JP6976333B2 - A method of manufacturing a crossing member for a drive belt used in a continuously variable transmission. - Google Patents

Description

The present disclosure relates to a method of manufacturing a transverse member defined to be part of a drive belt used in a continuously variable transmission having two pulleys and a drive belt. Such drive belts are generally known and are primarily used to run between two transmission pulleys, each of which forms a variable width V-groove. , Each circumferential portion of the drive belt is held in the V-groove.

Known types of drive belts have a substantially continuous row of transverse members, the transverse members attached to and around the perimeter of the endless carrier. Each such crossing member defines an opening, which is open radially outwards of the drive belt to accommodate and limit each perimeter of the endless carrier, while at the perimeter of the endless carrier. Allows the movement of transverse members along. The endless carrier is formed by a plurality of flat, thin rings that are stacked on top of each other in the radial direction. This typical type of drive belt, also referred to by those of skill in the art as a push belt, is known, for example, in International Publication No. 2015/177372, which is an international patent application.

In the above and below description, the axial, radial and circumferential directions are set with respect to the drive belt when arranged in a circular position. Further, the thickness dimension of the crossing member is set in the circumferential direction of the drive belt, the height dimension of the crossing member is set in the radial direction described above, and the width direction of the crossing member is set in the axial direction described above. Is set to.

A known transverse member has one base portion and two pillar portions extending radially outward from the base portion on each axial side of the base portion. The aforementioned opening accommodating the endless carrier is defined between them by one base portion and two pillar portions. The base portion extends between the pillar portions and forms a support surface that forms the bottom of the opening to support the endless carrier on the radial outer side.

In the row of crossing members of the drive belt, at least a portion of the front body surface of the crossing member abuts on at least a portion of the posterior body surface of the preceding crossing member in the aforementioned row, whereas the crossing member At least a portion of the rear body surface abuts on at least a portion of the front body surface of the subsequent crossing member, respectively. At least one of these anterior and posterior surfaces of the transverse member, eg, the anterior surface, includes an axially extending convex curved surface portion. This curved surface portion divides the front surface into a radial outer surface portion and a radial inner side surface portion oriented at a predetermined angle with respect to each other. The crossing members abutting in the drive belt can tilt with respect to each other, while maintaining contact with each other at and through such curved surfaces, and therefore such curvature. The surface portion is hereinafter referred to as a tilting edge. The tilting edge allows the row of cross members of the drive belt to follow the local curvature of the ring stack brought about by the transmission pulley.

For example, in WO 2013/09784, it is known to those of skill in the art to provide precisely defined contact between transverse members in the aforementioned track portions of the drive belt in order to reduce vibration during operation. There is. In particular, between the tilted edge and the radial outer portion of each pillar portion, a portion of the front surface of the transverse member is at least slightly recessed relative to the radial outer portion of the tilted edge and pillar portion. That is, it is dented to some extent. Thus, in a row of crossing members of a drive belt, at least the aforementioned radial outer portions of the tilting edge and pillar portion serve as a mutual contact region between adjacent crossing members, while such mutual contact is a crossing member. It is avoided at the position of the aforementioned recessed portion of the front surface of the. In other words, the thickness of the transverse member is greater at the position of the contact area described above than at the position of the relatively recessed portion of the front surface. However, in practice, such thickness differences are absolutely small, usually on the order of a minimum of 5 micrometers to 10 micrometers and a maximum of about 100 micrometers.

Typically, the cross member is manufactured or cut from a strip or plate of substrate by a known punching process with a punching device. Known punching devices include a die, a guide plate and a punching punch, of which the punching punch has a contour substantially corresponding to the outer contour of the transverse member to be molded, while the die and the guide plate have a die and a guide plate. It has an inner cavity with a corresponding contour in which the punch punch is housed. In a known punching process, the substrate is sandwiched between the guide plate and the die, and the punch punch is pressed from the side of the guide plate to the side of the die through the substrate, thereby the cross member. Cut out from the substrate. Further, in known punching devices and processes, a corresponding punch or ejector is provided on the side of the substrate opposite the punching punch. This latter assembly of the punching device forms the front and / or rear surfaces of the crossing member by plastically deforming the substrate between them by the respective end faces of the punching punch and ejector while punching the crossing member. And allows for dimensional adjustment. In particular, the aforementioned recessed portion of the front surface is made of a corresponding, relatively raised portion of the end face of the ejector. The portion is pushed into the substrate to displace some amount of the substrate and thus the thickness of the substrate is locally reduced. Of course, the amount of substrate displaced to form the recessed portion described above will eventually reach elsewhere in the substrate. In particular, some amount of such substrate is displaced towards the tilted edge and / or towards the aforementioned radial outer portion of the pillar portion, i.e. towards the aforementioned contact area.

