JP2515272Y2 - Plunger - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plunger of a plunger pump, and more particularly to a plunger for fixing a ceramic tip member with an adhesive.

[0002]

2. Description of the Related Art In a plunger, at least the tip is
As it is made of ceramic, it is brought into contact with chemicals in the pump chamber to improve chemical resistance and abrasion resistance.

In the conventional plunger, the ceramic part is fixed by the following structure. (A) A ceramic sleeve is fixed to the front end side of an original member with a crosshead via a bolt. (Example: Shokai 5
(Japanese Patent Laid-Open No. 5-52568) (b) A rod made of ceramic is fitted to the tip side of the original member with a crosshead, and the fitting portion is bonded with an adhesive.
(Example: Japanese Utility Model Publication No. 63-187769, Japanese Utility Model Publication 59-
No. 131501 and Japanese Utility Model Publication No. 4-15991)

[0004]

In the plunger of the structure (a), when the pump chamber has a high pressure, the sleeve is inserted from the gap between the head of the bolt fastening the ceramic sleeve to the original member and the end surface of the ceramic sleeve. The liquid easily enters the inside, and the liquid easily enters the sleeve even if the bolt is loosened due to vibration or the like.

In the plunger having the structure of (b), if the rod member on the front end side and the original member on the base end side are fixed to each other by an adhesive, it becomes difficult to separate them, and when replacing the ceramic rod member, the crankcase is used. It is difficult to simply remove the pump case from the crankcase, and the crankcase needs to be disassembled and the connecting rod needs to be removed, which makes the replacement work very complicated. Also,
When the base end portion of the ceramic rod body is fitted to the tip end portion of the original member, the air is in a sealed state inside the fitting hole and has a high pressure, which causes a large resistance to the fitting. Further, the ceramic rod on the tip side is easily removed from the original member before the adhesive is sufficiently solidified to exert the adhesive function, and the work efficiency is reduced.

The object of the invention of claim 1 is to prevent the liquid from invading the corroded portion even if the pump chamber is under high pressure or the bolt is loosened by assembling the ceramic front member by adhesion, and In a plunger capable of improving the efficiency of fixing work, it is possible to easily replace the ceramic part on the tip side without disassembling the crankcase. An object of the invention of claim 2 is to provide a plunger capable of smoothly fitting the shaft-like projection of the connecting member into the fitting hole of the ceramic tip member. It is an object of the invention of claim 3 to provide a plunger capable of improving the efficiency and accuracy of centering between the connecting member and the ceramic tip member and enhancing bending resistance. An object of the invention of claim 4 is to provide a plunger capable of obtaining a good bonding effect by restraining relative displacement of the ceramic tip member and the connecting member until the adhesive solidifies and exhibits the bonding function. Is to provide.

[0007]

The present invention will be described with reference to the reference numerals of the drawings corresponding to the embodiments. The plunger (10) of claim 1 has the following components (a) to (c). (A) A base member (12) having a crosshead (14) on the base side (b) A screw part (26) screwed to the tip of the base member (12) and a tool locking part (for locking a tool) 24) and a shaft-like protrusion (30) protruding from the tool locking portion (24) in the tip direction.
2) (c) It has a fitting hole (42) into which the shaft-like protrusion (30) is fitted, and the connecting member (50) is adhered to the shaft-like protrusion (30) in the fitting hole (42). Ceramic tip member (40) fixed to 22)

In the plunger (10) according to the second aspect, the air escape through hole (38) for connecting the tip end side of the shaft-like protrusion (30) to the peripheral portion of the tool engaging portion (24) has a connecting member (38). 22).

In the plunger (10) according to claim 3, the connecting member is provided.
(22) has an annular edge (34) that surrounds the proximal end of the axial protrusion (30) from the outside in the radial direction and forms an annular groove (36) between the proximal end and the axial protrusion (30). I have it. The annular base end portion (44) of the ceramic tip member (40) is fitted into the annular groove (36).

The plunger (10) according to claim 4 has an annular edge portion.
On the inner peripheral side of (34), the annular base end (4
A locking protrusion (46) for locking the outer peripheral side of 4) is formed.

