JPH0240884B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an elastic joint that connects one shaft and another shaft to transmit power and suppress the transmission of vibrations and the like. INDUSTRIAL APPLICATION This invention can be utilized for the elastic joint used for the connection of the propeller shaft which transmits the driving force of an engine, and the steering shaft which transmits the rotational force of a steering wheel, for example.

[Prior Art] An elastic joint, for example, an elastic joint used for connecting a propeller shaft, has a first mounting bracket 10 having an insertion hole 101a, as shown in FIGS. 5 and 6.
1, and a second mounting bracket 110 having an insertion hole 110a.
and an elastic member 106 consisting of a reinforcing cord part 104 and a rubber part 105 as main components,
This first mounting bracket 101 and second mounting bracket 11
0 are arranged alternately around the central axis 102 of one,
In this configuration, adjacent first mounting bracket 101 and second mounting bracket 110 are wrapped with reinforcing cord section 104 and covered with rubber section 105. In this elastic joint, as shown in FIG.
The second mounting fittings 110 are arranged in a regular polygon shape with the center axis 102 as the center. Therefore, the spring constant is almost the same during forward rotation and reverse rotation.

When using the elastic joint described above, as shown in FIG.
By connecting the mounting bracket 101 to the propeller shaft 107 and passing the other bolt 108 through the insertion hole 110a of the second mounting bracket 110, the second mounting bracket 1
10 is connected to the other shaft 109. By using the elastic joint described above, driving force can be transmitted while ensuring damping performance against vibrations and the like.

However, the propeller shaft of an automobile
7, the magnitude of the load and the frequency of use differ greatly between forward rotation and reverse rotation. Therefore, it is not desirable to use an elastic joint that has the same spring constant during forward rotation and reverse rotation.

Therefore, an elastic joint according to Japanese Utility Model Publication No. 56-35539 has been developed. In this elastic joint, the material of the elastic member that acts during forward rotation is different from the material of the elastic member that acts during reverse rotation.

[Problem that the invention seeks to solve]

The present invention was made in view of the above-mentioned fact that the magnitude of the load and the frequency of use differ between forward rotation and reverse rotation, and its purpose is to change the spring constant between the forward rotation direction and the reverse rotation direction. It is possible to provide elastic joints.

[Means for solving problems]

The elastic joint according to the present invention includes two or more first fittings connected to one shaft and arranged at equal intervals on a first circumference having one central axis; The two first circles are equally spaced and adjacent on the second circumference having the first central axis.
The number of second mounting brackets equal to the number of the first mounting brackets is arranged between the mounting brackets and in a position offset to one of the first mounting brackets, and the second mounting brackets are offset to one side. The first elastic members, which are elastically deformable in the same number as the first fittings, connect the first fittings and the second fittings, which are adjacent to each other and are close to each other, and the second fittings are offset. a second elastic member that is longer than the first elastic member and has the same number of elastically deformable elastic members as the first attachment fittings, which connects the second attachment fittings and the first attachment fittings that are adjacent to each other and are separated from each other due to the Consisting of
It is characterized by a configuration in which the spring constant in the forward direction and the spring constant in the reverse direction are different.

In the elastic joint according to the present invention, since the second fitting is offset, the length of the second elastic member is longer than the length of the first elastic member. The elastic joint of the present invention is, so to speak, an eccentric polygonal type. Here, the term "inclined polygonal shape" means that the imaginary line connecting the center axes of adjacent mounting brackets is not a regular polygon but an eccentric polygon. In the elastic joint according to the present invention, the elastic joint according to the present invention is configured such that tension is applied to the long second elastic member on the rotation side where the load is large and the frequency of use is high during normal rotation and reverse rotation. is interposed between one shaft and the other shaft.

Here, the first circumference and the second circumference are preferably the same circumference, but are not necessarily limited to this. If the first circumference and the second circumference are the same circumference, the first mounting bracket and the second mounting bracket are arranged not in a regular polygonal shape but in an eccentric polygonal shape.

Further, the first mounting bracket and the second mounting bracket may be formed of a simple cylinder, or may be formed of a central hole having a central axis substantially parallel to the first central axis, as exemplified in the embodiments described below. It is preferable to include a cylindrical outer member having a cylindrical outer member, an inner member held in a central hole of the outer member, and a lubricating member interposed between the inner member and the outer member. By providing the lubricating member in this way, the inner member and the outer member can move relative to each other in the axial direction. Therefore, when an external force is applied in the axial direction due to vibration or impact, the inner member can move relative to the outer member. sliding in the axial direction. Therefore, the axial spring constant of the elastic joint is
It can be lowered regardless of twist.

Furthermore, if an elastic seal layer is interposed between the inner member and the outer member together with a lubricating member, this elastic seal layer is compressively deformed in the radial direction of the outer member and the inner member, and as a result, the outer member and the inner member are separated. The period between 〓 is considered to be a non-clearance state with no gap. Therefore, there is an advantage that the inner member and the outer member can be reliably sealed.

