JP3226903U - Sleeve end - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sleeve end portion capable of easily holding a lubricant in a groove of an inner peripheral surface.
SOLUTION: A pouring port 13 of a sleeve 10 is formed in a tubular shape around an axis C intersecting with the vertical direction, a first end side in the axial direction is attached to a mold, and a plunger tip 4 slides inside the sleeve 10. The annular sleeve end portion 20 that is located closer to the second end 12 in the axial direction than the second end 12 and forms the second end has a groove 30 that is continuous over the entire circumference of the inner peripheral surface 21 of the sleeve end portion. An inlet passage 24 connected to the upper end portion and opening to the outer peripheral surface 22 or the second end of the sleeve end portion, and an outlet passage 25 connected to the lower end portion of the groove and opened to the outer peripheral surface or the second end are provided. A holding surface 36 that includes a groove end surface 33 that extends radially outward from the peripheral surface and faces the second end side and that extends from the lower end edge 33b of the groove end surface to the second end side is formed at the connecting portion between the discharge path and the groove. Has been done.
[Selection diagram] Figure 1

Description

The present invention relates to an end portion of a sleeve in which a groove for distributing a lubricant is formed on an outer peripheral surface of a plunger tip on an inner peripheral surface.

In an injection device for injecting a molten metal into a cavity of a mold, a sleeve formed in a tubular shape around a substantially horizontal axis and having a first end side in the axial direction attached to the mold slides in the sleeve. Some have a plunger tip. A flow path for feeding the lubricant to the outer peripheral surface of the plunger tip is formed at the end of the sleeve on the second end side in the axial direction with respect to the pouring port. The flow path disclosed in Patent Document 1 is a groove formed on an inner peripheral surface of a sleeve so as to connect the supply port and the discharge port, which penetrate the upper part and the lower part of the sleeve in the radial direction, and the supply port and the discharge port. And are equipped with. By sending the lubricant from the supply port to the groove and causing the lubricant in the groove to adhere to the outer peripheral surface of the plunger tip, the inner peripheral surface of the sleeve is less likely to be damaged.

Japanese Patent Laid-Open No. 11-77274

However, in the end portion of the sleeve disclosed in Patent Document 1, the discharge port extends directly below the groove, so that the lubricant in the groove easily flows out from the discharge port, and it is difficult to retain the lubricant in the groove. .. Therefore, if the timing of injecting the molten metal after the lubricant is supplied to the groove is delayed, the lubricant adhering to the outer peripheral surface of the plunger tip flows and decreases, and the inner peripheral surface of the sleeve may be damaged. If it is difficult to retain the lubricant in the groove, in order to inject the molten metal with the lubricant sufficiently attached to the outer peripheral surface of the plunger tip, supply a large amount of lubricant to the groove each time immediately before the injection. There is a need to.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a sleeve end portion that can easily hold a lubricant in a groove of an inner peripheral surface.

To achieve this object, the sleeve end portion of the present invention is formed in a tubular shape centering on an axis intersecting with the vertical direction, the first end side in the axial direction is attached to the mold, and the plunger tip slides inside. Of the sleeve, which is an annular portion that is located closer to the second end side in the axial direction than the pouring port and forms the second end, and is continuous over the entire circumference of the inner peripheral surface of the sleeve end portion. Groove, an introduction path connected to the upper end of the groove and opened to the outer peripheral surface of the sleeve end or the second end, and a discharge path connected to the lower end of the groove and opened to the outer peripheral surface or the second end. And the groove includes a groove end surface that extends radially outward from the inner peripheral surface and faces the second end side, and a lower end of the groove end surface is provided at a connection portion between the discharge path and the groove. A holding surface extending from the edge toward the second end is formed.

