JPH09273600A - Torsional damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lighten and improve the damping property of a torsional damper having in its hub a jig-engaging service hole for preventing the corotation thereof in fixation or removal to or from a rotating shaft end. SOLUTION: An engaging plate 40 is fixed on the inner circumference of an outer cylindrical section 12 of a hub 10 made of a metal plate. The engaging plate 40 comprises a fitting cylindrical section 41 press-fitted on the inner circumference of the outer cylindrical section 12 and a flange 42 extended from the end of the fitting cylindrical section 41 at the face side toward the bore. The flange 42 is spaced away from a boss member 14 of the hub 10 to the face side by an appropriate distance, and has at its bore a hexagonal jig-engaging service hole 40a punched out for engaging the hexagonal outer circumference of a hollow hexagonal engaging jig.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torsional damper that absorbs torsional vibration generated on a rotating shaft such as a crankshaft of an engine.

[0002]

2. Description of the Related Art In order to effectively absorb the torsional vibration (rotational vibration) generated by the rotation of the crankshaft of an automobile engine, the axial end of the crankshaft protruding from the crank chamber of the engine has a torsional vibration. The damper is installed. As a typical conventional example of this type of torsional damper, there is one as shown in FIG. 5, for example, reference numeral 101 indicates an engine through a center bolt 2 inserted through the inner circumference of a boss portion 101a having an inner diameter. A hub attached to the axial end of the crankshaft 1, a sleeve 102 fitted to the outer peripheral surface of the outer diameter cylindrical portion 101b of the hub 101, an annular mass body 103 concentrically arranged on the outer peripheral side of the hub 101, Is an annular elastomer vulcanized and bonded between the cylindrical surfaces of the sleeve 102 and the mass body 103 facing each other. The torsional damper 100 includes a mass body 1
The resonance system composed of 03 and the elastomer 104 resonates at a phase angle different from the torsional vibration of the crankshaft 1 in a predetermined frequency range, thereby exhibiting the damping property against the torsional vibration.

In the conventional example shown in the figure, a pulley portion 102a is formed on the outer peripheral surface of the mass body 102, and the pulley portion 10 is also formed on the front portion of the hub 101 (on the side opposite to the engine).
1c is integrally provided. In addition, on the front side of the boss 101a of the hub 101, the boss 101a
Is formed with a service hole 101d whose diameter is larger than that of the inner peripheral hole and whose front shape is a regular hexagon. This jig engaging service hole 101d is used for removing the torsional damper 100 from the shaft end of the crankshaft 1 or for conversely attaching it to the shaft end of the crankshaft 1 at the time of inspection or maintenance of the engine. When the center bolt 2 is turned in the loosening direction or the fastening direction, as shown in FIG. 6, by inserting and engaging a hollow engaging jig 3 having an outer periphery of a hexagonal column, both the crankshaft 1 and the torsional damper 100 are engaged. The hexagon socket with socket 4 for rotating the center bolt 2 is provided for preventing the turning, and is passed through the hollow portion 3a of the engaging jig 3 to
The hexagonal hole 4a at the tip of the socket 4 is fitted into the head portion 2a of the center bolt 2.

[0004]

According to the torsional damper according to the above-mentioned conventional example, the jig engaging service hole 101d is formed in the hub 101 by forming the hub 101 by casting. For this reason, the manufacturing cost becomes high and the weight of the hub 101 increases,
There is a problem that the dynamic vibration absorbing function of the resonance system including the mass body 103 and the elastomer 104 is deteriorated. Hub 1
When 01 is made of cast metal, it is pointed out that the axial position of the jig engaging service hole 101d cannot be arbitrarily changed. That is, for example, in the case where a pulley portion 101c is provided on the front side of the hub 101 as in the illustrated conventional example, insertion and engagement of the engagement jig 3 can be easily performed when attaching or detaching the torsional damper. In order to achieve this, it is effective to form the jig engaging service hole 101d closer to the front (left side in the figure) than the position shown in the drawing, but in this case, the hub 101 must be thickened, Therefore, the weight increases and the dynamic vibration absorbing function deteriorates.

The present invention has been made under the circumstances as described above, and its technical problem is that the hub is
It is intended to reduce the weight of a torsional damper having a service hole for preventing co-rotation when attaching or detaching the rotary shaft to the shaft end, and to improve the vibration damping property.

[0006]

The above-mentioned technical problems are as follows.
This can be effectively solved by the present invention. That is, the torsional damper according to the present invention includes a hub formed by molding a metal plate into an annular shape, an annular mass body that is concentrically arranged near the hub, and an elastomer that elastically connects the hub and the mass body. And a engaging plate having a polygonal jig engaging service hole, which is integrally fixed to the hub and has a diameter larger than the head of the center bolt for fixing the inner diameter end of the hub to the end of the rotating shaft on the inner circumference. It consists of and. Therefore, the axial position of the jig engaging service hole can be arbitrarily changed depending on the fixing position of the engaging plate with respect to the hub or the cross-sectional shape of the engaging plate, in which case the hub wall thickness is not changed. The dynamic vibration absorbing function does not decrease due to the increase in the weight.

