JPH0625659U - Piston assembly jig for reciprocating engine - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to insert the piston into the cylinder accurately and quickly by fitting the piston and preventing the tilt of the piston and positioning of the piston ring. To provide something that can prevent. [Structure] A piston 2 can be fitted and a window hole 10 is formed in the top surface portion 3.
When the insertion holes 9 of the fingertips are opened on the outer peripheral wall, respectively, the small diameter portion 5 having the same diameter as the outer diameter of the piston head 2a and the large diameter portion 6 having the same diameter as the outer diameter of the piston ring 7 are coaxially provided inside. The assembling jig 1 formed on the upper surface and the inner surface of the upper surface opening 11a have the same diameter as the small diameter portion 6 of the assembling jig 1, and the lower surface opening 11 is formed.
A piston assembly jig for a reciprocating engine, characterized in that the intermediate insert 11 has a tapered inner peripheral surface having the same inner diameter as b of the cylinder.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an assembling jig used when inserting a piston having a piston ring into a cylinder of a reciprocating engine.

[0002]

[Prior art]

 Conventionally, in order to manually assemble a piston having a piston ring into a cylinder of a cylinder block, an assembly jig 1 shown in FIG. 5 is used and a work procedure shown in FIGS. 6 and 7 is performed. There is a way. That is, if the assembling jig 1 has a cylindrical shape whose upper and lower surfaces are opened in parallel, and the inner peripheral surface 2 is formed as a taper surface having a smaller diameter toward the lower side, the upper surface opening portion 1a is very small. The inner diameter of is the same as the outer diameter of the piston ring 4 of the piston 3, and the inner diameter of the lower surface opening 1b thereof is set to be the same as the inner diameter of the cylinder liner 7 fitted in the cylinder 6 of the cylinder block 5.

Therefore, first, as shown in FIG. 6, the assembling jig 1 is placed on the cylinder block 5, and the assembling jig 1 and the cylinder 6 are coaxially fixed. Next, when the piston 3 is manually pushed into the assembling jig 1 with the connecting rod 8 side down, the piston ring 4 of the piston 3 descends as shown in FIG. The taper surface gradually contracts, and the lower surface opening 1b has the same diameter as the inner diameter of the cylinder liner 7 and is inserted into the cylinder liner 7.

FIGS. 8 and 9 show another conventional assembling method, in which a pair of holders 1 has a structure in which a bent portion 3 is provided below one end of a flat plate 2, and the two holders 1 are bent. The part 3 is inserted into the gap between the inner peripheral surface of the opening of the crankcase 4 and the piston 5 to hold the piston 5, and then the cylinder 6 is fitted and fixed to the crankcase 4 (actual opening 55). -41513).

FIG. 10 shows a conventional insertion tool. The insertion tool 1 has a cylindrical shape with upper and lower surfaces opened in parallel, and the inner peripheral surface 2 is formed into a tapered surface having a smaller diameter toward the lower side. The inner peripheral surface 2 is lined with the porous metal 3, and the porous metal 3 contains the lubricating oil by the lubricating oil supply means 4. The piston assembly method using the insertion tool 1 is to mount the piston 7 on the cylinder 6 having the cylinder liner 5 in the same manner as in the first conventional example (actually published 55-112041). Issue).

[0006]

[Problems to be solved by the device]

 However, in the conventional example shown in FIG. 5 to FIG. 7, when the piston 3 is manually inserted into the assembling jig 1, if the piston 3 is tilted and inserted, the piston ring 4 is moved relative to the piston 3. Since the positions are displaced (the piston 3 and the piston ring 4 are not concentric), it becomes impossible to push them into the cylinder 6, and if they are pushed in forcefully, the piston ring 4 will be damaged. Further, this loss of the piston ring 4 cannot be found from the structural appearance, so that the performance of the engine is deteriorated.

Further, in the conventional example shown in FIG. 8 and FIG. 9, the bent portions 3 of the two holders 1 and the piston 5 are located at the opposite positions on the diameter line of the piston 5 and the inner peripheral surface of the opening of the crankcase 4. It is difficult to hold the opening of the crankcase 4 and the piston 5 coaxially because they are inserted into the gap between Therefore, there is a problem that the cylinder 6 cannot be fitted and fixed to the crankcase 4.

Further, in the conventional example shown in FIG. 10, the insertion tool 1 makes the insertion of the piston smooth by the lubricating oil contained in the porous metal 3, and at the time of insertion, in the case of the first conventional example. It has the same problem as.

[0009]

[Means for solving problems]

 The present invention has been made to solve the above-mentioned conventional problems. It is fitted to a piston to prevent the piston from tilting and to position the piston ring to prevent the piston ring from being damaged. The purpose of the invention is to provide a device that can accurately and quickly insert the piston into the cylinder to improve the efficiency of the assembling work. Although it can be fitted and a window hole is opened on the top surface and a fingertip insertion hole is opened on the outer peripheral wall, a small diameter part with the same outer diameter as the piston head and a large diameter with the same outer diameter as the piston ring are inside. Assembling jig with coaxially connecting the diameter part and the inner diameter of the upper surface opening is the same as the small diameter part of the assembly jig, and the inner diameter of the lower surface opening is the same as the inner diameter of the cylinder. And an intermediate insertion tool having a face. In the piston assembly jig professional engine.

[0010]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in FIGS. 1 is a perspective view of a piston assembling jig according to the present invention, FIG. 2 is a longitudinal sectional view of a main part of a first assembling work state by the assembling jig, and FIG. 3 is a second assembling work thereof. FIG. 4 is a vertical cross-sectional view of the main part in the state, and FIG. 4 is a vertical cross-sectional view of the main part in the third assembling work state.

In the figure, reference numeral 1 denotes an assembling jig that is fitted to the piston 2 and has a cylindrical shape having a top surface portion 3 and an opening 4 on the lower surface, and the inside thereof has a small diameter portion 5 on the top surface portion 3 side and a lower surface. It is composed of the large diameter portion 6 on the side of the opening 4, the inner diameter of the small diameter portion 5 is the same as the outer diameter of the piston head 2a of the piston 2, and the inner diameter of the large diameter portion 6 is the same as the outer diameter of the piston ring 7. It is set. The back surface of the top surface portion 3 is parallel to the lower surface of the assembling jig 1, and a flange 8 is formed on the outer periphery of the lower end of the assembling jig 1, and the outer peripheral wall on the flange 8 has fingertips at predetermined intervals. While the insertion hole 9 into which the piston 2 can be inserted is opened, the top surface portion 3 is also provided with a circular window hole 10 for pressing the piston 2.

Reference numeral 11 denotes an intermediate insertion tool interposed between the assembling jig 1 and the cylinder block 12. The intermediate insertion tool 11 has a cylindrical shape whose upper and lower surfaces are opened in parallel, and an inner peripheral surface 13 is The inner surface of the upper opening 11a of the intermediate insert 11 is the same as the outer diameter of the piston ring 7 of the piston 2, and the lower surface opening 11b of the lower opening 11b is formed. The inner diameter is set to be the same as the inner diameter of the cylinder liner 15 fitted in the cylinder 14 of the cylinder block 12.

Next, the step of inserting the piston 2 into the cylinder 14 will be described. First, as shown in FIG. 2, the intermediate insertion tool 11 is placed on the cylinder block 12, and the intermediate insertion tool 11 and The cylinder 14 and the cylinder 14 are coaxially aligned and fixed.

On the other hand, when the jig main body 1 is fitted on the piston 2 and the upper surface of the piston head 2a of the piston 2 is brought into close contact with the back surface of the top surface portion 3 of the jig main body 1, the piston head 2a becomes smaller in diameter. Since the piston 2 is coaxial with the jig body 1 to prevent inclination, the piston ring 7 is fitted to the large-diameter portion 6 so that the piston 2 is coaxial (centering function). ), The displacement of the piston ring 7 is prevented.

Therefore, the jig body 1 and the piston 2 are integrally lifted by a finger inserted into the insertion hole 9, and the lower portion of the piston 2 and the connecting rod 16 are attached to the intermediate insertion tool 11 as shown in FIG. After inserting the jig body 1, the lower surface of the jig body 1 is joined to the upper surface of the jig body 1 to fix them coaxially, and then the fingertip is pulled out from the insertion hole 9 of the jig body 1.

Then, when the piston 2 is pushed through the window hole 10 of the top surface portion 3 of the assembly jig 1, the piston 2 enters the intermediate inserter 11. Then, as shown in FIG. 4, the piston ring 7 contracts secondly as it descends due to the tapered inner peripheral surface 13 of the intermediate inserter 11, and at the lower surface opening 11 b of the intermediate inserter 11 the same as the inner diameter of the cylinder liner 15. It becomes a diameter and can be inserted into a predetermined position in the cylinder 14. If a lower surface of the jig body 1 and the upper surface of the intermediate inserter 11 and a joint surface of the lower surface of the intermediate inserter 11 and the upper surface of the cylinder 14 are provided with a fitting portion having a positioning function, they can be joined together. The person's centering becomes accurate, and the piston 2 can be inserted into the cylinder 14 accurately and quickly.

[0017]

[Effect of device]

 As described above, the piston assembly jig for a reciprocating engine according to the present invention can be fitted into a piston and has a window hole on the top surface, an outer peripheral wall and insertion holes for fingertips. An assembly jig in which a small diameter part with the same outer diameter as the head and a large diameter part with the same outer diameter as the piston ring are coaxially connected, and the inner diameter of the top opening is the smaller diameter of the assembly tool. Since it is composed of an intermediate insertion tool that has the same diameter as the part and the inner diameter of the lower surface opening is the same as the inner diameter of the cylinder, you can simply press the piston from the window hole of the jig body. It can be smoothly and quickly inserted into the cylinder. Therefore, it is possible to improve the efficiency of the assembling work and, at the same time, there are various effects that the piston ring is not damaged.

[Brief description of drawings]

FIG. 1 is a perspective view of a piston assembly jig according to the present invention.

FIG. 2 is a longitudinal sectional view of an essential part in a first assembling work state by the assembling jig.

FIG. 3 is a vertical cross-sectional view of a main part in the second assembling work state.

FIG. 4 is a vertical cross-sectional view of a main part in the third assembling work state.

FIG. 5 is a perspective view with a part of a conventional piston assembly jig removed.

FIG. 6 is a longitudinal sectional view of a main part in a first assembling work state by the assembling jig.

FIG. 7 is a vertical cross-sectional view of a main part in the second assembling work state.

FIG. 8 is a vertical sectional view showing a piston holding state by another conventional cylinder assembly piston holder.

FIG. 9 is a perspective view of the piston holder.

FIG. 10 is a vertical cross-sectional view of still another conventional piston insertion tool in an assembling work state.

[Explanation of symbols]

 1 Assembly jig 2 Piston 2a Piston head 3 Top surface part 5 Small diameter part 6 Large diameter part 7 Piston ring 9 Insertion hole 10 Window hole 11 Intermediate insertion tool 11a Upper surface opening 11b Lower surface opening 12 Cylinder block 13 Taper inner peripheral surface 14 Cylinder

Claims (1)

[Scope of utility model registration request] 1. A small hole having the same diameter as the outer diameter of the piston head and an outer portion of the piston ring can be fitted inside the piston ring by opening a window hole on the top surface and opening holes for inserting fingertips on the outer peripheral wall. Diameter of the same diameter as the diameter of the assembly jig, and the inner diameter of the upper opening is the same as the smaller diameter of the assembly jig, and the inner diameter of the lower opening is the inner diameter of the cylinder. And an intermediate insertion tool having the same tapered inner peripheral surface as that of the piston assembly jig for a reciprocating engine.