[Effect]

In the elastic joint according to the present invention, the length of the first elastic member is different from the length of the second elastic member. Therefore, the spring constant in the normal rotation direction and the reverse rotation direction can be changed.

〔Effect of the invention〕

According to the elastic joint of the present invention, the spring constant in the forward direction and the spring constant in the reverse direction can be changed.

Therefore, the elastic joint connected to the propeller shaft of an automobile, in which the magnitude of the load differs greatly in the frequency of use during forward rotation (when the vehicle moves forward) and during reverse rotation (when the vehicle moves backward), has been tested. If the elastic joint according to the invention is applied, there will be an advantage that vibration can be effectively prevented. Further, according to the elastic joint of the present invention, since the spring constant in the forward rotation direction and the spring constant in the reverse rotation direction are changed by the second elastic member and the first elastic member, which are long in length, the spring constant can be adjusted using the mounting bracket. This is easier than doing it only inside.

〔Example〕

The elastic joint according to this embodiment is an example applied to an elastic joint connected to a propeller shaft of an automobile.

As shown in FIG.
A mounting bracket 2, the same number of first elastic members 3 as the first mounting bracket 1, and the same number of second elastic members 4 as the first mounting bracket.
It consists of.

The first mounting bracket 1 includes a first mounting bracket 1 having a central axis 5
They are arranged at equal intervals on the circumference 10.

The second mounting bracket 2 has a second mounting bracket 2 having a central axis 5.
They are arranged at equal intervals on the circumference 20. This second
As shown in FIG.
located between the first mounting brackets 1, and
It is arranged at a position offset to one of the first mounting brackets 1 side. Here, the first circumference 10 and the second circumference
The circumference 20 is the same circumference as shown in FIG. The first mounting bracket 1 and the second mounting bracket 2 are not arranged in a regular polygon shape centered on the central axis 5, but are arranged in an eccentric polygon shape.

The first elastic member 3 is a member that connects the first mounting bracket 1 and the second mounting bracket 2, which are in a state of approaching each other because the second mounting member 2 is offset, and connects the reinforcing cord portion 30 and the reinforcing cord. It consists of a disc-shaped elastic rubber part 6 that covers the part 30 from the outside.

The second elastic member 4 is a member that connects the second mounting bracket 2 and the first mounting bracket 1, which are in a distant state because the second mounting member 2 is offset, and connects the reinforcing cord portion 40 and the reinforcing cord. It consists of a disc-shaped elastic rubber part 6 that covers the part 40 from the outside. In addition, as shown in FIG. 1, the elastic rubber part 6 has reinforcing cord parts 30 and 40, a first fitting 1, and a second fitting 2 embedded therein. The elastic rubber part 6 has a chamfered outer side and has a central hole 60 and a hole 61 formed in a region surrounded by the reinforcing cord part 40. The holes 61 are provided primarily to save material and reduce weight.

In the elastic joint according to this embodiment, as shown in FIG. It is characterized by its location. Therefore, as shown in FIG.
The reinforcing cord portion 30 is set to be longer than the reinforcing cord portion 30 .

When using the elastic joint according to this embodiment, the first fitting 1 is connected to the drive shaft side, and the second fitting 2 is connected to the driven shaft side. Here, when the aforementioned drive shaft rotates normally in the direction of arrow B (FIG. 1), the first mounting bracket 1 also rotates in the same direction integrally with the drive shaft. When the drive shaft rotates in the normal direction, the second elastic member 4 is provided with a
A tensile stress is applied to the first elastic member 3 , and a compressive pressing force is applied to the first elastic member 3 , particularly the reinforcing cord portion 30 .

In this embodiment, as shown in FIG. 1, the length of the second elastic member 4, particularly the length of the reinforcing cord portion 40 of the second elastic member 4, is set longer than the length of the first elastic member 3. Because of this configuration, the spring constant in the driving direction, which is the normal rotation direction, can be made high, and the spring constant in the counter-driving direction, which is the reverse rotation direction, can be made low. Note that FIG. 2 shows a characteristic curve of displacement and torque of the elastic joint according to this embodiment.

