JPH0781611B2 - Endless belt for transmission - Google Patents

Description

TECHNICAL FIELD The present invention relates to a transmission endless belt, and more particularly to a belt for a continuously variable transmission that is used by being wound around a primary pulley and a secondary pulley composed of a pair of sheaves.

This type of belt is roughly divided into a so-called VAN DOORNE type in which V blocks are continuously mounted on a belt portion where endless thin steel plates are laminated, and a so-called chain type in which link plates are connected by pins. There is.

Further, the chain type uses the pin itself as a frictional force transmission member that comes into contact with the pulley, attaches the frictional force transmission member to the pin, uses the link plate itself as the frictional force transmission member, and transmits friction force to the link plate. There are a member mounted and a member for holding a frictional force transmission member between the pins and transmitting the force by abutting the member and the pin. However, the present invention is directed to a frictional force transmission member between the pins. The present invention relates to a transmission type endless belt that holds a (V block).

(B) Conventional technology Recently, chain type endless belts for transmission have pins,
It has been devised that it is composed of a pair of pin pieces having rolling contact surfaces that are in rolling contact with each other to improve the transmission capacity and durability.

In this structure, it is necessary to prevent relative rotation between each pin piece and the link plate. Conventionally, as the blocking means, for example, as shown in Japanese Patent Publication No. 35-14807, a V-shaped pin piece is used. In which a V-shaped projection is formed on the link plate and the projection is engaged with these engagement grooves, and as shown in Japanese Patent Publication No. 52-35833. A pin piece having a notch and a link plate having a protrusion engaging with the notch. Further, as shown in JP-B-58-3136, the rolling contact surface of the pin piece has a rear surface portion. For example, there is a structure in which a recess is formed so that the pin plate comes into contact with the link plate at two positions apart from each other.

(C) Problems to be solved by the invention Therefore, in the former two cases, stress concentration occurs in the V-shaped engaging groove and the notch portion, and the pin is easily broken, and in the latter case, The presence of the concave portion impairs the rigidity of the pin, and any of them has a problem in durability.

Further, since the V-shaped engaging groove, the notch and the recess are complicated and small in size, it is extremely difficult to manufacture the pin and the link plate, and there is a problem in manufacturing.

Further, all of the above-mentioned conventional devices use the pin itself as the frictional force transmission member, and no consideration is given to the relationship with the V block.

Therefore, according to the present invention, the pin piece is securely locked to the link plate, but the problems in durability and manufacturing are solved, and further, the V block is securely held on the pin and smooth against the pin. It is an object of the present invention to provide an endless belt for transmission, which is bent in the direction of 0 to improve durability and transmission torque capacity.

(D) Means for Solving the Problem The present invention has been made in view of the above circumstances, and is formed at both ends of a large number of link plates 2 as shown in FIGS. 1 and 2, for example. Pin 3 on the pin mounting parts 2a and 2b
An endless belt for transmission, which includes a link row 5 inserted through the endlessly and connected to the link row 5 and V blocks 6 and 7 held and mounted between the adjacent pins. 1, the pin 3 has a rolling contact surface P1 in which the pins 3 are in rolling contact with each other, as shown in FIG. 4, for example.
It consists of 3a and 3b.

Further, these pin pieces 3a (3b) are, for example, as shown in FIG. 7, adjacent to the engagement plane P2 formed of a substantially flat surface on the side opposite to the rolling contact surface P1 and the belt inner diameter side of the engagement plane. First
And a second curved surface P4 on the inner diameter of the belt.
Have.

Further, the pin mounting portions 2a and 2b of the link plate 2 have a plane L1 which is in surface contact with the engagement plane P2 of the pin piece, as shown in FIG. 8, for example.

Then, the V block 6, (7) includes, for example, as shown in FIG. 9, a circumferential contact surface B1 contacting the engagement plane P2 or the first curved surface P3 of the pin piece and a second curved surface of the pin piece. The groove 6a (7a) having a radial contact surface B2 that contacts P4 is provided.

(E) Operation Based on the above configuration, the endless belt 1 is used, for example, by being wound around both primary and secondary pulleys. At this time, a force is applied from the primary pulley to the V blocks 6 and 7 of the belt 1 due to frictional contact. It is further transmitted from the V block to the link row via the pin 3, and is transmitted from the pin 3 to the V blocks 6 and 7 on the secondary pulley side, and is transmitted from the V block to the secondary pulley by frictional contact. It

At the pulley portion, the belt 1 bends in accordance with the effective diameter of the pulley, but the pair of pin pieces 3a, 3b make rolling contact with the rolling contact surface P1 and make a smooth bend.