[0007]

1 is a half sectional view of a first embodiment of a torsional damper according to the present invention. In addition,
The "front side" used in the following text refers to the direction in which the axial end of the crankshaft 1 to which the torsional damper is attached faces (left side in the figure), and the opposite side to the "engine side" (right side in the figure). ).

In the torsional damper of this embodiment, the hub 10 is made of an annular metal plate and has a flange portion 11 and an outer peripheral cylindrical portion extending from the outer peripheral end portion to the front side. 12 and a pulley portion 13 formed on the front side of the outer peripheral cylindrical portion 12, and the boss member 14 is provided at the inner diameter end of the flange portion 11 formed in a tapered shape whose inner diameter side projects toward the engine side. Are fixed by welding or the like. The mass body 20 is also made of a metal plate formed in an annular shape having a substantially U-shaped cross section, and a pulley portion 21 is integrally formed on the outer periphery thereof, and is concentrically located near the outer peripheral side of the cylindrical portion 12 of the hub 10. It is arranged. The elastomer 30 that elastically connects the hub 10 and the mass body 20 is vulcanized and bonded between the outer peripheral cylindrical portion 12 of the hub 10 and the inner peripheral cylindrical portion 22 of the mass body 20 that are radially opposed to each other. There is.

On the inner peripheral surface of the outer peripheral cylindrical portion 12 of the hub 10,
The engagement plate 40 is fixed. The engagement plate 40 includes a fitting cylinder part 41 press-fitted to the inner peripheral surface of the outer peripheral cylinder part 12, and a flange part extending from the front end of the fitting cylinder part 41 toward the inner diameter side. 42 and. The flange portion 42 is located at an appropriate distance from the boss member 14 of the hub 10 toward the front side, and the inside diameter thereof is the hexagonal column-shaped hollow engaging jig 3 as described above with reference to FIG. A hexagonal jig engaging service hole 40a capable of engaging with the outer peripheral surface of the hexagonal column is punched out. The torsion damper is a boss member 14 having an inner diameter of the hub 10.
The hexagon socket 4 for tightening (or loosening) the center bolt 2 is to be attached to the shaft end of the crankshaft 1 of the engine via the center bolt 2 inserted through the socket, as shown in FIG. Hanging jig 3
The jig engaging service hole 40a has a larger diameter than the head portion 2a of the center bolt 2 because the jig engaging service hole 40a is inserted from the hollow portion 3a.

When inspecting or maintaining the engine,
The torsional damper having the above-described structure is used for the crankshaft 1
In order to release the fixing of the boss member 14 of the hub 10 by the center bolt 2 when removing from the shaft end, the engaging jig 3 (see FIG. 6) is inserted into the jig engaging service hole 40a of the engaging plate 40 from the front side. By inserting and engaging, the crankshaft 1 is prevented from rotating through the engaging plate 40 and the hub 10, and the hexagon socket at the tip of the socket 4 with hexagonal hole (see FIG. 6) inserted from the inner periphery of the engaging jig 3 is inserted. Four
A is fitted to the head portion 2a of the center bolt 2 and rotated in the loosening direction. The same applies when the removed torsional damper is fastened and fixed again to the shaft end of the crankshaft 1 with the center bolt 2. In this case, since the jig engaging service hole 40a by the flange portion 42 of the engaging plate 40 is provided at a position sufficiently distant from the boss member 14 of the hub 10 to the front side, the pulley portion on the front side of the hub 10 is provided. It is possible to eliminate the difficulty of inserting / engaging the engaging jig 3 due to the presence of 13.

Further, according to the above construction, the engaging plate 4
0 has a function of relieving the tensile stress of the elastomer 30. That is, the outer peripheral cylindrical portion 12 of the hub 10 and the mass body 2
Elastomer 3 vulcanization molded between the inner peripheral cylindrical portion 22 of
At 0, a tensile stress is generated due to volume contraction after molding, and thereafter, the fitting cylinder portion 41 of the engaging plate 40 is press-fitted onto the inner circumference surface of the outer circumference cylindrical portion 12 of the hub 10 to make the outer circumference. Since the cylindrical portion 12 is slightly expanded in diameter so as to compress the elastomer 30 to the outer diameter side, the tensile stress is eliminated.

In the embodiment shown in FIG. 1, the jig engaging service hole 40a is formed by punching the engaging plate 40. However, as shown in FIGS. 2A and 2B, for example, as shown in FIGS. It may be formed by bending the inner diameter portion 42a of the flange portion 42 of the plate 40 toward the engine side or the front side in a hexagonal tubular shape. By doing so, the jig engaging service hole 40a
Further, it is possible to stabilize the engaging jig 3 to be engaged therewith, to arbitrarily set the axial position (length) of the jig engaging service hole 40a, and to improve the strength of the engaging plate 40. Further, the axial position of the jig engaging service hole 40a can be arbitrarily set by the axial fitting position of the fitting tubular portion 41 of the engaging plate 40 to the outer peripheral cylindrical portion 12 of the hub 10.

