JPH0612137B2 - Chain type steel belt for continuously variable transmission - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a continuously variable transmission having two sets of conical pulleys (hereinafter referred to as pulleys) mounted on two shafts facing each other in parallel and facing each other. The present invention relates to a chain type steel belt that can be wound around.

(Prior Art) There are various types of chain type steel belts that are wound around the above pulley and transmit power, but the basic form thereof is a friction piece for making frictional contact with the above pulley and the friction piece. It consists of a chain to attach the piece. For example, the main form is when a fastening hole is formed in a link plate of a chain and a friction piece is fastened to the hole, and when the chain is held by the friction piece. FIG. 19 shows an example of a conventional chain type steel belt, which is shown by its cross section. Both side surfaces are inclined at a constant angle and the friction pieces are attached so as to hold the chain. In this way, if a friction piece that holds the chain is attached, the contact area with the pulley is large compared to when the friction piece is attached to the attachment hole of the link plate, and it is possible to wrap it stably. However, an opening must be formed in the upper part as a means for attaching to the chain.
Of course, the opening may be closed by a separate member, but the friction piece is deformed by the pressure acting between the friction piece and the pulley and cannot generate a high surface pressure, which causes slippage, resulting in a transmission efficiency. As a result, the transmission power is reduced. Therefore, in order to prevent the friction piece from being deformed by the pressure acting on both side surfaces, it is necessary to increase the plate thickness and increase the bending rigidity, resulting in a heavy friction piece. Further, the increase of the plate thickness does not directly affect the stability of the friction piece when wound around the pulley, and the increase of the weight becomes a serious problem as described above.

(Object of the present invention) The chain type steel belt of the present invention is intended for a belt for fixing a friction piece attached to a link plate of a chain so as to hold the link plate. The above problems remain on the belt. Therefore, the present invention is a technique developed for the purpose of solving these problems, in which the friction piece is firmly fixed to the chain and the friction piece is made as thin as possible to reduce the weight and the chain pitch. To improve the power transmission efficiency by increasing the number of friction pieces mounted per unit length, and further simplifying the means for fastening the friction pieces to the chain to reduce the man-hours for assembling the steel belt. It is intended to provide a belt designed.

(Structure of the present invention) The chain type steel belt according to the present invention has the following features in order to solve the above problems.
That is, the steel belt is composed of a chain and a friction piece, and is a pin link chain or a bushed type chain which has been conventionally used as the chain. A notch groove is formed in the center of the upper and lower sides of the link plate that constitutes the chain. On the other hand, the friction piece has a trapezoidal shape in which both side surfaces are inclined at a certain angle so as to make frictional contact with the pulley, and has a cutout hole in the center, and the cutout hole is closed. However, it does not have an opening and has a quadrangle, generally a rectangle, and grooves are formed on the upper and lower sides of the cutout hole. The size of the cutout hole is such that the vertical side is the distance between the bottoms of the cutout grooves formed on the upper and lower sides of the link plate, and the horizontal side corresponds to the chain width when assembled. Further, the grooves formed on the upper and lower sides of the cutout hole have a groove width slightly larger than the thickness of the link plate and a groove bottom distance slightly wider than the width of the link plate. By the way, a predetermined number of link plates are inserted into the cutout holes through the grooves and are arranged left and right through the cutout grooves to form link plate blocks, and the inner and outer link plate blocks are alternately connected via pins. The steel belt is constituted by being processed.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

(Embodiment) The present invention is a thin steel plate attached to the center of each pitch of the link plate of the chain, to two sets of conical pulleys (Fig. 1) attached to two shafts facing each other in parallel and facing each other. Of the present invention having a trapezoidal friction piece made of steel (Fig. 4,
(See Fig. 5) is a chain type steel for a continuously variable transmission in which the contact radius between the belt and the pulley is steplessly changed by putting the pulleys into and out of each other in an endless state. It is a belt.

