JP2003176853A - Transmission chain - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission chain capable of preventing cutting of chain by not receiving the bearing pressure between a guide member and an upper or lower end face of the transmission chain only by an outer plate so as to suppress the wear at the both side end parts of the guide member, and by preventing the reduction in fitting force between the pin hole of the outer plate and a connection pin when the transmission chain consisting of a roller chain or a bush chain travels in sliding contact with the guide member. <P>SOLUTION: In a state where the outer plate 21 and an inner plate 23 constituting the roller chain 21 are disposed in a manner that brings a pitch line 27 connecting centers of each pin hole 22a and bush hole 23a into a horizontal line, the upper end face 22b of the outer plate 22 is disposed below the upper end face 23b of the inner plate 23 by 1/2 of the difference between the inner diameter of the bush 24 and the outer diameter of the connection pin 26 to form the roller chain, so that the upper end face 22b and 23b are positioned on the same plane in sliding contact with the guide member. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission chain composed of a roller chain or a bush chain used for transmitting power in an automobile, an industrial machine or the like, and more particularly, when traveling by sliding on a guide member. A transmission chain suitable for use.

[0002]

2. Description of the Related Art Transmission chains consisting of roller chains or bush chains are used for power transmission parts of automobile engines, general-purpose engines, industrial machines, etc. 4 and 5 show how the transmission chain used in the timing transmission mechanism for transmitting to the camshaft is used. Less than,
A conventional roller chain that is an example of this transmission chain will be described with reference to FIGS. 6 and 7.

As shown in FIG. 4, the timing transmission mechanism 1 includes a crankshaft sprocket 2, a camshaft sprocket 3, a roller chain 4 wound around these sprockets 2 and 3, a guide 5, and a tensioner 6. , And the tensioner lever 7. Here, the guide 5 or the tensioner lever 7, which is a guide member, is provided outside the orbiting roller chain 4, but as a timing transmission mechanism, the guide member or the tensioner lever 7 of the orbiting roller chain 4 is used. It may be provided inside.

The guide 5 is a guide member that prevents the roller chain 4 from being overtightened or loosened during assembly and running, and also prevents vibration and lateral shake of the roller chain 4 during running. Also, the tensioner lever 7
It is a guide member that is pressed by the tensioner 6 and is brought into sliding contact with the roller chain 4 to give an appropriate tension, and at the same time, prevents the traveling roller chain 4 from vibrating and swaying.

The roller chain 4 is shown in FIGS. 6 (A) and 6 (B).
As shown in FIG. 2, a substantially oval outer plate 8 having a pair of pin holes 8a, a substantially oval inner plate 9 having a pair of bush holes 9a, and a bush hole of the inner plate 9 are formed. Bush 10 fitted and fixed to 9a and this bush 1
Roller 11 loosely fitted to the outer peripheral side of 0 and this bush 10
And the pin hole 8a of the outer plate 8
And a connecting pin 12 fitted and fixed to.

In this roller chain 4, a pair of outer plates 8, 8 and a pair of inner plates 9, 9 connected by a bush 10 in which a roller 11 is loosely fitted are displaced from each other in the longitudinal direction to form a connecting pin. Bush 1 formed by connecting 12
The connecting pin 12 rotates using 0 as a bearing.

The conventional roller chain 4 is shown in FIG.
As shown in (B), in a state in which the outer plate 8 and the inner plate 9 are arranged so that the pitch line 13 connecting the pin holes 8a and the bush holes 9a at the center becomes a horizontal straight line,
The upper end surface 8b of the outer plate 8 and the upper end surface 9b of the inner plate 9
And the lower end surfaces 8c and 9c of the both are formed to be flush with each other, and in the state arranged as described above, the upper end surfaces 8b, 9b, and the lower end surface 8c of the entire roller chain 4 are 9c is formed so as to be flush.