According to the present disclosure, known punching processes relate to the resulting thickness of the cross member, especially with respect to the aforementioned difference in thickness between the contact area and the relatively recessed portion of the anterior surface. , Difficult to control in mass production. For example, the amount of substrate displaced from the relatively recessed portion described above to the contact area must be set accurately to achieve the (locally) expected thickness of the transverse member. Must be. Therefore, regular reworking of the end face of the ejector is required to maintain the dimensional accuracy of the cross member manufactured. The force required by the ejector to achieve the required displacement of the substrate is also quite large, but this force must still be precisely controlled between these strokes within each punching stroke.

According to the present disclosure, known punching processes have room for improvement, at least with respect to the required reduction of ejector force, but potentially with respect to the dimensional accuracy of the cross member made within the ejector. In particular, according to the present disclosure, each crossing member is cut from the substrate in at least three steps.
-First, at the position where the above-mentioned relatively recessed portion is provided in the pillar portion later, a crossing member is formed by drilling a hole in the base material with a drilling punch on at least one side of both pillar portions. Cut off at least part of the pillar part of
-Then, by locally compressing the substrate between the two forming tools, a relatively recessed portion is formed in the pillar portion.
-Cut out a portion or all of the contour of the transverse member from the substrate using at least a punching punch and ejector.

According to the present disclosure, since the holes are preformed on at least one side of each pillar portion, the aforementioned amount of substrate displaced to form the recessed portion of each pillar portion will be. It is possible to flow more easily, especially into the free space provided by the holes, at least partially. Therefore, the required ejector force described above is reduced and / or the dimensional accuracy of the cross member is improved.

Preferably, the same tool is used in the second step and the third step, that is, preferably one of the forming tools in the second step also functions as a punching punch in the third step. The other forming tool in the second step also functions as an ejector in the third step. Moreover, in particular, the above-mentioned second step and third step are performed in a short sequence or at least partially simultaneously.

Preferably, in the first step, the holes are drilled in the substrate on both sides of the pillar portion. In this case, four perforated punches are used to form the four holes, preferably allowing the aforementioned amount of substrate to be displaced to both sides of the pillar portion.

Next, the method for manufacturing the above-mentioned crossing member will be described in detail with reference to the following description with reference to the drawings.

FIG. 6 is a simplified schematic side view of a transmission with two pulleys and one drive belt. A known drive belt having a substantially V-shaped cross member is shown in a cross-sectional view of the drive belt facing the circumferential direction of the drive belt, and a separate side view of only the cross member of the drive belt is also included. The vertical sectional view of the punching area of the punching apparatus and the base material arranged in the punching area is schematically shown. The basic process of punching a transverse member is schematically shown together with the punching device of FIG. A novel method of manufacturing a transverse member in three steps is schematically shown. A novel method of manufacturing a transverse member in three steps is schematically shown.

FIG. 1 schematically shows a main part of a continuously variable transmission 100 for use in a power transmission path of a passenger car, for example, in a side view. The transmission 100 is widely known in itself and has at least a first variable diameter pulley 101 and a second variable diameter pulley 102. In the power transmission path, the first pulley 101 is connected to and driven by the prime mover, the engine, and the second pulley 102 is usually connected to the driven wheels of the vehicle via a plurality of gears. ing.

Both transmission pulleys 101, 102 are axially displaceable with respect to the first conical pulley sheave fixed to the pulley shafts 103, 104 of the pulleys 101, 102, respectively, and the pulley shafts 103, 104, respectively. It has a second conical pulley sheave fixed to the pulley shafts 103, 104 only in the direction of rotation. The drive belt 99 of the transmission is housed between the pulley sheaves of the pulleys 101 and 102, and is wound around the pulleys 101 and 102. As is clear from FIG. 1, the trajectory of the drive belt 99 in the transmission 100 includes two linear partial STs and two curved partial CTs, in which in the curved partial CT the drive belt 99 has two transmissions. It is curved around one of each of the pulleys 101 and 102.

During operation of the transmission, the drive belt 99 is sandwiched between these pulley sheaves by the pulley sheaves of both pulleys 101, 102 and thus provides a rotational connection between these pulley sheaves by friction. To this end, the transmission 100 is provided with electronically controllable, normally hydraulically operated means of movement acting on the movable pulley sheaves of the pulleys 101, 102, respectively (illustrated). It has not been). In addition to exerting a tightening force on the drive belt 99, these moving means provide the radial positions R1 and R2 of the drive belt 99 on the pulleys 101 and 102, and thus the pulley shafts 103 and 104 of the pulleys 101 and 102. Also controls the speed ratio provided by the transmission 100 between.