[0011]

In the plunger (10) of claim 1, the ceramic tip member (40) is connected to the fitting hole (42) on the base end side of the connecting member (22).
The shaft-shaped protrusion (30) of the
It is fixed to the tip member by adhesion with (50). Plunger
In (10), only the ceramic tip member (40) faces the pump chamber, and the end of the ceramic tip member (40) on the proximal end side and the connecting member (22) do not enter the pump chamber. Ceramic tip member (4
(0) is replaced, the tool is locked to the tool locking portion (24) of the connection member (22), the connection member (22) is rotated, and the connection member (22) is rotated.
The screw part (26) of the above is pulled out from the tip side of the original member (12). As a result, the combined body of the connecting member (22) and the ceramic front member (40) is separated from the original member (12). Next, while rotating the combined body of the replaced new connecting member (22) and the ceramic tip member (40), while locking the tool to the tool locking portion (24) of the connecting member (22), The screw portion (26) is screwed onto the original member (12) and fixed to the original member (12).

In the plunger (10) according to claim 2, the connecting member is provided.
When the shaft-like protrusion (30) of (22) is fitted into the fitting hole (42) of the ceramic tip member (40), the air trapped deep inside the fitting hole (42) is removed from the connecting member (22). It is discharged to the outside through the air escape hole (38).

In the plunger (10) of the third aspect, the annular base end portion (44) of the ceramic tip member (40) is fitted into the annular groove (36) of the connecting member (22), respectively from the inner and outer circumferences. Axial protrusion
It is supported by the peripheral portion of (30) and the inner peripheral portion of the annular edge portion (34).

In the plunger (10) according to the fourth aspect, the annular base end portion (44) of the ceramic tip member (40) is fitted into the annular groove (36) of the connecting member (22), and the axial projection portion is formed. While waiting for the solidification of the adhesive (50) between the (30) and the insertion hole (42) of the ceramic tip member (40), the annular base end (44) is located inside the annular edge (34). It is locked by the locking projections (46) on the peripheral side.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will be described below with reference to the embodiments of the drawings. FIG. 1 is a structural diagram of the plunger 10. Plunger
10 is used as a component of a plunger pump (not shown). The base member 12 has a base end side crosshead 14 and a tip side shaft portion 16 having a smaller diameter than the crosshead 14, and the crosshead 14 is connected with a connecting rod (not shown) to form a crankshaft (see FIG. The guide of the crankcase slides back and forth in the axial direction with the rotation of (not shown). The screw hole 18 extends along the center line inside the shaft portion 16 and opens at the tip surface of the shaft portion 16.
The guide hole 20 is formed in the back of the screw hole 18 with its center line aligned with the screw hole 18, and has a smaller diameter than the screw hole 18.

The metal connecting member 22 has a hexagonal portion 24 in the axial center portion for locking and rotating the spanner. The screw portion 26 projects from the hexagonal portion 24 and is screwed into the screw hole 18. The guided shaft portion 28 further projects from the screw portion 26,
Fit into the guide hole 20. The axial projecting portion 30 having a circular cross section projects from the hexagonal portion 24 on the side opposite to the threaded portion 26, and has a plurality of annular pool portions 32 in the axial direction on the outer peripheral portion. The cylindrical guide portion 34 is formed so as to surround the radially outer side of the base end portion of the shaft-like protrusion portion 30, and forms an annular groove 36 between the cylindrical guide portion 34 and the base end portion of the shaft-like protrusion portion 30. . The air escape through-hole 38 is open at one end to the tip end surface of the shaft-shaped protrusion 30, extends along the center line in the shaft-shaped protrusion 30, and at the hexagonal portion 24 from the center of the hexagonal portion 24 to both radial directions. It branches off and opens at the periphery of the hexagonal part 24.

The ceramic tip member 40 has a cylindrical hole 42 having a diameter equal to the diameter of the shaft-shaped protruding portion 30. The cylindrical hole 42 opens on the end face of the ceramic tip member 40 on the base end side, and extends substantially along the center line of the ceramic tip member 40 by the length of the axial protrusion 30. The annular base end portion 44 defines an opening side end portion of the cylindrical hole 42 on the inside, and has a wall thickness substantially equal to the width of the annular groove 36.