That is, if the distance between the upper end surface 8b of the outer plate 8 and the pitch line 13 is K1, and the distance between the upper end surface 9b of the inner plate 9 and the pitch line 13 is K2, then K1
= K2, and the lower end surface 8c of the outer plate 8
When the distance between the pitch line 13 and the pitch line 13 is K3, and the distance between the lower end surface 9c of the inner plate 9 and the pitch line 13 is K4,
The relationship is K3 = K4. In this case, each plate has a relationship of K1 = K2 = K3 = K4 or K1 = K
The relationship is 2 ≠ K3 = K4.

Further, since the connecting pin 12 is loosely fitted into the inside (in the cylinder) of the bush 10 fitted and fixed in the bush hole 9a of the inner plate 9, the inner diameter M1 of the bush 10 and the outer diameter of the connecting pin 12 are increased. A difference (gap) M = M1-M2 occurs between M2 and M2.

[0010]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
When the upper end surface of the outer plate 8 is pressed by the tensioner lever 7 which is a guide member to travel, the connecting pin 12 is fitted and fixed in the pin hole 8a of the outer plate 8, while it is fitted and fixed in the bush hole 9a of the inner plate 9. Since the connecting pin 12 is loosely fitted in the inside of the bush 10 with a difference (gap) M, the inner plate 9 freely moves up and down, and as shown in FIG.
As shown in (B), the upper end surface 9b of the inner plate 9 is lower than the upper end surface 8b of the outer plate 8 in the figure, and the step K
Occurs. This step K is at most half the difference (gap) M between the inner diameter of the bush hole 9a and the outer diameter of the connecting pin 12,
That is, the step K = (1/2) · M.

Therefore, as shown in FIG. 7C, when the tensioner lever 7 pressed by the tensioner 6 is brought into pressure contact with the roller chain 4, the upper end surface 8b of the outer plate 8 will be described.
Only the (dotted portion) contacts the tensioner lever 7, and the surface pressure between the tensioner lever 7 and the roller chain 4 is received only by the outer plate 8.

As a result, the shoe 7 of the tensioner lever 7
a Abrasion of both side end portions is promoted, friction loss is increased, and a load is applied only to the fitting fixing portion between the pin hole 8a of the outer plate 8 and the connecting pin 12, so that the fitting force is weakened and the connecting pin 12 is There is a problem that it may come off and the roller chain may be cut.

As described above, the upper end surface 9b of the inner plate 9 is
If there is a step K between the outer plate 8 and the upper surface 8b of the outer plate 8, the shoe 7a of the tensioner lever 7 and the inner plate 9
There is a gap corresponding to the step K between the upper end surface 9b of the inner plate 9 and the upper end surface 9b of the inner plate 9, and the upper end surface 9b of the inner plate 9 is not pressed by the tensioner lever 7 as shown by K ′ (gap portion K ′) in FIG. Due to the step K, the outer plate 8 comes into contact with the tensioner lever 7 only every one pitch, so that the roller chain 4 cannot smoothly enter below the tensioner lever 7 and the traveling behavior becomes unstable. .

Above, the upper end surfaces 8b, 9 of the roller chain 4
The problem at the time of sliding contact travel between b and the tensioner lever 7 which is a guide member provided on the outer side of the orbiting roller chain 4 has been described, but the guide member is provided on the inner side of the orbiting roller chain 4. In this case, when the lower end surfaces 8c and 9c of the roller chain 4 are slidably in contact with the guide member to travel, the same problem still occurs. Further, each of the above problems is also a problem common to bush chains that are not provided with rollers.

Therefore, the present invention solves the problems of the prior art as described above, and when the transmission chain consisting of the roller chain or the bush chain slides on the guide member and travels, the guide member and the transmission chain are The surface pressure of the outer plate is not received only by the upper end surface or the lower end surface of the outer plate to prevent abrasion of both side ends of the guide member and prevent the fitting force between the pin hole of the outer plate and the connecting pin from decreasing. To prevent the chain from cutting, and eliminate the step between the upper and lower end surfaces of the outer plate and inner plate or between the lower end surfaces to allow the transmission chain to enter the guide member smoothly. The purpose is to provide a transmission chain that can be performed.