According to the sleeve end portion of the first aspect, the plunger tip covers the groove that is continuous over the entire inner peripheral surface of the sleeve end portion, and opens in the outer peripheral surface or the second end of the sleeve end portion. Lubricant is supplied from the introduction path to the upper end of the groove. Since the discharge passage connected to the lower end of the groove is opened to the outer peripheral surface of the sleeve end or the second end, the lubricant supplied from the introduction passage flows through the groove while the air in the groove escapes from the discharge passage. Go A holding surface that extends from the lower end edge of the groove end surface of the groove to the second end side is formed at the connecting portion between the discharge path and the groove. As a result, the amount of lubricant discharged in the groove can be reduced and the lubricant can be easily retained in the groove, as compared with the case where the discharge path extends directly below the groove end surface.

According to the sleeve end of the second aspect, the discharge passage is a groove that opens at the second end. As a result, the plunger tip slides through the upper opening of the discharge path when the plunger tip retracts toward the second end side. As a result, it is possible to discharge the burr scraped off on the groove end surface during the advance of the plunger tip toward the first end side and the excess lubricant so as to be scraped out from the discharge path as the plunger tip retracts. Therefore, it is possible to prevent the groove from being clogged with burrs and obstructing the flow of the lubricant. Therefore, in addition to the effect of the first aspect, it is possible to easily spread the lubricant to the outer peripheral surface of the groove and the plunger tip.

According to the sleeve end portion of the third aspect, the inclined surface of the groove connects the radially outer peripheral edge of the groove end surface and the inner peripheral surface, and inclines toward the axial line side from the groove end surface toward the second end side. .. This makes it possible to widen the first end side of the groove while reducing the channel cross-sectional area of the groove. The smaller the channel cross-sectional area of the groove, the easier it is to hold the lubricant in the groove due to the surface tension of the lubricant or the like. Further, since the first end side of the groove is wide, the lubricant can be easily attached to the outer peripheral surface of the plunger tip when the plunger tip advances toward the first end side. As a result, in addition to the effect of claim 1 or 2, the lubricant can be more easily spread over the outer peripheral surface of the plunger tip.

Further, since the corner where the inclined surface and the groove end surface intersect is chamfered, it is possible to make it difficult for the burr to be caught in the corner. Further, the inclined surface connected to the inner peripheral surface of the sleeve end portion makes it easier to discharge the burr from the groove to the second end side when the plunger tip retracts. In particular, since the corner where the inclined surface and the inner peripheral surface of the sleeve end intersect is chamfered, it is possible to more easily discharge the burr from the groove to the second end side when the plunger tip retracts.

FIG. 6 is a cross-sectional view of an injection device having a sleeve end in one embodiment. 1A is a cross-sectional view of the injection device taken along line IIa-IIa in FIG. 1, and FIG. 1B is a cross-sectional view of the injection device taken along line IIb-IIb in FIG.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The injection device 1 will be described with reference to FIGS. 1 to 2B. FIG. 1 is a cross-sectional view of an injection device 1 having a sleeve end 20 according to one embodiment. 2A is a cross-sectional view of the injection device 1 taken along the line IIa-IIa in FIG. 2B is a cross-sectional view of the injection device 1 taken along the line IIb-IIb in FIG. The directions of arrows U, D, F, B, L, and R on the drawings indicate the upper side, the lower side, the front side, the rear side, the left side, and the right side of the injection device 1, respectively. The front-rear direction and the left-right direction are horizontal. FIG. 1 is an enlarged view of the vicinity of the pouring port 13 of the injection device 1.

As shown in FIG. 1, the injection device 1 is a device for injecting molten metal into a cavity of a mold (not shown). The injection device 1 includes a substantially cylindrical sleeve 10 centered on a substantially horizontal axis C that intersects the vertical direction, and a substantially cylindrical plunger tip 4 (hereinafter, referred to as “tip 4”) that slides in the sleeve 10. , A plunger rod 5 to which the tip 4 is fixed (hereinafter referred to as “rod 5”). The axis C direction is the front-back direction. Further, the cross-sectional view of FIG. 1 shows a cross section of the injection device 1 including the axis C.

The tip 4 is a member that pushes the molten metal injected into the sleeve 10 toward the cavity side. The rod 5 is a rod-shaped member that advances and retracts in the direction of the axis C from an injection cylinder (not shown). The tip of the rod 5 (the end on the left side of the paper surface of FIG. 1) separated from the injection cylinder is fixed to the tip 4. As the rod 5 advances and retracts, the tip 4 slides on the sleeve 10 in the direction of the axis C.

The cylindrical sleeve 10 has a first end side in the axis C direction (front side, left side in FIG. 1 paper) attached to a mold, and a second end 12 in the axis C direction (rear end, end portion on the right side in FIG. 1 paper). Is open. A pouring port 13 is formed in the sleeve 10 so as to radially pass through an upper portion near the second end 12.

The sleeve 10 includes an annular sleeve end portion 20 that is located closer to the second end 12 side than the pouring port 13 and forms the second end 12, and a sleeve body 14 in which the pouring port 13 is formed and fixed to a mold. , Are provided. In the present embodiment, the sleeve end portion 20 and the sleeve body 14 are formed by separate members and are connected to each other by screws (not shown) or the like.

The inner peripheral surface 15 of the sleeve body 14 and the inner peripheral surface 21 of the sleeve end portion 20 are formed parallel to the axis C in a cross section including the axis C. The inner diameters of the sleeve body 14 and the sleeve end portion 20 are the same as each other, and are substantially the same as the outer diameter of the tip 4. Therefore, the tip 4 slides in the sleeve body 14 and the sleeve end portion 20 while the outer peripheral surface of the tip 4 is in close contact with the inner peripheral surface 15 and the inner peripheral surface 21 over the entire circumference.

In order to inject the molten metal with the injection device 1, first, the tip 4 is retracted to the standby position on the second end 12 side of the pouring port 13 so that the tip 4 is positioned inside the sleeve end portion 20. In this state, the molten metal is injected from the pouring port 13 into the sleeve body 14. After that, by moving the tip 4 forward toward the first end, the molten metal in the sleeve body 14 is pushed by the tip 4 and injected into the cavity.

In order to make the inner peripheral surfaces 15 and 21 of the sleeve 10 and the outer peripheral surface of the chip 4 slippery, a liquid lubricant is applied to the outer peripheral surface of the chip 4. By attaching an appropriate amount of lubricant to the outer peripheral surface of the chip 4, so-called chip galling can be made less likely to occur, and the inner peripheral surfaces 15 and 21 of the sleeve 10 and the chip 4 can be less likely to be damaged. A flow path is formed in the sleeve end portion 20 to distribute the lubricant to the outer peripheral surface of the chip 4. As a flow path for the lubricant, the sleeve end 20 has a groove 30 that is continuous over the entire circumference of the inner peripheral surface 21, and is connected to the upper end of the groove 30 and opens to the outer peripheral surface 22 of the sleeve end 20. A passage 24 and a discharge passage 25 connected to the lower end of the groove 30 and opening to the second end 12 are formed.

As shown in FIGS. 1 and 2A, the introduction path 24 is a hole that penetrates the upper portion of the sleeve end portion 20 in the vertical direction (radial direction). A supply pipe 26 is connected to the opening of the outer peripheral surface 22 of the introduction path 24. By a control device (not shown), the lubricant is fed from the supply pipe 26 to the introduction passage 24 in a state where the tip 4 is located in the sleeve end portion 20 every time the molten metal is injected by the injection device 1 or every time the injection is performed a plurality of times. Dropped and supplied.

The discharge passage 25 is a groove that opens to the second end 12, and is formed in the inner peripheral surface 21 in a straight line along the axis C. The discharge path 25 is located at the lowermost end of the inner peripheral surface 21. The discharge passage 25 is located symmetrically to the introduction passage 24 with respect to the axis C. The depth from the inner peripheral surface 21 to the bottom surface of the discharge passage 25 is substantially constant along the axis C direction. Note that this depth may be changed in the direction of the axis C.

The groove 30 includes an open groove portion 31 to which the introduction passage 24 is connected, and a closed groove portion 32 to connect the open groove portion 31 and the discharge passage 25. The open groove portion 31 and the closed groove portion 32 include a groove end surface 33 that extends radially outward from the inner peripheral surface 21 and faces the second end 12 side. The groove end surface 33 is formed perpendicular to the axis C and the inner peripheral surface 21. By the corner between the groove end surface 33 and the inner peripheral surface 21, burrs adhering to the outer peripheral surface of the chip 4 during the previous casting can be scraped off as the chip 4 advances.

The open groove portion 31 is a portion in a predetermined range on the upper side of the groove 30. It is preferable that the open groove portion 31 be within a range of 45° from the upper end portion of the groove 30 to the left and right with the axis C as the center. The open groove portion 31 includes a groove bottom surface 34 extending from the radially outer peripheral edge 33a of the groove end surface 33 toward the second end 12 side. The groove bottom surface 34 is formed substantially parallel to the axis C in a cross section including the axis C, and is formed up to the second end 12. That is, the open groove portion 31 opens at the second end 12. This makes it possible to visually confirm that the lubricant is supplied from the introduction path 24 to the groove 30 from the second end 12 side through the groove portion 31.

As shown in FIG. 1, FIG. 2A, and FIG. 2B, the closed groove portion 32 is closed by the chip 4 to form a closed channel extending in the circumferential direction. The closed groove portion 32 is formed substantially uniformly in the circumferential direction. Therefore, the flow passage cross-sectional area when the closed groove portion 32 is closed by the chip 4 becomes substantially constant. The flow passage cross-sectional area of the closed groove portion 32 is larger than the flow passage cross-sectional area when the discharge passage 25 is blocked by the chip 4.

The closed groove portion 32 includes an inclined surface 35 that connects the peripheral edge 33 a of the groove end surface 33 and the inner peripheral surface 21. The inclined surface 35 inclines toward the axis C side from the groove end surface 33 toward the second end 12 side. The corners where the inclined surface 35 and the groove end surface 33 intersect are chamfered, and the corners where the inclined surface 35 and the inner peripheral surface 21 intersect are chamfered. Both chamfers are R chamfers formed by a curved surface that smoothly connects two surfaces.

At the lower end of the groove 30 (closed groove portion 32) and at the connecting portion between the discharge passage 25 and the groove 30, the discharge passage 25 is open above the inclined surface 35. A part of the inclined surface 35 at the connection portion between the discharge path 25 and the groove 30 is a holding surface 36 that extends from the lower end edge 33b of the peripheral edge 33a of the groove end surface 33 toward the second end 12 side. The lower end of the holding surface 36 is located below the bottom surface of the discharge path 25.

According to the injection device 1 having the sleeve end 20 as described above, the tip 4 is retracted to the standby position closer to the second end 12 than the pouring port 13 and the groove 4 is covered with the tip 4 in the supply pipe. The lubricant is supplied from 26 to the upper end of the groove 30 through the introduction passage 24. Since the discharge passage 25 connected to the lower end portion of the groove 30 opens at the second end 12 of the sleeve end portion 20, if the lubricant is supplied to the groove 30 with almost no lubricant in the groove 30, the inside of the groove 30 The lubricant flows downward in the groove 30 while the air of the above is discharged from the discharge passage 25. Since the holding surface 36 that extends from the lower end edge 33b of the groove end surface 33 to the second end 12 side is provided at the connecting portion between the discharge path 25 and the groove 30, as compared with the case where the discharge path extends directly below the groove end surface 33. Therefore, the discharge amount of the lubricant in the groove 30 can be reduced, and the lubricant can be easily retained in the groove 30.

As a result, the lubricant retained in the groove 30 can be sufficiently adhered to the outer peripheral surface of the tip 4, so that chip galling can be less likely to occur and the inner peripheral surfaces 15 and 21 of the sleeve 10 can be less likely to be damaged. .. In addition, since the lubricant is likely to remain in the groove 30 after the molten metal is injected by the holding surface 36, the amount of the lubricant supplied to the groove 30 before the injection can be reduced.