FIG. 2 is an enlarged view of the area of the annular base end portion 44. An annular projection 46 is formed on the inner peripheral side of the tip end of the cylindrical guide portion 34, and is fitted into and locked in the annular locked groove 48 on the outer peripheral side of the cylindrical guide portion 34. The adhesive 50 is applied between the peripheral portion of the shaft-shaped protruding portion 30 and the wall surface of the cylindrical hole 42, and accumulates in each annular reservoir 32.

The operation of the embodiment will be described. Original member 12
The connecting member 22 is connected to the connecting member 22 before or after the connecting member 22 and the ceramic tip member 40 are connected. In the connection, the spanner is locked to the hexagonal portion 24 of the connecting member 22, the connecting member 22 is rotated, and the screw portion 26 is screwed into the screw hole 18. While the screwing is in progress, the guided shaft portion 28 is guided by the guide hole 20 and is in a fitted state, so that the original member 12 and the connecting member 22 are automatically centered.

In order to connect the connecting member 22 and the ceramic tip member 40 to each other, an adhesive 50 is applied to the peripheral portion of the axial projection 30 and / or the wall surface of the cylindrical hole 42, so that the ceramic tip member 40 is formed. The shaft-like protrusion 30 of the connecting member 22 is fitted into the cylindrical hole 42 of the. When the shaft-shaped protrusion 30 is fitted in the cylindrical hole 42, the shaft-shaped protrusion
The air trapped in the inner part of the hole 30 is a through hole for letting air out of the connecting member 22 as the shaft-shaped protruding part 30 advances to the inner part of the cylindrical hole 42.
It is released from the peripheral portion of the hexagonal portion 24 via 38. As a result, the fitting resistance of the shaft-like protrusion 30 due to the air being sealed inside the cylinder hole 42 and becoming a high pressure is avoided, and the shaft-like protrusion 30 is smoothly inserted into the cylinder hole 42.

The annular base end 44 of the ceramic tip member 40 is
While expanding the annular groove 36 of the metal connecting member 22 outward in the radial direction, the annular connecting member 22 is fitted into the annular groove 36, and is inserted into the annular engaged groove 48 on the outer peripheral portion. Is inserted into the cylindrical guide portion 34 to be in a locked state. Ceramic tip member 40
The connection member 22 is formed by fitting the shaft-shaped protrusion 30 into the cylindrical hole 42.
Centering is performed on the cylindrical guide portion 34 from the outer peripheral side of the annular base end portion 44 by fitting the annular base end portion 44 into the annular groove 36 of the connecting member 22. Make it more efficient and accurate. In addition, until the adhesive 50 is solidified and exerts a sufficient adhesive function, it is a connecting member.
The 22 and the ceramic tip member 40 are held in their relative positions by being prevented from relative displacement by the locking of the annular locked groove 48 by the annular projection 46.

The plunger 10 assembled in this way reciprocates with the rotation of the crankshaft, and the ceramic tip member.
While 40 faces the pump chamber of the plunger pump, it makes sliding contact with the packing at the peripheral portion to increase or decrease the volume of the pump chamber. The annular base end portion 44 of the ceramic tip member 40 is fitted into the annular groove 36, and is supported from the inner and outer peripheries by the peripheral surface of the base end portion of the shaft-shaped protruding portion 30 and the inner peripheral surface of the cylindrical guide portion 34. Therefore, the strength of the joint between the connecting member 22 and the ceramic front member 40 against bending stress is increased. Further, the adhesive agent 50 accumulated and solidified in each annular reservoir 32 is a ceramic tip member from the cylindrical hole 42.
A large shear resistance against the omission of 40, that is, shearing is generated, and the connection member 22 and the ceramic tip member 40 are firmly fixed.

When replacing the ceramic tip member 40, a wrench is engaged with the hexagonal portion 24 of the connecting member 22 to rotate the connecting member 22, and the screw portion 26 and the guided shaft portion 28 of the connecting member 22 are removed. It is pulled out from the screw hole 18 and the guide hole 20 of the member 12. This allows
The combination of the connecting member 22 and the ceramic tip member 40 is the original member.
Separated from 12. Next, replace the new connection member
22 and the ceramic tip member 40, the connecting member
The hexagonal portion 24 of 22 is rotated while locking the wrench, and the screw portion 26 is screwed into the screw hole 18 of the original member 12 and fixed to the original member 12.