The belt of the present invention is the known pin link chain 2 shown in FIGS. 2a and 2b, or the bushed type chain shown in FIGS. 3a and 3b, the inner link plates 3, 3 ... of the chain when assembled. . And notch grooves 5a, 5b having a width equal to the plate thickness of a friction piece 8 described later on the upper and lower centerlines of the pitches of the link plates corresponding to the outer link plates 4, 4 ,. Is provided on the inner link plate, and 6a and 6b are provided on the outer link plate (FIG. 6).
On the other hand, in the trapezoidal friction piece made of a thin steel plate, as shown in FIGS. 7 and 8, the above-mentioned cutout groove 5 of the inner and outer link plates is used.
A cutout hole 12 having upper and lower portions of the K portion to be fitted with a, 5b and 6a, 6b is opened in the central portion, and the necessary number of outer link plates in the chain are sequentially inserted and arranged. , Outer link plate block 10 (9th
), The inner link plate block 11 (see FIG. 10,
(Refer to FIG. 11), these are assembled and connected by a pin 7, and the pin head is crimped to form a series of chain type steel belts.

To further detail each part and shape of the present invention,
Inner link plates 3, 3 ... Outer link plates 4, 4 ...
As shown in FIG. 6, the width B of the link plate is 2 with a radius R centered on the pin 7 forming the outer shape of both ends thereof.
Double or more width. Here radius R ≦ 1/2
(Chain pitch dimension-thickness of friction piece). The width dimension of the link plate is set to the above condition because the link plate is provided with the notch grooves 5 and 6 for mounting the friction pieces as shown in FIG.
Preventing the strength of the link plate from decreasing and increasing the width B of the link plate allows the notch groove to be deep enough, further increasing the degree of fastening between the friction piece and the link plate, and enabling high-speed rotation. Moreover, the firm fastening can be maintained even under the use condition due to the fluctuating load. Further, with such a shape and structure, the pitch of the chain can be shortened, the number of friction pieces per unit length is increased, and it is greatly useful for improving the function. According to the present invention, the outermost surfaces of the outer link plates 3 and 4 and the inner surface of the cutout hole 12 of the friction piece are in contact with each other in order to prevent vibration and improve the function. In calculation, the minimum pitch is the dimension of twice the radius R centered on the pin on the end face portion of the outer link plate and the thickness of the friction piece.

In the belt, the friction piece is formed of a single piece of thin steel plate, the notch hole 12 is closed, has no opening, and is extremely strong as compared with the case where the friction piece is a split type. When the friction piece is a split type, it is generally necessary to use pins or bolts for fastening to the chain, so the friction piece becomes thicker and the chain pitch also increases. Compared with the belt, it is inevitably large and also heavy in weight. As described above, in the present invention, since the friction piece 8 is made of a thin steel plate, the chain pitch can be shortened. However, in order to further reduce the chain pitch, the left and right outermost outer links close to the inner link plate friction piece 8 are formed. The shortest pitch can be obtained by thinning or cutting off the F and F portions (see FIG. 12) of the inner link plate friction piece corresponding to where the radii R of both ends of the plate face each other, as shown in FIG. It is possible to shorten the radius to almost twice the radius R, and it is possible to increase the number of friction pieces in a unit length, which is useful for smoother operation and improvement of transmission force.

Next, as shown in FIG. 7, the outer shape of the friction piece 8 has a trapezoidal shape having a contact engagement with a pulley, has inclined surfaces corresponding to the pulley on both sides, and a link plate is inserted in the center thereof. The link plate is made of a thin steel plate having a notch hole 12 having upper and lower sides of the K portion fitted with the notch grooves 5a, 5b or 6a, 6b.

The notch hole 12 has an inner width that matches the outer width of the outer link plates when assembling the chain, and the outer width of the inner link plates, and the height thereof is on the upper and lower sides of the inner and outer link plates. Dimension from bottom to bottom of the provided notch groove (6th
(Refer to the drawing) b), and the groove 9 into which the link plate can be freely inserted is provided at the center (see FIG. 10) of the friction piece where the number of link plates is an even number at the time of assembly (see FIG. 10). Approximately 1 from the center line to the left or right of the friction piece
It is provided at a position displaced by the number of sheets (see FIGS. 7 and 9).
Further, at the time of assembly, when the inner and outer link plates are even, a groove 9 is provided in the center of the friction piece for the inner link plate and one groove inside the outermost plate of the friction piece for the outer link plate.

The distance between the groove bottoms of the groove 9 is set to a dimension Ba which is slightly larger than the width B of the link plate, and the width is slightly wider than the thickness of the link plate.

Generally, in the chain structure, the number of link plates varies depending on the magnitude of the transmission force, but in the present description, the outer link plates are odd numbered and the inner link plates are even numbered.

In the case of a bushed type chain, the number of inner and outer link plates is generally an even number, but in the case of a two-row chain, the number of inner outer link plates may be one and may be an odd number.

Although the inner and outer link plates are arranged at equal intervals in the one shown in the figure, the space between the link plates may be different because of the required strength, the distance between the pair of conical pulleys, or the speed ratio. It is also possible to assemble them at unequal intervals, instead of arranging them at equal intervals.

Next, the groove 9 is a groove provided to facilitate the assembly of the friction piece 8 and the link plate. As described above, when the number of link plates fitted into the friction piece 8 is an even number, the cutout of the friction piece 8 is formed. On the upper and lower center lines of the holes 12, in the case of an odd number of plates, the positions are shifted to the left or right of the center line by the position corresponding to the thickness of one link plate. In the illustration, the position is shifted to the left.

The position of the groove 9 is defined as described above, but the point is that the groove 9 may be provided at a position where the inner and outer link plates do not interfere with each other and the assembling is easy. Further, since the friction piece 8 engages with the conical pulley, a transmission force is always exerted in the traveling direction and a pressing force is exerted in the left and right directions, so that large rigidity, strength and abrasion resistance are required.

The friction piece of the steel belt according to the present invention is not a split type but an integral type, and is manufactured through the steps of press working and cutting from a steel plate, heat treatment (including various coatings), and polishing, so that the above conditions are sufficiently satisfied. Satisfied, especially because the friction piece is one piece and pins and bolts are not used for fastening to the chain, it can be made as thin as possible to the minimum necessary. It can be shortened and reduced in weight, and is extremely robust in terms of strength compared to the split type, and at the fastening part against high speed rotation and fluctuating load,
It has an excellent effect without any instability factors such as loosening. Next, the method of fastening the friction piece 8 and the chain is as follows. In the outer link plate, the outer link plate is inserted into the groove 9 of the cutout hole 12 provided in the outer link plate friction piece.
Notch grooves 6a provided on the upper and lower center lines of the link plate,
6b is matched with the friction piece, fitted outward, and brought into close contact with the inner surface of the cutout hole 12. Similarly, the outermost link plate on the opposite side is fitted to the friction piece so as to be brought into close contact with the inner surface of the cutout hole 12, and thereafter, after the inner link plate is assembled, the thickness of the link plate is adjusted so that they can rotate satisfactorily. The required number of outer link plates are sequentially inserted from the groove 9 at intervals with a slight gap added, and the left and right sides are fitted through the notch grooves to form the outer link plate block 10 (see FIG. 9). Assemble. Similarly for the inner link plate block, the required number of inner link plates are fitted to the friction pieces for the inner link plate, and the inner link plate block 11 (10th
(See FIG. 11). The outer and inner link plate blocks 10 and 11 are connected by a pin 7 and the pin heads are crimped to form a chain type steel belt.

