JP5028779B2 - Endless belt for transmission and belt type continuously variable transmission using the same - Google Patents

Description

  The present invention relates to a transmission endless belt in which link plates are connected by a joint pin and a belt-type continuously variable transmission using the belt, and more particularly, a technique for reducing noise and vibration caused by the belt contacting a pulley. About.

  Recently, a belt-type continuously variable transmission (hereinafter referred to as CVT) has been attracting attention as a transmission mounted on an automobile. As an endless belt for the continuously variable transmission, a link-type belt in which a link plate is connected by a joint pin is known. It has been. In the link type belt, pins are intermittently brought into contact with pulleys, and a sound having a frequency corresponding to the contact cycle is generated. However, the sound becomes annoying noise for a person having a peak at a predetermined frequency. However, this is a problem particularly when the CVT is mounted on an automobile.

  Conventionally, multiple pin lengths are provided (randomized), and the period in which these pins contact the pulleys is dispersed in multiples, and the peak frequency is dispersed to reduce harsh noise (white noise). A link type endless belt has been proposed (see, for example, Patent Document 1). The endless belt has a long pin in contact with the outer diameter side of the pulley, a short pin in contact with the inner diameter side of the pulley, and the contact timing with the pulley differs between the long pin and the short pin, thereby reducing white noise. ing.

  In addition, the pin is divided into two pieces, each pin piece is connected to the link plate of each link in a non-rotatable manner and is in rolling contact with each other, and at least one end face of the pin piece (swing piece) is A link-type endless belt has been proposed that has a shape different from that of a flat surface both in the radial direction and in the circumferential direction (see Patent Document 2). It is also conceivable to provide a plurality of types of end face shapes of the pin pieces that come into contact with the pulleys and change the contact timing of the pins to the pulleys to generate white noise.

JP-A-63-53337 JP 2000-230606 A

  Even if multiple types of pins with different pin lengths and pin end face shapes are provided and the contact timing to the pulley is changed, the peak frequency can be dispersed and white noise can be achieved. Mutual relationships have not been fully studied.

  Therefore, the applicant of the present invention sequentially inserts between the opposing wall surfaces of the pulley, and the engaging means (for example, a pin) for transmitting torque between the pulley and the endless belt is subjected to an impact when the pulley is inserted into the pulley. A first group of engaging members that generate vibrations with a fixed period with respect to rotation and a second group of engaging members that generate vibrations with the same period shifted to cancel the fixed period of vibrations are mixed. An endless belt for power transmission was proposed (Japanese Patent Application No. 2004-173267; not disclosed at the time of filing this application). Thereby, the vibration of the frequency by the engagement member of the 1st group and the frequency by the engagement member of the 2nd group mutually cancels, and generation of noise is reduced.

  Specifically, when the pitch in the belt running direction is different, the second group of engaging members has the same length in the belt width direction as the first group of engaging members, In combination with the vibrations generated by the engaging members, the vibrations with a phase shift of 120 degrees canceling out the vibrations with a constant period are generated at a position twice the pitch in the belt traveling direction between the first group of engaging members. The arrangement is assumed to be arranged.

  Similarly, when the pitch in the belt running direction is made different, the second group of engaging members have the same length in the belt width direction as the first group of engaging members, and the first group of engaging members In order to generate vibrations that are 180 degrees out of phase with respect to vibrations generated by the first group, the first group of engaging members are arranged at a position that is 1.5 times the pitch in the belt running direction.

Next, in the case where the lengths in the belt width direction are different, the engagement member is arranged such that the arbitrary engagement member is brought into contact with the next engagement member after the arbitrary engagement member contacts the pulley. The length of the engaging member is set so that the virtual pitch L defined as the linear distance that the member moves includes L ₁ = L and L ₂ = 1.5L.

Similarly, when the lengths in the belt width direction are different from each other, the engagement member moves between any engagement member contacting the pulley and the next engagement member. The length of the engaging member is set so that a virtual pitch L defined as a linear distance includes L ₁ = L, L ₂ = 2 / 3L, and L ₃ = 4 / 3L.

  In any of the above cases, it is effective that the virtual pitch has the length relationship when the transmission ratio of the continuously variable transmission is a predetermined value.

  Further, it is more effective if the virtual pitch has the above-mentioned length relationship at a gear ratio of the continuously variable transmission greater than 1.0.

  In any of the above cases, the endless belt is constituted by a chain belt in which link plates are connected endlessly by pins, and the first group of engaging members and the second group of engaging members are formed by the pins. It is effective to be configured.

  In this case, when the pin constituting the joint is a pair of pin pieces, the virtual pitch is a distance from one pin piece of a pair of pins to one pin piece of a pair of adjacent pins, Or it is defined as the distance from the center position of a pair of pins to the center position of the next pair of pins.