The known drive belt 99 includes an endless carrier 8 and a plurality of crossing members 1. The cross member 1 is attached to the endless carrier 8 along the circumference of the endless carrier 8 in at least a substantially continuous row. In the drive belt 99, the transverse member 1 is movable along the circumference of the endless carrier 8, which usually consists of a plurality of flexible metal strips, i.e., a thin, flat metal ring. One of the metal strips is laminated so as to surround another, that is, they are overlapped with each other.

FIG. 2 shows the known drive belt 99 in more detail. On the right side of FIG. 2, the drive belt 99 is shown in a cross-sectional view facing the circumferential direction of the belt, and on the left side of FIG. 2, a cross section of only the crossing member 1 is shown.

The known crossing member 1 has a base portion 10 and two pillar portions 11, of which the base portion 10 extends mainly in the axial direction of the drive belt 99, of which the pillar portion 11 extends. Each extends predominantly in the radial direction of the drive belt 99 from the respective axial side of the base portion 10. In its thickness direction, the transverse member 1 extends between the rear surface 2 and the front surface 3 of the transverse member 1, and both the rear surface 2 and the front surface 3 are at least substantially in the circumferential direction of the drive belt 99. It is aimed. Between the pillar portion 11 and the base portion 10 of the transverse member 1, the transverse member defines an opening 5 for accommodating a circumferential portion of the endless carrier 8.

At least one pillar of each crossing member 1 to prevent the crossing member 1 of the known drive belt 99 from being able to separate from the endless carrier 8 of the drive belt 99, especially in the linear portion ST of the drive belt 99. The portion 11 is provided with a hook portion 13 extending axially over a portion of the opening 5. Therefore, in the drive belt 99, the endless carrier 8 is accommodated in the central opening 5 of the crossing member 1 by the hook portion 13 of the crossing member 1 in the radial direction.

Each pillar portion 11 of the crossing member 1 is provided with a protrusion or a stud 6, and the stud 6 substantially protrudes from the front surface 3 in the above-mentioned circumferential direction. In the drive belt 99, the stud 6 is inserted into a recess or pocket 7 provided on the opposite side, i.e., the rear surface 2 of the adjacent transverse member 1, thereby at least relative to the inner circumference of the pocket. Relative motion between adjacent transverse members 1 is restricted to the extent determined by the clearance on the outer circumference of the stud 6.

On the axial side of the crossing member 1, the crossing member 1 is provided with a plurality of contact surfaces 12 for contacting the transmission pulleys 101 and 102 (pulley sheaves). These contact surfaces 12 are oriented at an angle that closely matches the angle formed between the conical pulley sheaves of the transmission pulleys 101 and 102 with respect to each other.

The crossing member 1 is provided with a so-called tilting edge 4 on the front surface 3 of the crossing member 1. The tilting edge 4 extends in the axial direction between the radial outer portion of the transverse member 1 having a substantially constant thickness and the radial inner portion of the transverse member 1 inclined inward in the radial direction. Represents the transition part. Normally, the tilting edge 4 is smoothly curved in a convex shape.

In each pillar portion 11 of the transverse member 1, a portion 14 of the front surface 3 of the transverse member 1 is the radius of the tilting edge 4 and each pillar portion 11 as outlined in an exaggerated manner in FIG. It is recessed with respect to the direction outer portion 15. Therefore, in the row of crossing members 1 in the linear portion ST of the drive belt 99, at least the above-mentioned radial outer portions 15 of the tilting edge 4 and the pillar portion 11 are used as mutual contact regions between adjacent crossing members 1. On the other hand, such mutual contact is avoided at the position of the recessed portion 14 on the front surface 3 of the transverse member 1. When these adjacent transverse members 1 are tilted relative to each other in the curved portion CT of the drive belt 99, these transverse members 1 remain in contact with each other at the tilting edge 4.

The transverse member 1 is usually cut out from the plate-shaped or strip-shaped base material 50 in a punching process by the punching device 60. In FIGS. 3 and 4, the punching device 60 and the base material 50 are schematically shown in a cross-sectional view. The punching device 60 is provided with a punching punch 30, an ejector 40, a guide plate 70, and a die 80. Both the guide plate 70 and the die 80 function to sandwich the substrate 50 between them and accommodate the punching punch 30 and the ejector 40 in the guide spaces 71 and 81 of the guide plate 70 and the die 80, respectively. do. The portion 51 of the base material 50 located between the punching punch 30 and the ejector 40 is defined to be the crossing member 1. Therefore, the punching punch 30 and the ejector 40 have contours substantially corresponding to the outer contours of the transverse member 1.

