper shaft.

FIG. 7 is an explanatory diagram showing a mixed state of air and lubricating oil.

FIG. 8 is a cross-sectional bottom view of the pump.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Lubricating oil 20 Pump 24 Rotor 30 Upper shaft 34 Discharge part 36 Oil supply pipe 42 Mounting hole 44,50 Guide hole 80 Air separation chamber

Claims (2)

(57) [Claims] A sewing machine for moving a sewing needle up and down.
Is rotatably supported via metal to the sewing machine and inside the sewing machine.
When the central hole is formed for lubrication of the drive mechanism in the section
Both are formed with an inlet to guide lubricating oil to its central hole
An upper shaft, a pump for flowing lubricating oil along with the rotation of the upper shaft, and a lubricating oil discharged from a discharge portion of the pump.
A guide hole formed in the metal for guiding the oil supply, an oil supply pipe having one end communicating with the guide hole, and an oil supply pipe provided between the other end of the oil supply pipe and the discharge section of the pump.
Lubricating oil having an inside diameter larger than the inside diameter of the oil supply pipe
An air separation chamber for separating air contained therein from lubricating oil . 2. The wall surface of the air separation chamber on the side of the oil supply pipe.
Is tapered to match the inside diameter of the oil supply pipe
Sewing machine according to claim 1, characterized in that it is formed.