The closed groove portion 32 of the groove 30 is closed by the chip 4 to form a closed flow path extending in the circumferential direction. By reducing the discharge amount of the lubricant in the closed groove portion 32, the lubricant can be easily accumulated in the closed groove portion 32, and the lubricant can be easily attached to the outer peripheral surface of the chip. Further, the outer peripheral surface of the chip 4 facing the open groove portion 31 provided within the range of 45° from the upper end portion of the groove 30 has a gentle descending inclination. Therefore, even if the open groove portion 31 is wide and opens at the second end 12, it is difficult for the lubricant supplied to the open groove portion 31 and riding on the outer peripheral surface of the chip 4 to flow downward. Therefore, the lubricant in the groove 31 can be easily left on the outer peripheral surface of the chip 4. As a result, it is possible to easily maintain the state where the lubricant is attached to the outer peripheral surface of the chip 4, and it is possible to easily spread the lubricant to the outer peripheral surface of the chip 4.

Further, the flow channel cross-sectional area of the closed groove portion 32 blocked by the chip 4 is larger than the flow channel cross-sectional area of the discharge passage 25 blocked by the chip 4. As a result, the hydraulic pressure of the lubricant in the discharge passage 25 becomes greater than the hydraulic pressure of the lubricant in the closed groove portion 32, and the lubricant cannot flow out easily from the discharge passage 25. In particular, since the flow paths of the closed groove portions 32 on both the left and right sides merge and flow to the discharge path 25, it becomes more difficult for the lubricant to flow out from the discharge path 25. Further, the bottom surface of the discharge passage 25 is above the lower end portion of the holding surface 36. Therefore, in order for the lubricant to flow from the closed groove portion 32 to the discharge passage 25, a force counter to the gravity direction is required, and the lubricant is more difficult to flow out from the discharge passage 25. As a result, the lubricant is likely to remain in the closed groove portion 32, so that the lubricant can be more easily spread on the outer peripheral surface of the chip 4.

The inclined surface 35 that connects the peripheral edge 33a of the groove end surface 33 and the inner peripheral surface 21 inclines toward the axis C side from the groove end surface 33 toward the second end 12 side. This makes it possible to widen the first end side (the groove end face 33 side) of the groove 30 while reducing the flow passage cross-sectional area of the groove 30. The smaller the channel cross-sectional area of the groove 30, the easier it becomes to hold the lubricant in the groove 30 due to the surface tension of the lubricant or the like. Moreover, since the first end side of the groove 30 is wide, it is possible to easily adhere the lubricant to the outer peripheral surface of the chip 4 when the tip 4 advances toward the first end side. As a result, the lubricant can be more easily spread over the outer peripheral surface of the chip 4.

Burrs adhering to the outer peripheral surface of the tip 4 during the previous casting are scraped off by the groove end surface 33 as the tip 4 advances. The burr flows downward in the groove 30 together with the lubricant and is discharged to the outside from the discharge passage 25. Since the corner where the inclined surface 35 and the groove end surface 33 intersect is chamfered and the corner is not tapered, it is difficult to pinch the burr in the corner, and the burr can easily flow together with the lubricant. As described above, by discharging the burr from the groove 30, it is possible to prevent the groove 30 from being clogged with the burr and obstructing the flow of the lubricant. As a result, the lubricant can be easily spread over the groove 30 and the outer peripheral surface of the chip 4.

The discharge path 25 is a groove formed in the lower portion of the inner peripheral surface 21 and opening to the second end 12. As a result, when the chip 4 retreats after the molten metal is injected, the chip 4 slides through the upper opening of the discharge passage 25. Therefore, burrs and excess lubricant can be discharged so as to be scraped out from the discharge path 25 as the tip 4 moves backward. Further, since the discharge passage 25 is formed in a straight line along the axis C, it is possible to easily discharge burrs and excess lubricant from the discharge passage 25 as the tip 4 retreats. As a result, it is possible to further prevent the groove 30 from being clogged with burrs and obstructing the flow of the lubricant, and it is possible to more easily spread the lubricant to the groove 30 and the outer peripheral surface of the chip 4.