[0016]

In order to achieve the above object, the present invention provides a bush fitted and fixed in a pair of bush holes formed in an inner plate and loosely fitted in the bush. In a transmission chain mainly composed of a connecting pin fitted and fixed to a pair of pin holes formed in the outer plate, a transmission chain consisting of a roller chain or a bush chain, the outer plate and the inner plate both have parallel upper end surfaces. Formed of a substantially oval plate having a lower end surface,
With the outer plate and the inner plate arranged so that the pitch lines connecting the centers of the pin holes and bush holes of these plates are arranged in a horizontal straight line, the upper end surface of the outer plate is The transmission chain is located below the difference between the inner diameter and the outer diameter of the connecting pin by 1/2.

According to another aspect of the present invention, in the transmission chain, the outer plate and the inner plate are arranged such that a pitch line connecting the centers of the pin hole and the bush hole becomes a horizontal straight line. In this state, the lower end surface of the outer plate is located above the lower end surface of the inner plate by ½ of the difference between the inner diameter of the bush and the outer diameter of the connecting pin,
This is the structure.

[0018]

In the transmission chain of the present invention, when the outer plate and the inner plate are arranged so that the pitch line connecting the centers of the pin hole and the bush hole of these plates becomes a horizontal straight line, The end surface has a difference of 1 between the inner diameter of the bush and the outer diameter of the connecting pin from the upper end surface of the inner plate.
Since the upper end surface of the transmission chain slides on the guide member and travels, the inner plate moves downward so that the upper end surface of the outer plate and the upper end surface of the inner plate are located below each other by 1/2. They are flush with each other, and there is no step, and the entire upper end face of the transmission chain is flush.

The lower end surface of the outer plate is less than the lower end surface of the inner plate by a difference of 1 between the inner diameter of the bush and the outer diameter of the connecting pin.
Since the lower end surface of the transmission chain slides on the guide member and travels, the inner plate moves upward, and the lower end surface of the outer plate and the lower end surface of the inner plate are positioned by 1/2. The steps are flush with each other, and the step is eliminated, and the entire lower end surface of the transmission chain is flush.

As described above, when the upper end surface or the lower end surface of the entire transmission chain is substantially flush, the guide members are evenly contacted, so that the upper end surface or the lower end surface of the outer plate and the guide member are separated from each other. Since the surface pressure of is reduced, the fitting force between the pin hole of the outer plate and the connecting pin does not decrease, and the transmission chain is prevented from being cut.

Further, when the upper end surface or the lower end surface of the entire transmission chain becomes flush with each other and the step is eliminated, the transmission chain can smoothly enter below or above the guide member.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to FIGS. The transmission chain of the first embodiment is
It is composed of a roller chain, and FIG. 1 (A) shows a partial side view of the roller chain 21, FIG. 1 (B) shows its sectional view, and FIG. 2 (A), (B), ( C) shows the state at the time of contact with the guide member.

The roller chain 21 is shown in FIG.
As shown in (B), an outer plate 22 having a pair of pin holes 22a, an inner plate 23 having a pair of bush holes 23a, and a bush hole 23 of the inner plate 23.
The bush 24 fitted and fixed to a, the roller 25 loosely fitted to the outer peripheral portion of the bush 24, the bush 24 loosely fitted to the inside of the bush 24, and fitted and fixed to the pin hole 22a of the outer plate 22. And a connecting pin 26.

In this roller chain 21, a large number of a pair of outer plates 22, 22 and a pair of inner plates 23, 23 connected by a bush 24 in which a roller 25 is loosely fitted are mutually displaced in the longitudinal direction. It is formed by connecting with the connecting pin 26, and the connecting pin 26 rotates using the bush 24 as a bearing.

Further, the outer plate 2 of the roller chain 21
2 and the inner plate 23 are parallel to each other at the upper end surface 22.
It is formed of a substantially oval plate having b and 23b and lower end faces 22c and 23c.

The outer diameter of the roller 25 is smaller than the distance between the upper end surface 22b and the lower end surface 22c of the outer plate 22. For this reason, when the roller chain 21 travels in sliding contact with a guide member (not shown), only the upper end surface or the lower end surface thereof slides in contact with the guide member, and the roller 25 does not contact.

First, regarding the positional relationship between the upper end surfaces 22b and 23b, as shown in FIG. 1 (A), the outer plate 2
2 and the inner plate 23, the pin hole 22a and the bush hole 2
In a state where the pitch line 27 connecting the centers of 3a is arranged so as to be a horizontal straight line, the upper end surface 22b of the outer plate 22 is larger than the inner end Q1 of the bush 24 and the connecting pin 26 from the upper end surface 23b of the inner plate 23. Difference Q from outer diameter Q2
It is located ½ of (Q = Q1-Q2) below.

That is, the bush hole 23 of the inner plate 23
The connecting pin 26 is loosely fitted inside the bush 24 fitted and fixed to a, and there is a clearance.
And the outer diameter Q2 of the connecting pin 26, there is a difference of Q1-Q2 = Q.

The distance between the upper end surfaces 22b of the outer plate 22 and the pitch line 27 is P1, and the inner plate 2 is
When the distance between the upper end surfaces 23b of the upper end surface 23b and the pitch line 27 is P2, the upper end surface 22b of the outer plate 22 has a step P = P2-P1 and the upper end surface 23b of the inner plate 23 is
In a lower position. That is, the distance P1 between the upper end surfaces of the outer plate 22 is equal to the distance P2 between the upper end surfaces of the inner plate 23.
Smaller than

In the above, the upper end surface 2 of the outer plate 22
2b from the upper end surface 23b of the inner plate 23, the bush 24
Between the inner diameter Q1 and the outer diameter Q2 of the connecting pin 26 (Q = Q
1-Q2) is located half way down,
This means that there is a step P = (1/2) · Q between the upper end surface 22b of the outer plate 22 and the upper end surface 23b of the inner plate 23.

The roller chain 21 formed in this way
The upper end surfaces 22b and 23b are guide members (not shown).
2A and 2B, the inner plate 23 moves downward by a step P due to the sliding contact, and the upper end surface 22b of the outer plate 22 and the inner plate 23 move. The upper end surface 23b is flush with the roller chain 2
The entire upper end surfaces 22b and 23b of 1 are substantially flush with each other.

Therefore, when the roller chain 21 travels in sliding contact with a guide member (not shown), the upper end surface 22b of the outer plate 22 and the upper end surface 23b of the inner plate 23 are moved as shown in FIG. 2C. The guide members are evenly contacted, and the surface pressure between the guide member and the roller chain 21 is received by the upper end surfaces 22b and 23b of both plates. Note that, in FIG. 2C, a portion that comes into contact with the guide member is shown by a halftone dot.

As a result, the upper end surface 2 of the roller chain 21 is
When 2b and 23b run in sliding contact with the guide member, it is possible to prevent abrasion of both end portions of the guide member and increase of friction loss, and to prevent the pin hole 22a of the outer plate 22 from being damaged. It is possible to suppress the load applied to the fitting and fixing portion with the connecting pin 26, and accordingly to prevent the connecting pin 26 from coming off due to the weakening of the fitting force, and to prevent the roller chain 21 from being cut.

Next, regarding the positional relationship between the lower end surface 22c and the lower end surface 23c, similar to the positional relationship between the upper end surfaces,
As shown in FIG. 1A, the outer plate 22 and the inner plate 23 are arranged in such a manner that the pitch line 27 connecting the centers of the pin holes 22a and the bush holes 23a becomes a horizontal straight line. The lower end surface 22c of the bush 24 is smaller than the inner surface Q of the bush 24 from the lower end surface 23c of the inner plate 23.
1 and the outer diameter Q2 of the connecting pin 26, Q (Q = Q1-Q
It is located half above 2). That is, the lower end surface 22b of the outer plate 22 and the lower end surface 23b of the inner plate 23.
There is a step P = (1/2) · Q between

Here, the lower end surface 22c of the outer plate 22 is
The distance between the lower end surfaces of the pitch line 27 and the pitch line 27 is P1, the distance between the lower end surface 23c of the inner plate 23 and the pitch line 27 is P2, and the step P = P2-P1 = (1 /
2) ・ There is a relationship of Q. Then, the outer plate 22 and the inner plate 23 are formed in advance so as to have such a positional relationship.

The roller chain 21 has a lower end surface 2
2c and the lower end surface 23c run in sliding contact with a guide member (not shown), the sliding contact causes only the step P to move the inner plate 2
3 moves upward, the lower end surface 22c of the outer plate 22 and the lower end surface 23c of the inner plate 23 are flush, and the lower end surfaces 22c and 23c of the roller chain 21 are generally flush (not shown).

As described above, since the entire lower end surface of the roller chain 21 is substantially flush with the roller chain 21,
When the vehicle slides on the guide member and travels, the outer plate 22
Lower end surface 22c of the inner plate 23 and the lower end surface 23c of the inner plate 23 evenly contact the guide member, and the surface pressure between the guide member and the roller chain 21 is reduced to the lower end surfaces 22c and 23c of both plates.
Will be accepted by.

As a result, the lower end surface 2 of the roller chain 21 is
When 2c and 23c travel in sliding contact with the guide member, it is possible to prevent abrasion of both end portions of the guide member and increase of friction loss, and to prevent the pin hole 22a of the outer plate 22 from being damaged. It is possible to suppress the load applied to the fitting and fixing portion with the connecting pin 26, and accordingly to prevent the connecting pin 26 from coming off due to the weakening of the fitting force, and to prevent the roller chain 21 from being cut.

The second embodiment will be described with reference to FIG. The transmission chain of the second embodiment is formed of a bush chain, and FIG. 3 (A) shows a partial side view of the bush chain 31, and FIG. 3 (B) shows a sectional view thereof. (C)
Shows the state at the time of contact with the guide member. The bush chain 31 corresponds to the roller chain 21 of the above-described embodiment without rollers, and hereinafter, the same members as those of the roller chain 21 will be described with the same reference numerals.

The bush chain 31 is shown in FIG.
As shown in (B), an outer plate 22 having a pair of pin holes 22 a, an inner plate 23 having a pair of bush holes 23 a, and a bush hole 23 of the inner plate 23.
Bush 24 'fitted and fixed to a and this bush 24'
The pin hole 2 of the outer plate 22
2a and the connecting pin 26 fixedly fitted. The bush 24 'may have a thick central portion that engages with the teeth of the sprocket.

In the bush chain 31, a large number of a pair of outer plates 22 and 22 and a pair of inner plates 23 and 23 connected by a bush 24 'are displaced from each other in the longitudinal direction and connected by a connecting pin 26. Formed, bush 2
The connecting pin 26 rotates using 4'as a bearing.

Further, the bush chain 31 is shown in FIG.
As shown in, the outer plate 22 and the inner plate 23 are
The upper end surfaces 22b and 23b and the lower end surface 22 which are parallel to each other, respectively.
It is formed of a substantially oval plate having c and 23c.

First, regarding the positional relationship between the upper end surface 22b and the upper end surface 23b, as shown in FIG. 3A, the outer plate 22 and the inner plate 23 are connected to the centers of the pin hole 22a and the bush hole 23a. With the pitch line 27 arranged in a horizontal straight line, the outer plate 22
The upper end surface 22b of the inner plate 23 has an inner diameter Q1 of the bush 24 ′ and an outer diameter Q2 of the connecting pin 26 that is larger than the upper end surface 23b of the inner plate 23.
And the difference P (Q = Q1−Q2) is 1/2 below, and a step P = (1/2) · Q is generated.