Further, the friction piece 8 can be formed with the length of the inclined portion which is the contact portion with the pulley at both ends thereof being made longer or shorter as necessary, so that the friction piece 8 shown in FIG. This is the case when reduction is attempted. Further, if necessary, it is possible to set only above the horizontal center line connecting the pins of the chain (see FIG. 15) or below the horizontal center line (see FIG. 16). Furthermore, in order to improve the strength of the friction piece 8, its upper and lower surfaces are
As shown in the figure, it is possible to increase the rigidity by making it a curved surface. Also, in order to increase the contact surface pressure with the conical pulley without changing the pressing force, the wall thickness of the end surface of both end inclined parts should be thin as shown in Fig. 17. Alternatively, it is also possible to provide a kerf on the end face as shown in FIG. 18 to serve for cutting the oil film on the contact surface.
Since the present invention has the above-mentioned structure, its advantages have been mentioned in the description, but it has the following excellent features.

(Effect) (1) The friction piece is made of a thin steel plate that is an integral part, so it has much greater strength and weight than the friction piece having a split type or an opening, and the chain pitch can be shortened. Since it can be measured, it is possible to increase the number of friction pieces per unit length, increase the conductive force and smoothly operate at high speed.

(2) The width of the link plate of the chain is twice the radius centered on the pins forming the outer shape of both ends of the link plate,
If the friction piece is attached more than this, it is possible to make the notch groove for wearing the friction piece deep enough when mounting the friction piece, and with proper fitting, even when using a high-speed fluctuating load, it is better than the fastening part. Stable operation is always possible without causing looseness in the friction piece and without causing the problem of breakage of bolts, which is conceivable with the split type friction piece.

(3) Insert the link plate into the groove 9 for assembly provided in the cutout hole of the friction piece, and sequentially fit the link plates left and right through the cutout groove of the link plate to form the outer link plate block 10 and the inner link plate. Assemble block 11 Pin 7
The chain type steel belt of the present invention can be completed by connecting and caulking. It is extremely simple and easy to process and assemble, and it has excellent advantages not only in terms of function but also in production. .

[Brief description of drawings]

Fig. 1 is a mounting view of a steel belt. Fig. 2 is a known pin link chain. Fig. 3 is a known bushed type chain. Fig. 4 is a chain type steel belt of the present invention. Fig. 5 is XX of Fig. 4. Sectional views 6a and 6b are link plates, a is a front view, b is a side view, FIGS. 7 and 8 are front and side views showing friction pieces, and FIG. 9 is an outer link plate block, which is a fourth view. FIG. 10 is a cross-sectional view taken along line YY of FIG.
Sectional view FIG. 11 is a side view of FIG. 10 FIG. 12 is another form of the friction piece FIG. 13 is a sectional view taken along line P-P of FIG. 12, FIG. 14, FIG. 15 and FIG. 16 are friction pieces FIG. 17 and FIG. 18 are side elevational views of friction pieces. FIG. 19 is a cross-sectional view of a conventional steel belt 2 ... Pin link chain 3 ... Inner link plate 4 ... Outer link plate 5, 6 ...... Notch groove 7 ...... Pin 8 ...... Friction piece 9 ...... Groove 10 ...... Outer link plate block 11 ...... Inner link plate block 12 ...... Notch hole

Claims (1)

[Claims] 1. A continuously variable transmission comprising two sets of conical pulleys, which are installed opposite to each other, and which are mounted on a link plate of a chain with friction pieces which make frictional contact with the pulleys at regular intervals. In a chain type steel belt, a closed notched hole that does not open is formed in the center of the friction piece whose outer shape is trapezoidal, and the width is slightly larger than the thickness of the link plate at the upper and lower sides of the notched hole. , Form a groove whose bottom distance is slightly larger than the width of the link plate,
On the other hand, there is a notch groove in the center of the upper and lower sides of the link plate,
A predetermined number of the link plates are inserted into the groove of the cutout hole of the friction piece, the left and right are fitted through the cutout groove to form a link plate block, and the link plate blocks are connected to each other. Chain type steel belt for continuously variable transmission.