Since the inclined surface 35 that inclines toward the axis C from the groove end surface 33 toward the second end 12 side is connected to the inner peripheral surface 21 of the sleeve end portion 20, it follows the inclination from the groove 30 when the chip 4 retracts. The burr can be easily discharged to the second end 12 side. At this time, even if a small burr coming out of the groove 30 is sandwiched between the outer peripheral surface and the inner peripheral surface 21 of the chip 4, the burr gradually flows by gravity to the discharge path 25 having an upper opening. The burr can be discharged from the discharge passage 25 to the outside.

Since the corner where the inclined surface 35 and the inner peripheral surface 21 intersect is chamfered, it is possible to make it difficult for the burr to be caught at the corner and to easily discharge the burr from the groove 30 toward the second end 12 side when the chip 4 retracts. it can. In particular, since the corner between the inclined surface 35 and the inner peripheral surface 21 is rounded, the burr is less likely to be caught at the corner, and the burr can be more easily discharged from the groove 30 when the chip 4 is retracted.

The present invention has been described above based on the embodiment. However, the present invention is not limited to the above-described embodiment, and it is easily inferred that various improvements and modifications can be made without departing from the spirit of the present invention. It is possible. For example, the size and shape of each part of the chip 4 and the sleeve 10 may be changed appropriately. The sleeve 10 may be formed in an elliptic cylinder shape or a rectangular cylinder shape, and the chip 4 may be formed in an elliptic cylinder shape or a prism shape. The axis C may be tilted from the horizontal plane.

In the above embodiment, the case where the sleeve end 20 and the sleeve body 14 which are separate members are connected to each other to form the sleeve 10 has been described, but the present invention is not limited to this. The sleeve end 20 and the sleeve body 14 may be integrally formed. Further, the sleeve body 14 may be divided into a plurality of pieces in the direction of the axis C.

In the above embodiment, the case where the discharge path 25 opening to the second end 12 is the groove formed on the inner peripheral surface 21 of the sleeve end portion 20 has been described, but the present invention is not limited to this. A discharge passage may be formed to penetrate the sleeve end 20 in the radial direction, and the discharge passage may be opened to the outer peripheral surface 22. Also in this case, the discharge path is separated from the groove end surface 33 in the direction of the axis C, and a holding surface 36 extending from the lower end edge 33b of the groove end surface 33 to the second end 12 side is provided at the connection portion between the discharge path and the groove 30. .. The discharge passage that penetrates the sleeve end portion 20 in the radial direction may be formed perpendicularly to the axis C or may be formed non-perpendicularly to the axis C.

In the above embodiment, the case where the discharge passage 25 opens above the inclined surface 35 at the connection portion between the discharge passage 25 and the groove 30 has been described, but the present invention is not limited to this. The discharge path 25 may be opened over the entire inclined surface 35 at the connecting portion between the discharge path 25 and the groove 30 to form the discharge path 25 extending from the groove end surface 33 to the second end 12 side. In this case, the bottom surface of the discharge path 25 extending to the second end 12 side serves as a holding surface extending from the lower end edge 33b of the groove end surface 33 to the second end 12 side.

In the above embodiment, the case where the groove 30 includes the open groove portion 31 and the closed groove portion 32 has been described, but the present invention is not limited to this. The open groove portion 31 that opens to the second end 12 may be omitted, and the groove 30 may be formed by the closed groove portion 32 over the entire circumference. As a result, the groove 30 blocked by the chip 4 forms a closed flow path over the entire circumference, and the lubricant can be easily retained in the groove 30.

Not only when the groove end surface 33 is perpendicular to the axis C and the inner peripheral surface 21, that is, when the angle between the inner peripheral surface 21 and the groove end surface 33 is about 90°, the inner peripheral surface 21 and the groove end surface 33 The angle formed by may be other than 90°. If the angle formed by the inner peripheral surface 21 and the groove end surface 33 is 90° or less, the burr can be easily scraped off by the groove end surface 33 when the chip 4 advances. If the angle is 90° or more, the groove end face 33 can be easily formed. By setting the angle to about 90°, burrs can be easily scraped off by the groove end surface 33 when the chip 4 is advanced, and the groove end surface 33 can be easily formed.