Further, the pin pieces 3a and 3b roll on each other and abut on the contact surfaces P1 and P1, so that the engagement plane P2 on the opposite side of the pin pieces 3a and 3b contacts each other.
The pin pieces 3a, 3b and the link plate 1 are integrally locked by being pressed against the plane L1 of b) and pressing and contacting the planes P2, L1.

Further, the V blocks 6 and 7 receive a force in the belt outer diameter direction due to the force received from the pulley at the pulley portion and the centrifugal force at the belt traveling portion between the pulleys, but the groove 6
The circumferential contact surface B1 of a, 7a abuts on the engagement plane P2 or the first curved surface P3 of the pin piece, and the radial contact surface B2 thereof is the second.
The V block is held stably by abutting against the curved surface P4 of the V block and supporting it at two points on the belt inner diameter side and the belt running line side.

Furthermore, when the belt 1 is bent from the straight state,
6, 7 rotate relative to the pin 3, and the circumferential contact surface B1 shifts its abutting position from the engagement plane P2 of the pin piece to the first curved surface P3, but in particular, the first curved surface P3 If the cross-sectional shape of is a circular arc having a predetermined radius and the cross-sectional shape of the engagement plane P2 is a tangent to the circular arc, the contact position transition of the circumferential contact surface smoothly transitions.

(F) Example Hereinafter, an example in which the present invention is embodied will be described with reference to the drawings.

As shown in FIGS. 1 to 3, the continuously variable transmission belt 1 includes a link row 5 in which a large number of link plates 2 are connected by pins 3 and a first row mounted on the link row 5. V
It consists of a block 6 and a second V block 7. The link plate 2 has pin holes (mounting parts) 2a, 2b at both ends thereof.
Are formed, and the pins 3 are inserted into these pin holes 2a and 2b to alternately connect the link plates 2 to form a link row 5. Further, as shown in FIGS. 4 and 5, the pin 3 is composed of a pair of pin pieces 3a, 3b having rolling contact surfaces P1, P1 in rolling contact with each other. 3b are inserted into the pin holes 2a and 2b so that their rolling contact surfaces are aligned with each other, and the pin 3 is formed to be longer than the width of the link row 5 by a predetermined amount (see FIGS. 2 and 3). . On the other hand, the first and second V blocks 6 and 7 have holes 6b and 7b into which the link row 5 is inserted, and both left and right side surfaces thereof are tapered surfaces 6c and 7c capable of contacting the pulley. Further, as shown in FIG. 6, concave grooves 6a and 7a for accommodating the pins 3 are formed on the front and rear side surfaces thereof, respectively. Further, taper surfaces 6d and 7d are formed on the front and rear one side surfaces of the lower portions of the V blocks 6 and 7, so that the V blocks 6 and 7 can be bent when the link row 5 is bent.
The recessed grooves 6a, 7a of the locking groove 6e, which has a predetermined radius,
7e is formed (see FIG. 9 (c)). Then, in the first and second V blocks 6 and 7, the link row 5 is fitted and inserted into the hole portions 6b and 7b, and the adjacent pins 3 are recessed into the concave grooves 6a and 7b, respectively.
The V-blocks 6 and 7 are held and held by abutting and engaging with a so that the other side faces of the V-blocks 6 and 7 abut each other.
The locking pieces 9 are locked in the locking grooves 6e, 7e of the above to prevent the pin 3 from coming off.

Then, the pin piece 3a or 3b (only one of the pin pieces 3a will be described below because the pin piece is configured to be line-symmetrical)
As shown in FIG. 7 (b), an engaging flat surface P2 formed of a flat surface is formed on the opposite side of the rolling contact surface P1, and the inner diameter side of the engaging flat surface P2 has a side surface shape ( A first curved surface P3 having an arc whose cross-sectional shape is the same) centered on a predetermined position O3 is formed. Further, the center position O3 of the first curved surface P3 is located at the intersection of the rolling contact surface P1 and the line l-l passing through the contact plane a of the curved surface P3 and the contact point a of the curved surface P3 and orthogonal to the engaging plane. The tangent line at the contact point a of the arc forming P3 becomes the engagement plane P2. Further, the rolling contact surface P1 also has a side surface shape (cross-sectional shape) of an arc centered at a predetermined position O1,
The center position O1 of the arc is located on the line l-l.
Further, the belt inner diameter portion, that is, the bottom portion of the pin piece 3a is a second curved surface P4 constituted by an inner arc surface having a large radius, and the curved surface P4 is provided with a rolling contact surface P1 and a first curved surface P1 through a predetermined R surface. It is in contact with the curved surface P3 of 1. Further, a third curved surface P5, which is an arcuate surface having a larger radius of curvature than the first curved surface P3, is formed in a portion contacting above the engagement plane P2,
The other end of the curved surface P5 is in contact with the upper end of the rolling contact surface P1 via a predetermined R surface.

On the other hand, the link plate 2, as shown in detail in FIG.
Pin holes 2a and 2b are formed at both ends thereof, respectively.
Since these pin holes 2a and 2b have a line-symmetrical shape, only one pin hole 2a will be described below. Pin hole
A first flat surface L1 formed of a flat surface that joins with the engagement flat surface P2 of the pin piece is formed at an outer portion of the plate 2a, that is, a portion where a tensile force acts between the pin 3 and the pin 3 and further above it ( Adjacent to (belt outer diameter side), the third curved surface P5 of the pin piece
And a first curved surface L2 formed of an arcuate surface having substantially the same radius as that of the first curved surface P1 and a portion adjacent to the lower side of the first flat surface L1 (belt inner diameter side), that is, the first curved surface P3 of the pin piece 3a. A second curved surface L3 having a radius substantially equal to or slightly larger than the radius of the curved surface P3 is formed in the corresponding portion.
Further, the bottom plane L4, the inner plane L5, and the predetermined radius are set so that the bottom of the pin hole 2a and the inner side of the link, that is, the portion where no tensile force acts between the pin 3 and the pin 3 do not interfere with the pin pieces 3a and 3b. R portions L6 and L7 are formed. Therefore, the pin hole 2a of the link plate 2 has the first plane L1 and the first curved surface L2.
While positively making surface contact with the engaging plane P2 and the third curved surface P4 of the pin piece 3a, the second curved surface L3 and the bottom plane L4 are the first curved surface P3 and the second curved surface P4 of the pin piece. The inner planes L5, R portions L6, L7 are always separated from each other in order to prevent interference with other pin pieces 3b.

In addition, the first V block 6 has a structure shown in FIGS.
As shown in detail in (c), the recessed grooves 6a, 6 penetrate through the side tapered surface 6c from the hole 6b at substantially the center of the left and right legs 6f, 6f.
a is formed, and further, in the middle of the concave groove 6a, a locking groove 6e having a predetermined width and an arc having a radius centered on a predetermined position O5 is formed. The concave groove 6a is located at substantially the same level as the contact point b between the bending taper surface 6d and the parallel surface 6g,
Further, a portion facing the opening is a first plane B1 which is a substantially vertical surface which constitutes a circumferential contact surface, and the lower portion (belt inner diameter side) thereof is a radial contact surface which is substantially formed. It is a second plane B2 which is a horizontal plane. Furthermore,
Above the first plane B1 is the pin piece 3a from the second plane B2.
A third plane B3 is formed at a distance longer than the vertical length of the above, and a predetermined R plane is interposed between the first plane B1 and the second and third planes B2, B3. Therefore, in the V block 6, the first plane B1 thereof is the engagement plane P2 of the pin piece 3a.
(Belt straight state) or the first curved surface P3 (belt bent state), and the second plane B2 thereof contacts the third curved surface P4 of the pin piece.

As shown in FIG. 10, the second V block 7 has a groove 7a formed on the opposite surface side to the first V block 6, that is, on the side where the bending taper surface 7d is located. Since it is the same as the first V block 6 except for the difference, the same reference numerals are given and the description thereof is omitted.

Next, the operation of this embodiment will be described.

The continuously variable transmission belt 1 is used by being wound around a continuously variable transmission including a pair of variable diameter pulleys. On the primary pulley side, the first and second V blocks 6 and 7 rub against the pulleys. The contacting torque is transmitted from the pulley and further transmitted to the link row 5 via the pin 3. Specifically, the force acting on the second V block 7 is transmitted to the first block 6 by contact with the first V block 6, and the force acting on the first V block 6 is directly caused by the concave portion. Based on the contact between the first plane B1 of the groove 6a and the engagement plane P2 of the pin piece 3a or the first curved surface P3, it is transmitted to the pin piece 3a and further the rolling contact surface of the pin piece 3a.
The contact between P1 and the rolling contact surface P1 of the other pin piece 3b is transmitted to the pin piece 3b, and the engagement plane P2 and the third curved surface P5 of the pin piece 3b and the first pin hole 2b of the link plate 2 Plane of
Link plate 2 due to surface contact with L1 and first curved surface L2
Be transmitted to. In this way, the tensile force acts on the tight side of the belt 1. Also, on the secondary pulley side,
On the contrary, the pulling force from the link row 5 is transmitted to the first and second V blocks 6 and 7 via the pin 3, and further the frictional force between the tapered surfaces 6c and 7c of the V blocks 6 and 7 and the pulley surface. Is transmitted to the secondary pulley by.

At this time, the pin pieces 3a, 3b are engaged with each other on the engagement plane P2 based on the pressing force acting on the rolling contact surface P1 from the other pin piece 3b, 3a.
Comes into close contact with the first plane L1 of the pin holes 2a and 2b, and is thereby locked integrally with the link plate 2. Furthermore, the force acting on the pin pieces 3a, 3b from the rolling contact surface P1 is not only the surface contact between the engaging plane P2 and the first plane L1, but also the surface between the fourth curved surface P5 and the second curved surface L2. Due to the surface contact over these large areas, the force from the pin pieces 3a, 3b causes the pin hole 2 of the link plate 2 to come into contact.
It is carried by a and 2b.

Further, the first and second V blocks 6 and 7 have tapered surfaces 6c and 7c.
Due to the force from the pulley surface acting on the belt and the centrifugal force, the belt is always subjected to a force in the radial direction of the belt, and the second (horizontal) plane B2 of the concave grooves 6a, 7a thereof is the second of the pin pieces 3a, 3b. The first (vertical) plane B1 thereof abuts the engaging plane P2 or the first curved surface P3 of the pin piece and is stably held by the two line contact. At this time, a large pressure acts on the contact surfaces B1 and P4, B2 and P2 or P3 based on the force transmission from the V block 6,7 to the pin 3 or from the pin 3 to the V block 6,7. Since the pressure is a contact between a curved surface and a flat surface, it has a relatively low value.

Further, when the belt 1 is introduced into the pulley, the link row 5 changes from a straight state to a curved state, but at this time, the pin pieces 3a and 3b, which are bent portions, are smoothly bent by the rolling contact surfaces P1 and P2.
Further, due to the bending, the first and second V blocks 6 and 7 are brought into contact with the first curved surface P3 from the state in which the first plane B1 of the first and second V blocks 6 and 7 is in contact with the engagement plane P2 of the pin pieces 3a and 3b. Move to touch. At this time, since the first curved surface P3 is formed by the contact circle of the engagement plane P2, the first curved surface P3 moves smoothly and no partial load is applied.

In the above embodiment, the third curved surface P5 is a curved surface made of an arc, but this may be another curved surface such as an involute or a curved surface or a plane whose center is infinitely distant, and the engaging plane P2 is also accurate. However, it may be a curved surface that is almost flat, such as an arc having an extremely large radius.

Further, in the above-described embodiment, the pin 3 is retained by the locking piece 9, but the V-blocks 6 and 7 may be integrally formed with a protrusion for retaining the pin by pressing. A third V block for pin locking may be interposed between the two V blocks.

(G) Effect of the Invention As described above, according to the present invention, the pin pieces 3a, 3b are provided.
Engages the engaging plane P2 with the plane L1 of the pin mounting portions 2a and 2b and is integrally locked to the link plate 2, so that the surface pressure based on the pressing force from the rolling contact surface P1 is flat. Carry,
The pin piece can be reliably held on the link plate 2, and the concentrated stress does not act, so that the durability of the pin 3 and the link plate 2 can be improved.

Further, in the V blocks 6 and 7, the radial contact surface B2 of the concave grooves 6a and 7a abuts on the second curved surface P4 of the pin piece, and the circumferential contact surface B1 thereof is the engagement plane P2 of the pin piece. Since it abuts on the first curved surface P3, the V block is moved in the direction of travel and in the radial direction.
It can be held securely in place. Further, if the circumferential and radial contact surfaces B1 and B2 of the V block are formed as flat surfaces, the surface pressure at the contact portion can be reduced and the durability of the V blocks 6 and 7 and the pin 3 can be improved. In addition, the transmission torque capacity of the belt 1 can be improved.

Also, the pin pieces 3a, 3b, the pin mounting portion 2a of the link plate 2,
Since the concave grooves 6a and 7a of the 2b and the V blocks 6 and 7 have a simple shape including a flat surface and a curved surface, they can be easily manufactured by press working, drawing working or mechanical working.

Further, when the engaging plane P2 of the pin pieces 3a, 3b is constituted by the tangent line of the first curved surface P3, the first plane B1 of the V blocks 6, 7 smoothly slides from the engaging plane to the first curved surface P3. In addition to the fact that the pin pieces 3a, 3b can roll over and contact each other at the contact surfaces P1, P1, the bending of the belt 1 can be made smooth and the transmission efficiency of the belt 1 can be improved. It is possible to improve the durability of the belt 1 by preventing the unbalanced load from partially acting.