[0024]

According to the first aspect of the present invention, the ceramic tip member is fixed to the connecting member by fitting the shaft-like protruding portion of the connecting member into the fitting hole and adhering the fitting member with an adhesive. The connecting member is configured such that the threaded portion is screwed to the tip of the original member with the crosshead. Therefore, when exchanging the ceramic tip member, it is sufficient to rotate the connecting member to pull out the threaded portion of the connecting member from the original member, and to replace the combined body of the ceramic tip member and the connecting member with a new one. By omitting the troublesome work of disassembling the connecting rod and the connecting rod, the replacement work can be simplified and streamlined.

According to the second aspect of the present invention, the connecting member has a through hole for releasing air which communicates from the tip end surface of the shaft-like protruding portion to the peripheral portion of the tool engaging portion, and the shaft-like protruding portion is fitted with the ceramic tip member. When fitting into the hole, the air left behind inside the fitting hole is released through the fitting hole. Therefore, it is possible to prevent the insertion resistance from increasing due to the high pressure of the sealed air and smoothly insert the shaft-shaped projection of the connection member into the insertion hole of the ceramic tip member.

According to the invention of claim 3, the ceramic tip member and the connecting member are properly centered by fitting the fitting hole of the ceramic tip member and the shaft-like projection of the connecting member. Since the annular base end portion of the ceramic tip member is axially fitted into the annular groove of the connecting member to add support by the inner circumference of the annular edge portion from the outer peripheral side, centering is further efficient. In addition, the bending strength of the joint between the ceramic front member and the connecting member is increased.

According to the invention of claim 4, the annular base end portion of the ceramic tip member is fitted into the annular groove of the connecting member and is engaged by the engaging protrusion of the annular edge portion of the connecting member. Until the solidification occurs, the relative displacement of the ceramic tip member and the connecting member is restricted, and the adhesive state after the solidification of the adhesive can be improved.

[Brief description of drawings]

FIG. 1 is a structural diagram of a plunger.

FIG. 2 is an enlarged view of a range of an annular base end portion.

[Explanation of symbols]

 10 Plunger 12 Base Member 14 Crosshead 22 Connection Member 24 Hexagonal Part (Tool Locking Part) 26 Screw Part 30 Shaft-shaped Projection Part 34 Cylindrical Guide Part (Annular Edge) 36 Annular Groove 38 Air Evacuation Hole 40 Ceramic Made Tip member 42 Cylindrical hole (fitting hole) 44 Annular base end portion 46 Annular projection (locking projection) 50 Adhesive

Claims (4)

(57) [Scope of utility model registration request] 1. A base member having a crosshead (14) on the base side.
(12) and a screw part (26) screwed to the tip of the original member (12).
Tool locking part (24) for locking the tool and this tool locking part (2
4) a connecting member (22) having a shaft-shaped protrusion (30) protruding in the distal direction, and a fitting hole (4) into which the shaft-shaped protrusion (30) is fitted.
2) having the shaft-like protrusion (3) in the fitting hole (42).
A ceramic tip member (40) fixed to the connecting member (22) by adhesion with the adhesive (50) to the plunger (0). 2. An air escape through hole (38) for communicating the tip end side of the shaft-like protrusion (30) with the peripheral portion of the tool engaging portion (24).
2. A plunger according to claim 1, characterized in that a recess is formed in the connection member (22). 3. The connecting member (22) includes the shaft-like protrusion (3).
The base end portion of (0) is surrounded from the outside in the radial direction, and the axial projection
An annular edge portion (34) forming an annular groove (36) with the (30) is provided, and the annular base end portion (44) of the ceramic tip member (40) is fitted into the annular groove (36). The plunger according to claim 1, wherein the plunger is fitted. 4. A locking projection (46) for locking the outer peripheral side of the annular base end (44) of the ceramic tip member (40) is formed on the inner peripheral side of the annular edge (34). The plunger according to claim 3, wherein: