JPH0989048A - Manufacture of case for viscous damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a cost of manufacture such as a cost of material, cost of working, etc., so that a product can be inexpensively prepared, by welding one end surface of a large diametric part of a steel pipe to one end surface of a joint having a small diametric part, and preparing an inertia ring, plurality of bearings and an annular recessed part for sealing a viscous fluid. SOLUTION: First, after a seam welded steel pipe is cut into a prescribed length, its one end surface 10A is cut, a stepped part is prepared in the inside of the other end surface 10A, and a large diametric part 10 is prepared. A joint is formed by forging into an integral constitution, but a tapered hole, mounting cavity and a part forming a cavity part are provided. Each part of this joint is accurately cut, a joint 12 is formed which has a tapered hole 12A, mounting cavity 12B, screw hole 12C and a cavity part 12D. One end part 10A of the large diametric part 10 is piled together in an end surf ace 12D1 of the cavity part 12d in the joint 12, welding 13 is performed, so that a case for a viscous damper can be prepared.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a viscous damper case which can be manufactured at low cost.

[0002]

2. Description of the Related Art In recent years, exhaust gas regulations have been tightened in diesel engines, and in response to this, it has been proposed to promote atomization of fuel in order to improve the fuel efficiency of diesel engines. Therefore, in the fuel injection pump, the injection pressure of fuel tends to be increased. However, when the injection pressure is increased, there is a problem that the torsional vibration and torque fluctuation width of the drive system of the fuel injection pump increase, and the gear noise of the fuel injection pump drive gear is generated. A viscous damper is used to reduce it.

FIG. 5 is a sectional view showing a conventional viscous damper. FIG. 6 is a plan view and a cross-sectional view taken along line A1-A2 of the case before cutting, which is created by forging. In the figure, 1 is a case before cutting, and this case 1 comprises an outer cylinder portion 1A, an inner cylinder portion 1B and a hole portion 1C. FIG. 7 is a plan view showing the case after cutting of FIG. 5 and a B1-B2 sectional view thereof. In the figure, 2 is a case after cutting, and this case 2 is obtained by cutting the case 1 to integrally form a large diameter portion 3 and a joint 4 having a small diameter portion. And an end of the joint 4 are connected to each other, and an annular recess 2A (see FIG. 7B) is provided. A taper hole 4A and a mounting space 4B are formed in the center of the joint 4, and a screw hole 4C is formed in the side surface. The tapered hole 4A is a hole into which one end of a camshaft (not shown) of the fuel injection pump is fitted. The mounting space 4B is a space for fixing a bolt (not shown), and is screwed into a screw groove (not shown) cut at one end of the cam shaft (not shown) to The case 2 is fixed to one end of a cam shaft (not shown). The screw hole 4C is a screw hole for connecting and fixing a drive shaft (not shown).

FIG. 8 shows the inertia ring (with bearing) of FIG.
FIG. 5 is a plan view showing the above and a C1-C2 sectional view thereof. In the figure, reference numeral 5 denotes an inertia ring. The inertia ring 5 is provided with, for example, four thrust bearings 6 on its left side surface and right side surface, and has one journal bearing 7 on its inner peripheral surface. It is provided. FIG.
FIG. 6 is a plan view showing the lid of FIG. 5. In the figure, 8 is a lid, and this lid 8 is for sealing the annular recess 2A of the case 2. In FIG. 5, 9 is a viscous fluid such as silicone oil, and the viscous fluid 9 has a thrust bearing 6 and a journal bearing 7 assembled in a closed space formed by the annular recess 2A of the case 2 and the lid 8. The inertia ring 5 is housed in a relatively rotatable state.

Next, a method of manufacturing the viscous damper case having the above structure will be described. First, in FIG. 6, a case is integrally formed by forging the outer cylinder portion 1A, the inner cylinder portion 1B, and the hole portion 1C. And this outer cylinder part 1A
The inner peripheral side is cut to form a large-diameter portion 3 (see FIG. 7), and the outer peripheral side of the inner cylindrical portion 1B is cut to form an annular recess 2A (see FIG. 7). Then, the central portion of the hole portion 1C is cut to form the tapered hole 4A and the mounting space 4B (both refer to FIG. 7). Then, a screw hole 4C (see FIG. 7) is provided.

[0006]

However, in the conventional method for manufacturing a case for a viscous damper, the manufacturing cost is high since the cutting is performed after the integrated construction by forging.
There is a problem that the product becomes expensive. On the other hand, the inventor of the present invention has a drive shaft (not shown), which is a drive source, and a screw hole 4C.
(Case 2 for viscous damper) * Tapered hole 4A * As a result of analyzing the transmission of the driving force by the route of the camshaft (not shown) of the fuel injection pump, all of this driving force is screw hole 4C * for the viscous damper It is newly transmitted that it is transmitted by the route that passes through the joint 4 * taper hole 4A of the case 2, and is hardly transmitted by the route that passes through the screw hole 4C * viscous damper case 2 large diameter part 3 * lid 8 * joint 4 * taper hole 4A. I found it.

[0007]

A method for manufacturing a case for a viscous damper according to the present invention is a joint having a small diameter portion obtained by cutting a steel pipe into a predetermined length to create a large diameter portion and cutting forging. And one end surface of the large diameter portion is welded to one end surface of the joint having the small diameter portion to form an inertia ring, a plurality of bearings and an annular recess for enclosing the viscous fluid.

[0008]

According to the present invention, the manufacturing cost such as the material cost and the processing cost can be reduced, and the product can be inexpensive.

[0009]

FIG. 1 is a sectional view of a viscous damper case for explaining an embodiment of a method for manufacturing a viscous damper case according to the present invention. FIG. 2 is a plan view and a D1-D2 sectional view showing the large-diameter portion of FIG. In the figure, 1
Reference numeral 0 denotes a large-diameter portion, and the large-diameter portion 10 is made by cutting an electric resistance welded steel pipe into a predetermined length.
A is cut inside, and the other end surface 10B is cut so that a step is formed inside. Note that this step is a positioning for fitting and fixing the lid 8. FIG. 3 is a plan view showing a joint before cutting, which has a small-diameter portion formed by forging, and an E1-E2 sectional view thereof. In the figure, 11 is a joint before cutting, and this joint 11 has a tapered hole 11A,
It is composed of a mounting space 11B and a space portion 11C. FIG. 4 is a plan view showing a joint having a small diameter portion of FIG. 1 and a sectional view taken along line F1-F2 thereof. In the figure, 12
Is a joint after cutting, and the joint 12 is made by cutting the joint 11. And this joint 1
2 has a tapered hole 12A and a mounting space 12 at the center thereof.
B is formed, and a screw hole 12C is provided on the side surface.

Further, since the inertia ring 5 (see FIG. 5), the plurality of bearings 6 and 7 (see FIG. 5) and the viscous fluid 9 (see FIG. 5) are enclosed on the outer peripheral surface of the joint 12, there is a space. The part 12D is formed. The tapered hole 12A is, for example, one end of a camshaft (not shown) of a fuel injection pump inserted therein, and the mounting space 12B is a space for fixing a bolt (not shown). The joint 12 can be fixed to one end of the cam shaft (not shown) by screwing the bolt (not shown) into a thread groove (not shown) cut at one end of the cam shaft (not shown). it can. The screw hole 12C is a drive shaft (not shown) for rotationally driving the camshaft (not shown).
It is a screw hole for connecting and fixing.

Next, a method of manufacturing the viscous damper case having the above structure will be described. First, in FIG. 2, an electric resistance welded steel pipe is cut into a predetermined length, and then one end surface 10A thereof is cut.
The large diameter portion 10 can be formed by cutting and forming a step portion inside the other end surface 10B. Then, in FIG. 3, the joint 11 is integrally formed by forging.
Tapered hole 11A, mounting space 11B and space 11
A portion forming C is provided. Then, each part of the joint 11 is precisely cut to form a tapered hole 12A, a mounting cavity 12B, a screw hole 12C and a cavity 12D as shown in FIG. And in FIG. 1, the joint 12
It is possible to create a case by superimposing one end surface 10A of the large-diameter portion 10 on the end surface 12D1 of the hollow portion 12D and performing welding 13.

[0012]

As described above in detail, according to the method for manufacturing the viscous damper case according to the present invention, the manufacturing cost such as the material cost and the processing cost can be reduced, and the product can be inexpensive. There is an effect such as being able to.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a viscous damper case for explaining an embodiment of a method for manufacturing a viscous damper case according to the present invention.

FIG. 2 is a plan view showing the large diameter portion of FIG. 1 and its D1-D.
FIG.

3A and 3B are a plan view and a cross-sectional view taken along line E1-E2 of the joint before cutting, which has a small diameter portion formed by forging.

FIG. 4 is a plan view showing a joint having a small diameter portion of FIG. 1 and a sectional view taken along line F1-F2 thereof.

FIG. 5 is a cross-sectional view showing a conventional viscous damper.

6A and 6B are a plan view and a cross-sectional view taken along line A1-A2 of a case for a viscous damper before cutting, which is created by forging.

FIG. 7 is a plan view showing the case of FIG. 5 and its B1-B.
FIG.

FIG. 8 is a plan view showing the inertia ring (with a bearing) of FIG. 5 and a cross-sectional view taken along line C1-C2 thereof.

9 is a plan view showing the lid of FIG. 5. FIG.

[Explanation of symbols]

 10 Large diameter part 11 Joint before cutting 12 Joint 13 Welding

Claims (1)

[Claims] 1. A steel pipe is cut into a predetermined length to form a large diameter portion, forging is cut to form a joint having a small diameter portion, and one end surface of the large diameter portion is formed into a joint having a small diameter portion. A method for manufacturing a case for a viscous damper, characterized in that an inertia ring, a plurality of bearings and an annular recess for enclosing a viscous fluid are formed by welding to one end surface.