Next, another example of the elastic joint according to the present invention will be described in the third example.
As shown in FIG. In this embodiment, the first fitting is attached to the outer member 70, as shown in FIG.
, an inner member 71, and a lubricating member 73 with rich lubricity.
and an elastic sealing layer 74 compressed in the radial direction. Here, the outer member 70 is fixed to the elastic rubber portion 6 by vulcanization adhesive, and has a cylindrical shape with a center axis 50 substantially parallel to the first center axis 5 . The outer member 70 has annular flange portions 70a extending radially outward at both ends in the axial direction. Also, the inner member 71 is the outer member 70
is held in the central hole of the Also, the inner member 71
has an outer circumferential diameter smaller than the inner circumferential diameter of the outer member 70, and has an annular flange portion 71 at both ends in the axial direction.
Has a. Here, the annular flange portion 71a and the annular flange portion 70a overlap with each other with a predetermined space. In this space, there is an elastic rubber seal section 75.
is mediated. The elastic rubber seal portion 75 is arranged substantially coaxially and continuously in a ring shape along the circumferential direction of the annular flange portion 70a of the outer member 70 and the annular flange portion 71a of the inner member 71. The lubricating member 73 is interposed between the inner surface forming the central hole of the outer member 70 and the outer peripheral surface of the inner member 71. This lubricating member 73 is formed of a resin layer whose main component is a fluororesin having a small coefficient of friction. The elastic seal layer 74 is the lubricant layer 7
3 and the outer member 70 in a compressed state. Since the elastic seal layer 74 is compressed in the direction of its flesh, a non-clearance state is created between the outer member 70 and the inner member 71.

Although not shown in the drawings in this embodiment, the second mounting bracket similarly has a structure including an outer member, an inner member, a lubricating member, and the like. Furthermore, similar to the embodiment shown in FIG. 1, the lengths of the first elastic member and the second elastic member are set to be different. Therefore, the spring constant in the forward direction and the spring constant in the reverse direction can be changed. Furthermore, when the elastic joint according to this embodiment is used while connected to a propeller shaft or the like, when vibration or impact force is applied in the axial direction of the elastic joint, the inner member 71 moves along the lubricating member 73 to the outer member 70. It slides in a direction almost parallel to its central axis. Therefore, there is an advantage that the axial spring constant of the elastic joint can be reduced almost independently of torsion.

Still another embodiment of the elastic joint according to the present invention is shown in FIG. In this embodiment, the first elastic member 8
A plurality of second elastic members 9 are provided,
are connected to each other. Here, the first elastic member 8
The reinforcing cord part 80 connects the first mounting bracket 1 and the second mounting bracket 2, which are in a state of being close together because the second mounting bracket 2 is offset, and the reinforcing cord part 8.
and an elastic rubber part 81 that covers 0. Also, the second
The elastic member 9 includes a reinforcing cord portion 90 that connects the first mounting bracket 1 and the second mounting bracket 2, which are in a distant state due to the second mounting bracket 2 being offset, and an elastic rubber that covers the reinforcing cord portion 90. It consists of a part 91.

[Brief explanation of drawings]

1 and 2 show one embodiment of the present invention, FIG. 1 is an enlarged plan view of an elastic joint, and FIG. 2 is a graph showing the relationship between torque and displacement. FIG. 3 shows another embodiment of the elastic joint according to the present invention, and is a longitudinal cross-sectional view of the vicinity of the first mounting bracket of the elastic joint, and FIG. 4 shows a further different embodiment according to the present invention. FIG. FIG. 5 is a plan view showing the right half of a conventional elastic joint in section, and FIG. 6 is a sectional view showing the state in which the elastic joint is used. In the figure, 1 is the first mounting bracket, 2 is the second mounting bracket,
3 is a first elastic member, 4 is a second elastic member, 5 is one central axis, 70 is an outer member, 71 is an inner member, 7
3 is a lubricating member, 74 is an elastic seal layer, 8 is a first elastic member, and 9 is a second elastic member.

Claims (1)

[Claims] 1. Two or more first rings connected to one shaft and arranged at equal intervals on a first circumference having one central axis
a mounting bracket, and two adjacent first shafts connected to the other shaft at equal intervals on a second circumference having the central axis of the first shaft.
The number of second mounting brackets equal to the number of the first mounting brackets is arranged between the mounting brackets and in a position offset to one of the first mounting brackets, and the second mounting brackets are offset to one side. A first elastic member, which is elastically deformable in the same number as the first fittings, connects the first fittings and the second fittings that are adjacent to each other and close to each other, and the second fittings are offset. elastically deformable second fittings, which are longer than the first elastic members and have the same number as the first fittings, and which connect the second fittings and the first fittings, which are adjacent to each other and spaced apart due to the An elastic joint comprising: an elastic member, characterized in that the spring constant in the forward direction and the spring constant in the reverse direction are different. 2. The elastic joint according to claim 1, wherein the first circumference and the second circumference are the same circumference. 3. The first elastic member and the second elastic member are formed of a reinforcing cord section that wraps around the first mounting bracket and the second mounting bracket, respectively, and an elastic rubber section that covers the reinforcing cord section. An elastic joint according to claim 1. 4. At least one of the first mounting bracket and the second mounting bracket includes a cylindrical outer member having a central hole having a central axis substantially parallel to the central axis of the first mounting bracket, and a cylindrical outer member held within the central hole of the outer member. It is composed of an inner member and a lubricating member interposed between the outer member and the inner member, and the inner member is slidable relative to the outer member in a direction substantially parallel to the central axis. An elastic joint according to claim 1.