  According to the above configuration, by providing a plurality of mutual distances or lengths in the belt width direction between the first group of engagement members and the second group of engagement members, the timing at which the engagement members contact the pulley is shifted. This timing is determined by the pitch interval, the pulley rotation speed, the gear ratio, that is, the rotation radius of the belt when the belt is sandwiched between the pulleys.

  Therefore, when the actual pitch or the virtual pitch L includes L and 1.5L, the frequency at which the engaging means periodically contacts (collises) with the pulley when the engaging member continuously contacts the pulley at the pitch L. The pulley and belt are vibrated at (the frequency is set to H), and noise of the frequency and higher frequency is generated. On the other hand, when the engaging means contacts the pulley at a pitch of 1.5 L, a contact impact is applied to the pulley and the belt at a position where the phase is shifted by 180 degrees with respect to the vibration of the frequency H. Thereafter, when the engaging means comes into contact with the pulley again at the pitch L, a vibration having an antiphase with the frequency H is given to the vibration with the original frequency H. That is, by applying antiphase vibrations at the same frequency, the antiphase vibrations cancel each other, so that the belt and pulley vibrations can be suppressed.

  On the other hand, when the actual pitch or the virtual pitch includes 2 / 3L and 4 / 3L, if the vibration frequency when the engaging means contacts the pulley at the pitch L is H as in the above case, this vibration In contrast, when the engaging means and the pulley come into contact with each other at a pitch of 2/3 L, the pulley and the engaging means come into contact with each other at a position whose phase is shifted by -120 degrees with respect to the vibration of the frequency H. After that, when the engaging means and the pulley come into contact again at the pitch L, a vibration deviated by −120 degrees with respect to the original vibration occurs at the frequency H. Similarly, when the engaging means and the pulley come into contact with each other at a pitch L after the engaging means and the pulley come into contact with each other at a pitch of 4 / 3L, a vibration whose phase is shifted by +120 degrees at the frequency H is generated. That is, vibrations that are 120 degrees out of phase with each other at the frequency H are generated. In this way, vibrations whose phases are shifted from each other by 120 degrees cancel each other out, and as a result, vibrations can be suppressed.

  As described above, when the belt is formed so that the pin pitch has L, 1.5L, or L, 2 / 3L, 4 / 3L, a plurality of vibrations having phases that cancel each other out as vibration due to contact between the belt and the pulley As a result, vibration can be suppressed.

If the pitch lengths L ₁ and L ₂ between the pins are set to L ₂ = 2L ₁ , the linear distance (virtual pitch) by which the previous pin moves from the contact of a certain pin to the contact of the next pin to be able to set a 1.5 L _1, 'When _{L 1} = 2 / 3L 1' again _{L 1} the _{1.5L 1, L 2 = 2L 1} = 4 / 3L 1 ' becomes, _{L 1'} a As a reference, a pitch interval of 2 / 3L ₁ ′, 4 / 3L ₁ ′ can be obtained.

  Here, for example, the basic pitch L is 8 mm, the difference between the pin length of the long pin and the pin length of the short pin is 50 μm, and the angle (pulley angle) θp formed with respect to the plane perpendicular to the axis of the pulley contact wall surface is In the case of 10 degrees, as shown in FIG. 14, the virtual pitch, which is the distance until the adjacent pin contacts the pulley, changes with respect to the radius at which the pin is sandwiched between the pulleys (the detailed calculation formula is (See Japanese Patent Application No. 2004-173267). That is, when the pin length is randomly arranged (pin length random), for example, an endless belt composed of a short pin (short pin) and a long pin (long pin) has a smaller random pitch difference as the pulley radius is smaller. Therefore, when contacting the pulley in the order of short pin, long pin, short pin, the virtual pitch increases as the pulley effective radius increases, and when contacting the pulley in the order of long pin, short pin, long pin, the pulley effective radius increases. As the virtual pitch becomes smaller, it is difficult to maintain the meshing at the frequency composed of the phase differences that cancel each other over a wide speed ratio.

  Similarly, when the pin end surface has a different shape and the position where the pin contacts the pulley is made random in the vertical direction or the belt traveling direction, the virtual pitch changes with the change in the gear ratio. For example, the shape of the pin end surface is such that the belt running direction is a plane parallel to the pulley wall surface (plane of the pulley angle θp), the pulley radial direction is a predetermined arc surface, and the center of the arc is set to the upper or lower position. When the upper and lower random pins are used as the contact pin and the lower contact pin, the virtual pitch changes depending on the effective pulley radius.

  As described above, since the pitch varies depending on the gear ratio regardless of whether the pin length is random or the contact position random depending on the pin end shape, the first group of engaging members and the first member It is difficult to maintain the relationship that causes the two groups of engaging members to generate vibrations that are out of phase with the same period in order to cancel vibrations with a constant period.

  Therefore, the present invention provides a shape of the end face of the pin so as to reduce a change in pitch change amount (random pitch difference) due to a gear ratio in a random pitch transmission endless belt such as a random pin length or a random pin contact position. Therefore, it is an object of the present invention to provide an endless belt for transmission and a belt type continuously variable transmission using the same.

In the present invention, an engagement means (4) is configured to be endless by connecting a large number of link plates (2) with joint pins (3), and to transmit torque by contacting the sheave wall surface (11) of the pulley. In the transmission endless belt (1),
The engagement means includes at least two types of engagement members having different timings of contact with the sheave wall surface (11), and at least two types of engagement members of the different types sequentially contact the sheave wall surface. Composing a random pitch,
The shape of the end surface (4a) of the engagement member that contacts the sheave wall surface so as to cancel out the difference in the random pitch that changes corresponding to the pulley effective radius formed by the position where the engagement member contacts the sheave wall surface. Is formed such that the contact position of the end surface with the sheave wall surface is changed corresponding to the pulley effective radius.

  The engaging means includes a first group of engaging members that generate a constant period of vibration by contact with the sheave wall surface, and a first group of vibrations that are out of phase with the same period so as to cancel the constant period of vibration. It is preferable to mix two groups of engaging members.

Further, the engaging member comprises a contact with roll rolling surface to each other (4b, 5b) one pin piece of the joint pin consisting of a pair pins piece (4,5) with (4).
It is preferable that the pin piece (4) on the rear side in the belt running direction of the pair of pin pieces constitutes the engaging member that contacts the sheave wall surface.

Specifically, both end surfaces (4a) of the pin piece (4) constituting the engaging member have an arc surface (R) that is curved in the vertical direction of the belt, for example, as shown in FIG.
As shown in FIG. 8, for example, as shown in FIG. 8, the contact straight line closest to the sheave wall surface of the circular arc surface is arranged at an upper contact pin arranged at a relatively upper part of the both end faces and at a relatively lower part of the both end faces. It has two types of pin pieces with the lower contact pin, that is, the contact straight line is the other pin with respect to one pin piece (upper contact pin) of the two types of pin pieces constituting the engaging means. The piece is placed in the lower part.
As contact straight of the upper contact pin (one pin pieces) (Gu ') is, the lower contact pin contact linear (other pin pieces) (Gd' facing down relatively forward with respect to) Inclined.

Further, both end surfaces (4a) of the pin piece (4) constituting the engaging member have arcuate surfaces (R) curved in the belt vertical direction,
There are two kinds of pin pieces with different lengths of the long pin and the short pin, that is, the two kinds of pin pieces, one of which is a long pin longer than the other and the other is a short pin shorter than the other,
As shown in FIG. 12, for example, as shown in FIG. 12, the contact straight line closest to the sheave wall surface of the arcuate surface is downward in the forward direction relative to the long pin (Gl ′). Inclined to become.

The belt-type continuously variable transmission also includes a primary pulley (10) having a movable sheave (13) having a sheave wall surface (11) and a fixed sheave (12) each capable of contacting a transmission endless belt,
A secondary pulley having a movable sheave and a fixed sheave each having a sheave wall surface that can contact the endless belt for transmission;
The wound over the primary pulley and the secondary pulley, front includes a Kiden dynamic endless belt (1), a,
By moving the movable sheave closer to or away from the fixed sheave, the pulley effective radii of the primary pulley and the secondary pulley are changed.

  In addition, although the code | symbol in the said parenthesis is for contrast with drawing, it does not have any influence on the structure of a claim by this.

According to the present invention, the shape of the end face of one pin piece that serves as the engagement means of the joint pin made of a pair of pin pieces is set to the pulley so as to cancel out the difference in random pitch that changes corresponding to the pulley effective radius. Since the contact position of the end surface with the sheave wall surface is changed corresponding to the effective radius, a desired random pitch difference can be maintained regardless of the effective pulley radius with which the engaging member contacts.

The engaging means includes a first group of pin pieces that generate a constant period of vibration and a second group of pin pieces that generate a phase-shifted vibration of the same period in order to cancel the constant period of vibration. Thus, the above relationship can be maintained over a predetermined gear ratio, and the generation of vibration and noise can be reduced.

If the engaging means is a joint pin, particularly a pin piece on the rear side of the joint pin composed of a pair of pin pieces, the above-described desirable relationship can be maintained with a simple configuration.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present invention, the front-rear direction of the transmission endless belt means the running direction of the belt and the length direction of the belt, which are the horizontal direction of the horizontal portion of FIG. 1 and the horizontal direction of the plane of FIG. The vertical direction is the vertical direction of the paper in the horizontal portion of FIG. 1, and the upward direction means the belt wound around the pulley and the radial outer side as well as the upper half of the belt between the pulleys, The downward direction is the opposite direction, the belt width direction and the left-right direction mean the length direction of the pin, the direction perpendicular to the paper surface in FIG. 1 and the vertical direction on the paper surface in FIG. The direction is the right direction when viewed from the belt traveling direction α, that is, the downward direction in the drawing of FIG. 2, and the left direction means the opposite direction.

  As shown in FIGS. 1 and 2, the transmission endless belt 1 is formed in an endless shape by connecting a large number of link plates 2 in the front-rear direction with joint pins 3. At a joint pin 3 in which a first link L1 composed of four link plates 2 and a second link L2 composed of, for example, five link plates 2 which is one more than the first link penetrate in the width direction. They are connected alternately.

  The link plate 2 has the same shape (may be different shapes) in both the first link L1 and the second link L2, and has an opening 7 having a predetermined shape. On the other hand, the joint pin 3 is composed of a pair of divided pin pieces 4 and 5 having rolling surfaces 4b and 5b that come into contact with each other, and surfaces 4c and 5c opposite to the rolling surfaces of these pin pieces are formed. A pair of pin pieces are seated on the link plates 2 of the first link L1 or the second link L2 in a non-rotatable manner in close contact with both end faces 8, 9 of the opening 7. In addition, as the transmission endless belt that is the subject of the present invention, for example, the belts disclosed in JP-A-10-122307, JP-A-8-31725, and the gazette described in the specification thereof are included. See these publications.

  As shown in FIG. 2, the pair of pin pieces 4, 5 is shorter than the pin piece 5, which is the rear side of the belt running direction α. Therefore, in the endless belt 1, only the rear pin piece 4 comes into contact with the sheave wall surface 11 of the pulley 10 partially shown in FIG. 3, and transmits power to and from the pulley. Specifically, the endless belt 1 is used by being wound around a primary pulley 10 and a secondary pulley, each of which is composed of a fixed sheave 12 and a movable sheave 13, and includes a belt type endless belt composed of these endless belt 1, primary pulley and secondary pulley. The step transmission is suitable for use in a transmission for a vehicle, for example, in which a primary pulley is linked to an engine and a secondary pulley is linked to a drive wheel.

  The rotation of the primary pulley is transmitted to the rear pin piece 4 by contact with the sheave wall surface 11 and further to the front pin piece 5 constituting a pair of joint pins 3 with the pin piece. It is transmitted by pressing through 5a and pulls each link plate 2 ... of one set of links L1 or L2. Similarly, the front pin piece 5 is pressed from the rear pin piece 4 and is further brought into contact with the sheave wall surface of the secondary pulley via the endless belt 1 formed by pulling on the link plate 2 of each link L1, L2. The rotation is transmitted to the secondary pulley via the rear pin piece 4. At this time, the primary pulley and the secondary pulley change the effective radius with which the endless belt 1 of each pulley contacts by changing the distance between the movable sheave in the axial direction and the fixed sheave. The step transmission can transmit rotation by changing continuously. Further, when the endless belt 1 is engaged with each pulley or separated from each pulley, the links L1 and L2 adjacent to each other in the front-rear direction are bent, and the bending is a pair of pins constituting the joint pins 3 described above. The pieces 4 and 5 are bent smoothly by rolling on the rolling surfaces 4b and 5b.

  And each pin piece 4 of the endless belt 1 bites into the sheave wall surface 11 of each pulley, thereby generating periodic noise. It is a premise of the present invention that the end face shape of the pin piece 4 in contact with the sheave wall surface is set to a predetermined shape so as to turn the periodic noise into white noise. The presupposed invention will be described first. . The presupposed invention has already been filed by the present applicant as Japanese Patent Application No. 2004-230809, which has not been disclosed at the time of filing this application.

  The shape of both end faces 4a, 4a that contact the sheave wall surface 11 of the pin piece 4 is a curved surface that curves in the vertical direction (direction perpendicular to the belt running direction α) as shown in FIG. The sheave wall surface 11 of the pulley 10 has a pulley angle of a predetermined angle θp with respect to a plane perpendicular to the pulley axis, and both end surfaces 4a of the pin pieces 4 contacting the sheave wall surface are also from the pulley angle θp. A circular arc surface R that is curved in the vertical direction with respect to the reference plane is formed, and the circular arc surface R has a cylindrical shape that is formed by the same arc in the longitudinal direction of the belt. . That is, as shown in FIG. 3A, both end surfaces 4a of the pin piece 4 are arcuate surfaces having a predetermined radius R centered on a predetermined position P above the center position in the vertical direction of the pin piece 4, and As shown in FIG. 3B, the radial position P of the arc surface is a linear G in the front-rear direction, and the arc surface R has a cylindrical shape. Accordingly, as shown in FIG. 3 (C), the sheave wall surface 11 at a straight line G ′ that is parallel to the straight line G that is the center line in a side view and shifted downward by a predetermined amount at the pin piece both end faces 4a. To touch.

  In the prior application invention, as described above, both end surfaces 4a of the pin piece 4 have a cylindrical shape with the central straight line G and the contact straight line G 'being parallel to each other, and the central portion of the pin piece 4 in the vertical direction. In contact with the sheave wall 11. The pin piece 4 which is a rear pin piece is in rolling contact with the front pin piece 5 constituting the pair of joint pins 3 and corresponds to the bending of the links L1 and L2. Therefore, the inclination of the pin piece 4 differs according to the pulley effective radius.

  That is, as shown in FIG. 4B, when the pin piece 4 comes into contact with the sheave wall surface at an intermediate effective radius, the pin piece 4 is effective in accordance with the normal direction (O-N) of the pulley. The tangent line T of the radius (pitch line) PL and the contact straight line G ′ coincide with each other. In this state, it contacts with the sheave wall surface at the center portion e in the front-rear direction of the pin piece 4. When the pulley effective radius is a small diameter, as shown in FIG. 4A, the pin piece 4 is in a backward inclined posture in which the upper portion is inclined backward with respect to the normal direction (ON) of the pulley. . In this state, the contact straight line G ′ is tilted forward with respect to the pitch line PL and comes into contact with the sheave wall surface at the rear side portion f of the pin piece 4 in the front-rear direction. When the pulley effective radius is large, as shown in FIG. 4 (C), the pin piece 4 assumes a forward leaning posture in which the upper portion is inclined forward with respect to the pulley normal direction (ON). . In this state, the contact straight line G ′ is inclined forward and downward with respect to the pitch line PL, and comes into contact with the sheave wall surface at the front-rear direction front portion c of the pin piece 4.

  The contact straight line G ′ that is closest to the sheave wall surface 11 of the circular arc surface R can be changed in the vertical direction by arbitrarily setting the position of the center straight line G. A plurality of pin pieces having different end face shapes, for example, two kinds of pin pieces 4 are prepared, and the pin pieces 4 having different end face shapes are used as alternate joint pins of the links L1 and L2, and the position of the pin piece 4 contacting the pulley It is possible to change the periodic noise to white noise by alternately changing.

  In this case, the end face shape 4a of the pin piece is in a normal setting as shown in FIG. 5A because the center straight line G is a cylindrical shape extending in the front-rear direction as shown in FIG. Thus, the contact straight line Gu ′ of the pin piece contacting at the upper position and the contact straight line Gd ′ of the pin piece contacting at the lower position are parallel. As shown in FIG. 5C, when the effective pulley radius is at the intermediate position, the upper contact straight line Gu 'and the lower contact straight line Gd' are both positioned in the tangential direction in a parallel state. Accordingly, the upper contact pin (Gu ′) and the lower contact pin (Gd ′) alternately arranged in the front-rear direction are in contact with the sheave wall surface at positions that are alternately deviated by a predetermined distance d in the vertical direction. When the pulley effective radius is small, as shown in FIG. 5 (B), the upper contact straight line Gu ′ and the lower contact straight line Gd ′ are parallel and both have a front rising slope, and the rear portion is shifted by the same predetermined distance d. When the effective radius of the pulley is large and the effective radius of the pulley is large, as shown in FIG. 5D, the upper contact straight line Gd ′ is parallel and has both forward and downward slopes, and after the same predetermined interval d is deviated. Touch the sheave wall at the side.

  That is, when the end face shape of the pin piece is set to the normal setting, the contact position deviation d is constant regardless of the difference in the pulley effective radius. Accordingly, similarly to the pin length random described in [Problems to be Solved by the Invention], the pin contact position deviation amount d = 0.14 mm is set, and other conditions are the same as the pin length random. As shown in FIG. 6, the pitch is different with respect to the pin sandwiching pulley radius.

Here, the calculation of the random top and bottom of the pin contact position is as follows with reference to FIG. When the endless belt having the pitch l is sandwiched between the radius R positions of the pulleys, the pin contact position is deviated by d from the upper contact pin Pu following the lower contact pin Pd.
l ′ = (l ² + d ² ) ^1/2
l ′ = 2Rsin (γ / 2)
It becomes. Therefore,
γ = ² sin ⁻¹ [(l ² + d ² ) ^1/2 / 2R]
Also,
α = tan ⁻¹ (d / l)
From the above,
θ ′ = (γ / 2) + α, θ ″ = (γ / 2) −α
Is required.

Furthermore, thinking like the previous pin length random (for details, see Japanese Patent Application No. 2004-173267),
In case of top contact-bottom contact-top contact,
Virtual pitch = 2Rsin θ ′
Bottom contact-top contact-bottom contact
Virtual pitch = 2Rsinθ ”
It becomes.

  Therefore, in the case of the upper and lower random by the upper contact pin and the lower contact pin described above, an endless belt can be obtained in which the vibrations having the frequency composed of the phase difference cancel each other out at a predetermined position of the pulley effective radius. However, the range is extremely limited, and it is impossible to obtain a frequency composed of the ideal phase difference over a wide range of the pulley effective radius.

  In the present invention, the center line G (see FIG. 3) of the arcuate surface R of the pin end face shape is inclined in the front-rear direction, that is, the center line G shown in FIG. 3 is perpendicular to the vertical line LL. On the other hand, the tilt angle is set at a predetermined angle with respect to the vertical direction line.

  The contact pin piece 4 of the joint pin adjacent to the belt in the front-rear direction has two types of different shapes on both end faces, and both end faces of one pin piece (upper contact pin) are arcuate as shown in FIG. The contact straight line Gu ′ that is parallel to the front-rear direction center line G of the surface R and closest to the sheave wall surface has a shape that is inclined forward and downward with respect to the front-rear direction (the direction perpendicular to the up-down direction line LL). Both end surfaces of the other pin piece (upper contact pin) have a shape in which the contact straight line Gd 'of the similar arc surface R is inclined upward in the vertical direction.

  When these pin pieces (the upper contact pin and the lower contact pin) contact at an intermediate position of the pulley effective radius, as shown in FIG. 8C, the upper contact pin and the lower contact pin also have the pulley radius line (O -N) The sheave wall surface is contacted at the center position in the front-rear direction of the upper pin, and the mutual shift amount is d. When the pin piece 4 contacts at a small diameter position of the pulley effective radius (underdrive), as shown in FIG. 8B, each pin piece is on the rear side with respect to the pulley radius line ON. The upper contact pin (Gu ′) and the lower contact pin (Gd ′) are also in contact with the sheave wall surface on the rear side of the pulley radius line (O-N). In this state, the contact position of the upper contact pin (Gu ′) and the contact position of the lower contact pin (Gd ′) are at positions (deviation amounts) dud that are separated from each other as compared with the intermediate position (d). (Dud> d). When the pin pieces 4 come into contact with each other at a position where the pulley effective radius is large (overdrive), as shown in FIG. 8D, each pin piece has its upper part on the front side with respect to the pulley radius line (ON). Therefore, both the upper contact pin (Gu ′) and the lower contact pin (Gd ′) are in contact with the sheave wall surface on the front side of the pulley radial line (ON). In this state, the contact position of the upper contact pin (Gu ′) and the contact position of the lower contact pin (Gd ′) are at positions (deviation amounts) dod that are closer to each other than the intermediate position (d). (D> dod).

  Thus, the smaller the pulley effective radius, the greater the contact position (deviation amount) of the sheave wall surface between the upper contact pin and the lower contact pin (dod <d <dud), and the larger the deviation amount, the more random amount (random pitch). Difference) increases. On the other hand, as shown in FIG. 6, the vertical random amount (virtual pitch difference) due to the pin contact position increases as the pulley effective radius decreases, and the random amount change due to the pin end surface shape and the pin contact position vertical random The change due to the characteristic is a direction that cancels out the pulley effective radius, and the change in the random amount due to the gear ratio is reduced.

  Note that the relationship between the contact straight line Gu ′ of the upper contact pin and the contact straight line Gd ′ of the lower contact pin described above is a direction that approaches a relatively small pulley effective radius side and separates on a large pulley effective radius side. Any gradient may be used. For example, as shown in FIGS. 9 (A), (B), (C), (D), various types are possible.

  When the pin contact position deviation amount is set so as to correspond to the pulley effective radius in the same condition as the pin length random shown in FIG. As shown in FIG. 10 (B), the difference between the pitch at the time of upper contact-lower contact-upper contact and the pitch of lower contact-upper contact-lower contact (random pitch) is It becomes almost constant.

  Next, a partially modified embodiment will be described with reference to FIGS. In the embodiment described above, the pin end surface shape is based on the random top and bottom of the pin contact position using two types of pin pieces of the upper contact and the lower contact, but in this embodiment, the pin lengths are alternately different. Based on random pin length.

  In the pin length random using two types of contact pin pieces, long (long) and short (short), the end face shape of the pin piece 4 is centered on the center line G extending in the front-rear direction as shown in FIG. In the case of forming a cylindrical shape with the circular arc surface R in the vertical direction, as shown in FIG. 11A, in the case of normal setting, both the long pin and the short pin have the same end surface where the contact straight lines Gl ′ and Gs ′ are the same. Set to shape. In this case, as shown in FIGS. 11B, 11C, and 11D, both the long pin and the short pin have the same contact position with the sheave wall surface regardless of the difference in the pulley effective radius. That is, when contacting the intermediate position of the pulley effective radius (C), both the long pin and the short pin are at the central position, and when the pulley effective radius is contacting at the small diameter position (B), both pins are the same on the rear side. When the pulley contacts at the position and the pulley effective radius is at the large diameter position (D), both pins contact at the same position on the front side.

  In the embodiment of the present invention, the end faces of the long pin and the short pin are different in the gradient of the contact straight lines Gl ′ and Gs ′. Specifically, as shown in FIG. 12A, both end surfaces of each pin piece 4 are such that the contact line Gs ′ of the short pin is inclined forward with respect to the contact line Gl ′ of the long pin. Form a shape. Accordingly, as shown in FIG. 12C, when each pin piece 4 comes into contact with the intermediate position of the pulley effective radius, the long pin (Gl ′) and the short pin (Gs ′) are in the same position at the sheave wall surface. In contact with the sheave wall surface alternately with a virtual pitch difference (random pitch difference) based on the difference in length between both pins.

  And when each pin piece 4 contacts in the small diameter position of a pulley effective radius, as shown in FIG.12 (B), both pins are back-tilt whose upper part becomes a back side with respect to the pulley radius line ON. Both the long pin and the short pin come into contact with the sheave wall at the rear end. However, as described above, since the slopes of the contact straight lines Gl ′ and Gs ′ of both pins are different, the contact position g of the long pin is the contact position of the short pin. Lower side than h. When each pin piece 4 contacts at a position where the pulley effective radius is large, as shown in FIG. 12D, both pins are before the upper part is inclined forward with respect to the pulley radius line ON. The long pin (Gl ′) and the short pin (Gs ′) are both in contact with the sheave wall surface on the front side, but the contact position i of the long pin is on the upper side with respect to the contact position j of the short pin. .

  Thereby, due to the difference in pulley effective radius, the contact position of the long pin and the short pin with respect to the sheave wall surface changes, and in the direction of increasing the random amount when the pulley effective radius is small, as in the case of the above-described randomness of the pin contact position, When the pulley effective radius is large, the random amount is changed in a decreasing direction. This is the direction to cancel the change in the random amount (random pitch difference) due to the change in the gear ratio of the pin length random shown in FIG. 14, and the change in the pulley effective radius is the same as that shown in FIG. 10B. Regardless of this, the difference (random amount) in the virtual pitch is substantially constant. This makes it possible to maintain the period in which the long pin and the short pin are in contact with the sheave wall surface at the same phase in which the vibrations cancel each other out of phase, regardless of changes in the pulley effective radius.

  Even if the pin length is random, the short pin contact straight line Gs ′ may be inclined forward relative to the long pin contact straight line Gl ′. For example, FIGS. 13 (A), 13 (B), ( Various types of C) and (D) are conceivable, and further, both contact straight lines Gl ′ and Gs ′ do not necessarily intersect within the pin end surface.

  In the above-described embodiment, the joint pin 3 is configured by a pair of pin pieces that are in rolling contact with each other, and only one of the pair of pin pieces is described as an endless belt that contacts the sheave wall surface. The belt may not be of this type. For example, the joint pin is constituted by one pin, and one link plate of the first and second links is non-rotatably connected to the pin, and the link of the other link A plate may be rotatably connected to the pin, and the shape of both ends of the single pin may be the same as the contact pin piece described above, and a block is interposed between a pair of joint pins. The contact end surface shape of the block and the pin may be set as described above by applying to an endless belt configured to contact the sheave wall surface (see, for example, Japanese Patent Application Laid-Open No. 2002-174302). . In addition, the end face shape of the pin may be changed to a curved line curved in the vertical direction or a combination of straight lines or curved lines so as to be convex in the vertical direction instead of the circular arc curved in the vertical direction as described above. it can. It is also conceivable that the end face shape of the pin is formed by a circular arc surface that curves in the front-rear direction, and the pitch of the pins adjacent in the front-rear direction is changed.