Further, the bottom surface extending from the groove end surface 33 to the second end 12 side is not limited to the case where the groove end surface 33 of the closed groove portion 32 and the inner peripheral surface 21 of the sleeve end portion 20 are connected by the inclined surface 35. It may be formed parallel to the axis C in the included cross section, or may be inclined toward the side opposite to the axis C as it goes away from the groove end face 33. The edge on the second end 12 side of the bottom surface and the inner peripheral surface 21 may be connected by a wall surface substantially perpendicular to the inner peripheral surface 21 or may be connected by the inclined surface 35. Further, the discharge path 25 opening to the second end 12 or the outer peripheral surface 22 may be connected to such a bottom surface or wall surface.

Although the case where the introduction path 24 connected to the groove 30 opens in the outer peripheral surface 22 of the sleeve end portion 20 has been described in the above embodiment, the present invention is not limited to this. The introduction passage 24 may be opened to the second end 12 of the sleeve end portion 20. For example, a part of the open groove portion 31 in the above embodiment is used as an introduction path, and a thin supply pipe is inserted into the introduction path so as not to hit the chip 4. By supplying the lubricant from the supply pipe to the upper end of the groove 30, the lubricant flows in the groove 30. Further, a hole formed between the inner peripheral surface 21 and the outer peripheral surface 22 of the sleeve end portion 20 and opening to the second end 12 may be used as the introduction path.

In the above embodiment, the case where the lubricant is dripped from the supply pipe 26 to the introduction passage 24 has been described, but the present invention is not limited to this. The lubricant may be supplied from the supply pipe 26 to the introduction path 24 at a predetermined pressure. Further, after the lubricant is supplied from the supply pipe 26 to the introduction passage 24, air may be sent to the introduction passage 24 to spread the lubricant in the groove 30.

In the above embodiment, the case where the corners where the inclined surface 35 and the groove end surface 33 intersect and the corners where the inclined surface 35 and the inner peripheral surface 21 intersect each other are R-chamfered have been described, but the invention is not limited thereto. Not a thing. The chamfering of the corner between the inclined surface 35 and the groove end surface 33 or the chamfering of the corner between the inclined surface 35 and the inner peripheral surface 21 is performed by connecting the two surfaces with one or more surfaces having a straight section including the axis C. You may form so.

4 Plunger tip 10 Sleeve 12 Second end 13 Pouring port 20 Sleeve end 21 Inner peripheral surface 22 Outer peripheral surface 24 Introducing path 25 Discharging path 30 Groove 33 Groove end surface 33a Perimeter 33b Lower edge 35 Sloping surface 36 Holding surface C axis

Claims (3)

Of the sleeve formed in a tubular shape centering on an axis intersecting with the vertical direction and having the first end side in the axial direction attached to the mold and the plunger tip sliding inside, the second one in the axial direction rather than the pouring port An annular sleeve end located on the end side and forming the second end,
A groove that is continuous over the entire circumference of the inner peripheral surface of the sleeve end,
An introduction path connected to the upper end of the groove and opening to the outer peripheral surface of the sleeve end or the second end;
A discharge path connected to the lower end of the groove and opening to the outer peripheral surface or the second end,
The groove includes a groove end surface that extends radially outward from the inner peripheral surface and faces the second end side,
A sleeve end portion, wherein a holding surface extending from a lower end edge of the groove end surface to the second end side is formed at a connecting portion between the discharge path and the groove. The sleeve end portion according to claim 1, wherein the discharge path is a groove that opens to the second end. The groove includes an inclined surface that connects the radially outer peripheral edge of the groove end surface and the inner peripheral surface, and that is inclined toward the axial line side from the groove end surface toward the second end side,
The sleeve according to claim 1 or 2, wherein a corner where the inclined surface and the groove end surface intersect is chamfered, and a corner where the inclined surface and the inner peripheral surface intersect is chamfered. edge.

Images