FIG. 3 is a half-cut sectional view showing a second embodiment of the torsional damper of the present invention. In the torsional damper of this embodiment, the hub 1 made of a metal plate is used.
No. 0 has a taper shape in which the inner peripheral portion of the flange portion 11 projects toward the engine side, and the boss member 14 is fixed to the inner diameter end portion thereof by welding or the like, and is formed in the radial middle portion of the flange portion 11. An annular stepped portion 11a having a shape in which the outer diameter side projects to the front side is formed, and has an outer peripheral cylindrical portion 15 extending from the outer diameter end of the flange portion 11 to the engine side. The mass body 20 is made of a casting or the like, is concentrically arranged on the outer peripheral side of the outer peripheral cylindrical portion 15 of the hub 10, and has a pulley portion 23 formed on the outer peripheral surface thereof. The outer peripheral cylindrical portion 15 of the hub 10 and the inner peripheral surface 24 of the mass body 20, which are opposed to each other in the radial direction, have cross-sectional shapes cut along a plane passing through the axial center in a corrugated shape corresponding to each other.
The elastomer 30 that elastically connects the hub 10 and the mass body 20 includes an outer peripheral cylindrical portion 15 and an inner peripheral surface 22 of the mass body 20.
It is press-fitted between and.

The hub 10 is not formed with a pulley portion as in the embodiment of FIG. 1, but a pulley portion 43 corresponding to this is formed.
Are formed on the engaging plate 40. That is, the engagement plate 40 includes a fitting tubular portion 41 fitted to the inner peripheral surface of the annular step portion 11a of the flange portion 11 of the hub 10, and a pulley portion 43 formed on the front side of the fitting tubular portion 41. When,
The fitting tubular portion 41 has a pulley portion 43 and a flange portion 42 extending from the end portion on the opposite side to the inner diameter side. The flange portion 42 of the engaging plate 40 is the flange portion 1 of the hub 10.
1 are fixed by welding W or screwing at a plurality of positions in the circumferential direction. The flange portion 42 is located at an appropriate distance from the boss member 14 of the hub 10 toward the front side, and the jig engaging service hole 40a is provided in the flange portion 4
It is formed by bending the second inner diameter portion 42a into a hexagonal tubular shape toward the front side.

In the second embodiment, as shown in FIGS. 4A and 4B, the jig engaging service hole 40a has an inner diameter portion 4 of the flange portion 42 of the engaging plate 40.
It may be formed by punching out 2a or by bending it in a hexagonal cylindrical shape toward the front side.

The present invention should not be limitedly interpreted by the illustrated embodiments. For example, the jig engaging service hole 40a may have a polygonal shape other than a hexagon depending on the outer surface shape of the engaging jig 3.

[0017]

According to the present invention, the following effects are realized. (1) Since the service hole for jig engagement is formed in the engagement plate integrated with the hub and the hub is formed of a metal plate, the manufacturing cost can be reduced. (2) Since the hub can be formed of a metal plate to reduce the weight, the dynamic vibration absorbing function of the resonance system including the mass body and the elastomer does not deteriorate. (3) The axial position of the jig engaging service hole can be arbitrarily changed according to the shape of the hub without changing the thickness of the hub.

[Brief description of drawings]

1A and 1B show a first embodiment of a torsional damper of the present invention, where FIG. 1A is a half-cut sectional view taken along a plane passing through an axis, and FIG. 1B is a partial front view.

FIG. 2 is a partial cross-sectional view showing an example of the shape of the engaging plate in the above embodiment.

FIG. 3 is a half cross-sectional view showing a second embodiment of a torsional damper of the present invention by cutting along a plane passing through an axis.

FIG. 4 is a partial cross-sectional view showing an example of the shape of the engaging plate in the above embodiment.

FIG. 5 is a half sectional view showing a conventional torsional damper cut along a plane passing through an axis.

FIG. 6 is a partial perspective view showing an operation of attaching or detaching the torsional damper to or from the shaft end of the crankshaft.

[Explanation of symbols]

 1 Crank Shaft (Rotation Shaft) 2 Center Bolt 2a Head 3 Engaging Jig 3a Hollow Part 4 Socket with Hexagonal Hole 4a Hexagonal Hole 10 Hub 11,42 Flange Part 11a Annular Step 12,15 Outer Cylindrical Part 13,21,23 , 43 Pulley portion 14 Boss member 20 Mass body 22 Inner peripheral surface 30 Elastomer 40 Engaging plate 40a Jig engaging service hole 41 Fitting cylinder

Claims (1)

[Claims] 1. A hub (10) formed by molding a metal plate into an annular shape.
An annular mass body (20) concentrically arranged near the hub (10); an elastomer (30) elastically connecting the hub (10) and the mass body (20); For hooking a polygonal jig having a diameter larger than the head (2a) of the center bolt (2) integrally fixed to (10) and fixing the inner diameter end of the hub (10) to the rotary shaft end on the inner circumference. Engagement plate (4) with service hole (40a)
0) and a torsional damper.