In addition, the third curved surface P5 of the pin pieces 3a, 3b is configured by a curved surface having a larger radius of curvature than the first curved surface P3, and the pin mounting portions 2a, 2
If the first curved surface L2 of b is configured so as to substantially match the curved surface P5, the pressing force can be carried by the surface contact having a large area,
The transmission torque capacity of the belt 1 can be improved, and the durability of the pin 3 and the link plate 2 can be improved.

Furthermore, the center position O1 of the rolling contact surface P1 of the pin pieces 3a, 3b is
When the belt 1 is located on the line l-l that passes through the contact point a between the engagement plane P and the first curved surface P3 and is orthogonal to the engagement plane P2, the belt 1 is in rolling contact regardless of whether the belt 1 is in a straight state or a bent state. Surface P1
Force can always be reliably applied to the engaging plane P2 and the plane L1 of the pin hole to lock the pin hole, and, when the belt 1 is bent, the contact position of the first plane B1 of the V block. Can be smoothly transferred from the engagement plane P2 of the pin piece to the first curved surface P3.

[Brief description of drawings]

FIG. 1 is a partially sectional side view showing an endless belt for transmission according to the present invention, FIG. 2 is a horizontal sectional plan view thereof, and FIG. 3 is a longitudinal sectional front view thereof. FIG. 4 is a side view showing the link row in a straight line state,
FIG. 5 is a side view showing the link row in the bent state, and FIG. 6 is a side view showing a state in which the V block is mounted. Further, FIG. 7 is a view showing a pin piece, (a) is a front view,
(B) is an enlarged side view. 8 is a side view showing the link plate, FIG. 9 is a view showing the first V block, (a) is a front view, (b) is its bb sectional view, and (c) is the same. It is c-c sectional drawing. FIG. 10 is a sectional view showing the second V block. 1 ... endless belt for transmission (for continuously variable transmission), 2 ... link plate, 2a, 2b ... pin mounting part (hole), 3 ... pin, 3a, 3b ... pin piece, 5 ... link Row, 6 ... (First
) V block, 6a ... concave groove, 7 ... (second) V block, 7a ... concave groove, P1 ... Rolling contact surface, P2 ... engaging plane, P3 ... first curved surface, P4: second curved surface, P5: third curved surface
Curved surface, L1 ... (first) plane, L2 ... (second) curved surface, L3 ... third curved surface, B1 ... circumferential contact surface (first plane), B2 ... radial direction Contact surface (second plane).

Claims (6)

[Claims] 1. A link row formed by inserting a pin into end mounting portions formed at both ends of a large number of link plates and endlessly connected to the link row, and being held between adjacent pins in the link row. In the endless belt for transmission, the pin comprises a pair of pin pieces having rolling contact surfaces that make rolling contact with each other, and these pin pieces have rolling contact surfaces. On the opposite side, there is an engaging flat surface made of a substantially flat surface, and on the inner diameter side of the belt adjacent to the engaging flat surface, there is a first curved surface, and on the inner diameter portion of the belt there is a second curved surface. The pin mounting portion has a flat surface that comes into surface contact with the engagement flat surface of the pin piece, and the V block has a circumferential contact surface that comes into contact with the engagement flat surface or the first curved surface of the pin piece and the second contact surface. Radial contact surface that contacts the curved surface of Consisting comprises a groove having, power transmission endless belt, characterized in that. 2. The endless belt for transmission according to claim 1, wherein the circumferential contact surface and the radial contact surface of the V block are flat surfaces. 3. The cross-sectional shape of the first curved surface of the pin piece is an arc having a predetermined radius, and the cross-sectional shape of the engagement plane is a tangent to the arc. Endless belt for transmission as described. 4. A third pin piece having a radius of curvature larger than that of the first curved surface, adjacent to the belt outer diameter side of the engagement plane.
4. The power transmission according to claim 3, wherein the pin mounting portion of the link plate has a curved surface and the portion corresponding to the third curved surface is a curved surface having substantially the same radius of curvature. Endless belt. 5. The cross-sectional shape of the rolling contact surface of the pin piece is
2. A circular arc having a predetermined point as its center, and the predetermined point is located on a line passing through a contact point between the engagement plane and the first curved surface and orthogonal to the engagement plane. Endless belt for transmission as described. 6. The V-block comprises first and second V-blocks each having the groove on one side surface and abutting each other on the other side surface. Endless belt for transmission.