Next, regarding the lower end surface 22c and the lower end surface 23c, the lower end surface 22c of the outer plate 22 is more than the lower end surface 23c of the inner plate 23 in the state of being arranged in a horizontal straight line as in the above. , Inner diameter Q of bush 24
1 and the outer diameter Q2 of the connecting pin 26, Q (Q = Q1-Q
It is located only 1/2 of 2) above, and the step P = (1 /
2) ・ Q occurs.

Bush chain 31 formed in this way
When the upper end surfaces 22b and 23b are in sliding contact with the guide member and travel, as shown in FIG. 3C, the sliding contact causes the inner plate 23 to move downward by the step P and the outer plate 22 to move upward. The end face 22b and the upper end face 23b of the inner plate 23
Are substantially flush with each other, and the upper end surface 22 of the bush chain 31
The entire b and 23b are substantially flush with each other.

Therefore, the upper end surface 2 of the bush chain 31
When the 2b and 23b run in sliding contact with the guide member, the upper end surface 22b of the outer plate 22 and the upper end surface 23b of the inner plate 23 evenly contact the guide member, and the surface pressure between the guide member and the bush chain 21 is reduced. Top surface 2 of both plates
It will be accepted by 2b and 23b.

When the lower end surfaces 22c and 23c travel in sliding contact with the guide member, the sliding contact causes the inner plate 23 to move upward by the step P, so that the lower end surface 22c of the outer plate 22 and the inner plate 23 move. The lower end surface 23c is substantially flush with the lower end surfaces 22c, 23c of the bush chain 31.
The whole becomes almost flush (not shown).

Therefore, the lower end surface 2 of the bush chain 31
When 2c and 23c travel in sliding contact with the guide member, the lower end surface 22c of the outer plate 22 and the lower end surface 23c of the inner plate 23 contact the guide member evenly, and the surface pressure between the guide member and the bush chain 31 is reduced. Lower end surface 2 of both plates
It will be accepted by 2c and 23c.

As a result, the upper end surface 2 of the bush chain 31
When 2b, 23b or the lower end surfaces 22c, 23c run in sliding contact with the guide member, it is possible to prevent abrasion of both end portions of the guide member and prevent increase of friction loss. The load applied to the fitting fixing portion between the pin hole 22a of the plate 22 and the connecting pin 26 can be suppressed, and accordingly, the connecting pin 26 can be prevented from coming off due to weakening of the fitting force, and the bush chain 31 can be prevented from being cut. You can

In each of the above embodiments, the transmission chain having the steps on both the upper end surface and the lower end surface has been described. However, the transmission chain has at least the upper end surface or the lower end surface on the side in sliding contact with the guide member. There may be a step on one side.

[0051]

As described above, in the transmission chain comprising the roller chain or the bush chain of the present invention, the pitch line connecting the outer plate and the inner plate at the center of each pin hole becomes horizontal. If the upper end surface of the outer plate is positioned lower than the upper end surface of the inner plate by 1/2 of the difference between the inner diameter of the bush and the outer diameter of the connecting pin in the arranged state, the upper end surface of the transmission chain is guided. When traveling in sliding contact with the member, the upper end surface of the outer plate and the upper end surface of the inner plate are flush with each other, and the entire upper end surface of the transmission chain can be substantially flush.

Further, in a state in which the outer plate and the inner plate are arranged so that the pitch lines connected at the centers of the pin holes are horizontal, the lower end surface of the outer plate is closer to the inner diameter of the bush than the lower end surface of the inner plate. And the lower end surface of the inner plate when the lower end surface of the transmission chain slides against the guide member and travels when the upper end is half the difference between the outer diameter of the connecting pin and the outer diameter of the connecting pin. And are flush with each other, and the entire lower end face of the transmission chain can be flush with each other.