The side view which shows the endless belt for transmission which can apply this invention. The plan view. It is a figure which shows the pin (piece) of the said endless belt for transmission, (A) is a front view of the pin in the state which contacted the sheave wall surface of a pulley, (B) is a top view, (C) is a side view. . It is a side view of the said pin, (A) is the state which contacted the small diameter position of the pulley effective radius, (B) is the state which contacted the intermediate position of the pulley effective radius, (C) is the large pulley effective radius. Each state in contact with the radial position is shown. It is a figure which shows the pin contact position up-and-down random where the pin end face shape consists of two kinds of pins of the upper contact position and the lower contact position, and (A) shows a normal setting in which the upper contact straight line and the lower contact straight line are parallel. , (B) shows a state in contact with the small diameter position of the pulley effective radius, (C) shows a state in contact with the intermediate position, and (D) shows a state in contact with the large diameter position. The figure which shows the relationship between a pulley effective radius and a virtual pitch in the pin contact position up-and-down random by the said normal setting. The figure which shows a contact state with the sheave wall surface in the said pin contact position random top and bottom. (A) shows an embodiment of the present invention that is applied randomly above and below the pin contact position, (B) is in contact with the small diameter position of the pulley effective radius, and (C) is in contact with the intermediate position. (D) is a figure which respectively shows the state which contacted the large diameter position. It is a figure which shows other embodiment of this invention which concerns on the said pin contact position up-and-down random, (A)-(D) shows a respectively different representative example. (A) shows the vertical displacement amount of the preferred pin contact position corresponding to the pulley effective radius in a predetermined endless belt, and (B) shows the vertical contact position random corresponding to the pulley effective radius. (A) shows a contact straight line in which the pin end surface shape is a circular arc surface in the vertical direction in the pin length random with two types of pin lengths, and (B) is in contact with the small diameter position of the pulley effective radius. A state, (C) is the state which contacted the middle position, (D) is a figure which shows the state which contacted the large diameter, respectively. (A) shows an embodiment of the present invention applied at random to the pin length, (B) is in contact with the small diameter position of the pulley effective radius, and (C) is in contact with the intermediate position. (D) is a figure which shows the state which contacted the large diameter position, respectively. It is a figure which shows other embodiment of this invention which concerns on the said pin length random, (A)-(D) show a respectively different representative example. The figure which shows the relationship between the pulley effective radius which concerns on pin length random, and a virtual pitch.

Explanation of symbols

1 Endless belt for transmission 2 Link plate 3 Joint pin 4 Pin piece (pin)
4a End surface 4b, 5b Rolling surface 5 Pin piece 10 Primary or secondary pulley 11 Sheave wall surface 12 Fixed sheave 13 Movable sheave Gu ′ Upper contact pin contact straight line Gd ′ Lower contact pin contact straight line Gl ′ Long pin contact straight line Gs ′ Short pin Contact straight line

Claims (5)

A plurality of link plates are connected to each other by joint pins made up of a pair of pin pieces having rolling surfaces that abut against each other , and one end of the pair of pin pieces is a sheave wall surface of the pulley. In the endless belt for transmission, which constitutes an engaging means that can transmit torque in contact with
Pin pieces constituting said engagement means has two different Do that the timing of contacting the sieve wall, the two pins pieces, at least two random pitch by contacting sequentially the sieve wall Configure
Both end surfaces of the two types of pin pieces have arc surfaces that curve in the vertical direction of the belt, and a contact straight line closest to the sheave wall surface of the arc surface is on one of the two types of pin pieces. On the other hand, the other pin piece is arranged in the lower part,
The contact line of the one pin piece is inclined so as to face downward in the forward direction relative to the contact line of the other pin piece,
Wherein the end faces of the two pins pieces, so as to cancel the difference of the random pitch changes corresponding to the pulley effective radius about the position in contact with the sheave wall, corresponding to the previous SL pulley effective radius Shi Formed so that the contact position with the wall surface of the groove is relatively changed,
Endless belt for transmission. A plurality of link plates are connected to each other by joint pins made up of a pair of pin pieces having rolling surfaces that abut against each other , and one end of the pair of pin pieces is a sheave wall surface of the pulley. In the endless belt for transmission, which constitutes an engaging means that can transmit torque in contact with
Pin pieces constituting said engagement means has two different Do that the timing of contacting the sieve wall, the two pins pieces, at least two random pitch by contacting sequentially the sieve wall Configure
Both end surfaces of the two types of pin pieces have arc surfaces that are curved in the vertical direction of the belt, and one of the two types of pin pieces is a long pin longer than the other and the other is a short pin shorter than the other. And
The contact straight line closest to the sheave wall surface of the arc surface is inclined such that the short pin is downward in the forward direction relative to the long pin,
The two end faces of the types of pin pieces, wherein so as to cancel the difference between the random pitch, the corresponding prior Symbol pulley effective radius sheaves which varies in response to the pulley effective radius about the position in contact with the sheave wall It is formed so that the contact position with the wall surface is relatively changed.
Endless belt for transmission. The two types of pin pieces that constitute the engaging means include a first group of pin pieces that generate a constant period of vibration by contact with the sheave wall surface, and a phase of the same period to cancel the constant period of vibration. A mixture of the second group of pin pieces that generate a shifted vibration,
The power transmission endless belt according to claim 1 or 2 . Pin pieces constituting said engaging means comprises a pin piece of the pin strip of the belt travel direction rear side of the pair,
The transmission endless belt according to any one of claims 1 to 3 . A primary pulley having a movable sheave and a fixed sheave each having a sheave wall surface capable of contacting the endless belt for transmission;
A secondary pulley having a movable sheave and a fixed sheave each having a sheave wall surface that can contact the endless belt for transmission;
The transmission endless belt according to any one of claims 1 to 4 , wound around the primary pulley and the secondary pulley,
By moving the movable sheave closer to or away from the fixed sheave, the pulley effective radius of the primary pulley and the secondary pulley is changed,
Belt type continuously variable transmission.

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