During punching, the bottom end surface of the punching punch 30, that is, the working surface 31, and the top end surface of the ejector 40, that is, the working surface 41 are pressed against the base material 50 on opposite sides of the base material 50, and the punching punch is punched. The 30 and the ejector 40 are simultaneously moved in the normal direction from the punching punch 30 to the ejector 40 so as to completely penetrate the substrate 50. As a result, the transverse member 1 is cut out from the base material 50 along the edge of the die 80, as shown in FIG. Further, during punching, the front surface 3 of the crossing member 1 including the tilting edge 4 of the crossing member 1 and the stud 6 is press-formed by the working surface 41 of the ejector 40 and provided in the crossing member 1 of the crossing member 1. The rear surface 2 including the pocket 7 is press-molded by the working surface 31 of the punching punch 30. In particular, in order to form the pocket 7, a protrusion (not shown) is provided on the work surface 31 of the punching punch 30.

According to the present disclosure, as shown in FIGS. 5 and 6, cutting of the transverse member 1 from the substrate 50 is performed in three steps. In the first step of such a novel manufacturing method shown in FIG. 5, four holes 53 are drilled into the substrate 50 by four drilling punches 90. A portion of the peripheral surface of the perforated punch 90 sets at least one portion of each of the two sides of each of the two pillar portions 11 of the transverse member 1, and the transverse member 1 is also this first step. Should be cut from the substrate 50. In FIG. 5, the material 52 removed from the substrate 50 by the perforation punch 90 and the holes 53 formed thereby are shown by solid lines, while the contour of the transverse member 1 still to be cut. The rest is shown by the dashed line. The hole 53 is aligned with the recessed portion 14 of the transverse member 1, particularly the front surface 3 of the pillar portion 11 of the transverse member 1, which should still be formed.

The same portion of the substrate 50 is then exposed to the second and third steps of the novel manufacturing method shown in FIG. In the second step, the two portions 54 of the substrate 50 located between the preformed holes 53 are two forming tools, i.e. the stamp 100 (only one of which is recognized in the drawing of FIG. 5). It is compressed and plastically deformed between them to form the aforementioned recessed portion 14 of the transverse member 1. As a result of such compression, the substrate 50 compressed between the two stamps 100 gets into it somewhat towards the preformed holes 53. Finally, in the third step, the remnants of the contour of the transverse member 1 are described above in the second process step, preferably as the cutter 30 and ejector 40 of the punching process, respectively, in the conventional punching process described above. The stamp 100 is also used in this third process step to be cut out from the substrate 50.

The present disclosure relates to and includes all features of the appended claims, in addition to the whole of the above description and all the details of the accompanying drawings. The parenthesized reference numerals in the claims do not limit the scope of the claims, but are provided merely as non-binding examples of the respective features. The features described in the claims can optionally be applied separately in any product or any process, but at the same time any combination of two or more of these features can be applied.

The inventions represented by the present disclosure are not limited to embodiments and / or embodiments expressly referred to herein, and are particularly limited to modifications, modifications and practical use thereof to the extent of those skilled in the art. Including application.

Claims (3)

A method for manufacturing a crossing member (1) suitable for use in a drive belt (99) used for a continuously variable transmission.
The cross member (1) has one base portion (10) and two pillar portions (11), the pillar portions (11) substantially parallel to each other from both sides of the base portion (10). Each of the pillar portions (11) is provided with a recessed portion (14) of the front side surface (3) of the crossing member (1), and the recessed portion (14) is provided . The portion (14) is recessed relative to another portion (15) of the front side surface (3), and in the method, the cross member (1) is cut off from the base material (50). In the method of manufacturing the crossing member (1).
The cross member (1) is manufactured from the substrate (50) in at least three process steps.
In the first process step of the three process steps, the holes (53) are drilled into the substrate (50) on at least one side of both pillar portions (11) and the holes (53). Part of the circumferential surface of the three processes represents the side surface of each one pillar portion (11) formed adjacent to the recessed portion (14) of the front surface (3). In the second process step of the steps, the recessed portion (14) is particularly stamped (100) with two stamps (100) located on opposite sides of the substrate (50). Pressing against the substrate (50) by pressing towards each other, the cross member (1 ) comprising the two pillar portions (11) in the third process step of the three process steps. ) By at least the stamp (100) of the second process step, which functions as a punching punch (30) and an ejector (40) in the third process step. A method for manufacturing a crossing member (1), which comprises punching from 50). Perforated before Symbol first process step, on opposite sides of the pillar portion of the both to be formed in the third process step (11), a total of four holes (53), said base (50) The method for manufacturing the cross member (1) according to claim 1, wherein the cross member (1) is manufactured. The pre-Symbol third process step, and executes concurrently with the at least partially the second process step, a method of producing a cross member according to claim 1 or 2 wherein (1).

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