As described above, since the upper end surface or the lower end surface of the entire transmission chain can be made flush with each other during the sliding contact running, the upper end surface of the outer plate and the guide member or the lower end surface of the outer plate and the guide member. Since the surface pressure between and can be reduced, it is possible to prevent a decrease in the fitting force between the pin hole of the outer plate and the connecting pin, and to prevent the transmission chain from being cut due to the decrease in the fitting force. .

Further, since the upper end surface or the lower end surface of the entire transmission chain can be made flush with each other to eliminate the step, the transmission chain can be smoothly inserted below or below the guide member.

[Brief description of drawings]

FIG. 1 shows a part of a roller chain of Example 1 of the present invention, (A) is a side view, and (B) is a sectional view taken along line XX ′ of (A).

2A and 2B show a moving state of the inner plate, FIG. 2A is a side view, FIG. 2B is a sectional view taken along line XX ′ of FIG. 2A, and FIG.

FIG. 3 shows a part of the bush chain of the second embodiment,
(A) is a side view, (B) is a sectional view taken along line XX 'of (A),
(C) is an explanatory view of a moving state of the inner plate.

FIG. 4 is a side view of a timing transmission mechanism using a transmission chain.

5 is an enlarged view of part F in FIG.

FIG. 6 shows a part of a conventional roller chain, (A)
Is a side view and (B) is a sectional view taken along line YY 'of (A).

7A and 7B show a moving state of the inner plate, FIG. 7A is a side view, FIG. 7B is a sectional view taken along line YY ′ of FIG. 7A, and FIG.

[Explanation of symbols]

1 Timing transmission mechanism 2 and 3 sprockets 4 Roller chain 5 Guide 6 Tensioner 7 Tensioner lever 21 Roller chain 22 outer plate 22a pin hole 22b upper end surface 22c lower end surface 23 Inner plate 23a Bush hole 23b Upper end surface 23c Lower end surface 24 bush 25 roller 26 connecting pin 27 pitch line 31 bush chain 24 'bush Q1 Bushing inner diameter Q2 Connecting pin outer diameter P step

Claims (4)

[Claims] 1. A bush fitted and fixed in a pair of bush holes formed in the inner plate, and a bush fitted in the bush and loosely fitted in a pair of pin holes formed in the outer plate. A transmission chain comprising a roller chain composed of a connecting pin and a roller loosely fitted on the outer periphery of the bush, wherein the outer plate and the inner plate are substantially oval with both parallel upper and lower end surfaces. When the outer plate and the inner plate are arranged so that the pitch lines connecting the centers of the respective pin holes and bush holes are in a horizontal straight line, the upper end surface of the outer plate is above the inner plate. A transmission chain which is located below the end surface by half the difference between the inner diameter of the bush and the outer diameter of the connecting pin. 2. The outer plate and the inner plate are arranged such that the pitch line connecting the centers of the pin holes and the bush holes is arranged in a horizontal straight line, and the lower end surface of the outer plate is more than the lower end surface of the inner plate. 2. The transmission chain according to claim 1, wherein the transmission chain is located above by half the difference between the inner diameter of the bush and the outer diameter of the connecting pin. 3. A bush fitted in and fixed to a pair of bush holes formed in the inner plate, and a bush loosely fitted in the bush and fitted and fixed in a pair of pin holes formed in the outer plate. In a transmission chain including a bushing chain composed of a connecting pin, the outer plate and the inner plate are both formed of a substantially oval plate having an upper end surface and a lower end surface which are parallel to each other. , The pitch line connecting the centers of the pin hole and the bush hole is arranged in a horizontal straight line, the upper end surface of the outer plate is more than the inner diameter of the bush and the outer diameter of the connecting pin from the upper end surface of the inner plate. Difference 1
A transmission chain characterized by being located only 1/2 downward. 4. The lower end surface of the outer plate is lower than the lower end surface of the inner plate in a state in which the outer plate and the inner plate are arranged so that the pitch line connecting the centers of the pin holes and the bush holes is in a horizontal straight line. The transmission chain according to claim 3, wherein the transmission chain is located above by half the difference between the inner diameter of the bush and the outer diameter of the connecting pin.