JPH0776585B2 - Shift pulley - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement of a speed change pulley capable of suppressing vibration of a sliding pulley that slides on a sleeve.

[Prior art]

It is common to have a structure as shown in FIG. 4 as a structure of a variable diameter variable speed pulley used in a conventional belt transmission. Here, a description will be given of the speed change pulley on the drive side. In the figure, 1 is a rotary shaft, 2 is an O-ring, and 3 is a key. Denoted at 5 is a pulley retaining screw which is screwed into the thread groove 4 of the rotary shaft 1. Reference numeral 10 denotes a speed change pulley, which is a fixed pulley or a fixed wheel 14 composed of a fixed conical plate 13 press-fitted into a fixed sleeve 11 via a key 12, a cylindrical portion 16 having a sliding surface 16a, and a sliding conical plate 17. The sliding pulley or the sliding wheel 18 and the key 20 are basically configured. In the sliding pulley 18, a bearing ring 26 is further attached to the outer periphery of the cylindrical portion 16 via a bearing 25, and via the intervening ring 27, in accordance with the operation of the operating device 7 not shown,
It slides up and down as shown by the arrow in the figure. Since the configuration of the operating device 7 is known, the description thereof will be omitted.

The key structure of this type of speed change pulley has a key groove 11d adapted to the size of the key 20 on a part of the outer peripheral surface of the fixed sleeve 11,
The cylindrical portion 16 of the sliding pulley 18 also has a keyway in the axial direction.
It has a structure with 16b each. There, the sliding pulley 18 slides in the axial direction of the fixed sleeve 11, but rotates together with the fixed sleeve 11. Further, in this type of speed change pulley, the sliding contact surface of the sliding pulley 18 needs to be always slidable with respect to the sliding contact surface of the sleeve 11, so that the fitting between the sliding surfaces 11a and 16a does not occur. , Processed to a loose fit of about 0.1 to 0.05 mm. Moreover, the cylindrical portion 16 of the sliding pulley 18 is shorter than the sleeve 11 and is assembled in a penetrating state.
Therefore, as shown in FIGS. 4 (B) and 4 (C), the sliding pulley 18 is always vibrating with respect to the fixed pulley 14 during the rotating operation.

[Problems of conventional technology]

In such a conventional speed change pulley, there are structural problems and structural problems. Fig. 5 (A), (B)
Both (C) and (C) are partial structural views for explaining this problem.

When the key device is machined on this speed change pulley, it is sufficient if the key groove 11d formed on the fixed sleeve 11 is machined with the axis a accurately. However, in reality, a large amount of deviation occurs, as shown by the broken line. Groove 11d '. The same applies to the key groove 16b formed in the cylindrical portion 16 on the sliding pulley 18 side, and the disorder occurs like the groove 16b '. Further, these two grooves 11d and 16b are also likely to have an error in the processing dimension in the depth direction as well.

In particular, a spring key as shown in U.S. Pat. No. 3,421,783 is often used for the purpose of relaxing the impact applied to the key 20 when the pulley is started. In this case, as shown in FIG. 5 (B), the spring key 20 has an advantage that it absorbs an impact due to a swirl, but on the other hand, it is difficult to improve the accuracy of machining such as an end mill. As shown, both the grooves 11b "and 16b" were difficult to machine to desired dimensions. For this reason, it is indispensable to cut the grooves 11b and 16b in advance to a large size, which causes sliding on the sliding pulley 11b.

Therefore, as a countermeasure against this, the key as shown in Fig. 5 (A)
A method has been adopted in which the length l in the axial direction of 20 is reduced to reduce the influence of machining error and, instead, a plurality of keys are applied.

Therefore, in the conventional transmission pulley 10, the length L of the cylindrical portion 16 shown in FIG. 5 (A) is selected to be short in accordance with the length 1 of the key 20 in combination with the above-mentioned irregularity in the accuracy of machining. Therefore, if there is a slight horizontal disturbance on the contact surface of the speed change belt itself, the sliding pulley 18 can repeat large swings at high speed, as shown in FIGS. 4 (B) and (C). Become.
In particular, when the speed change belt is in contact with the speed change pulley near the maximum diameter, that is, when the belt and the pulley are in contact with each other near the outer edge of the pulley, the amplitude of this vibration becomes significantly large.

As a result, first, the lubricating oil 30 is liable to leak, and the sliding contact surface is apt to be scratched, so that the sliding pulley 18 cannot slide. Further, there is a drawback that the bearing 25 is rapidly deteriorated due to the vibration of the sliding pulley.

[Means for solving problems]

In the present invention, the cylindrical portion integrally formed with the disc wheel is closed by the sealing lid so as to surround and cover the sliding portion of the fixed sleeve, and the step protrusions having different diameters are put out from the sealing lid. Lubricating oil and variable medium are enclosed in a closed step-sealing chamber that is exposed and surrounded by a cylindrical part and a fixed sleeve, and the medium is exposed to the outside without scattering the lubricating oil according to the sliding of the inner cylinder part. It is a speed change pulley that is communicated so as to come in and out between.

[Work]

By utilizing the stepped portion of the fixing sleeve, a key groove and a key with high dimensional accuracy can be arranged in the sliding portion between the cylindrical portion and the fixing sleeve, and further, a key long in the axial direction can be attached. Even if the accuracy of fitting between the fixed sleeve and the cylindrical portion is improved more than before, there is little vibration, and the axial length of the sliding portion can be extended, so that stable sliding operation can be maintained. It will be possible.

In addition, by mixing the lubricating oil and the variable volume volume medium into the step sealing chamber and communicating this variable medium with the outside of the step sealing chamber, the lubricating oil is constantly sprinkled on the sliding portion by centrifugal force during rotation. It

〔Example〕

FIGS. 1 (A), (B) and (C) show a sectional structure of one embodiment of the present invention. FIG. 1 (A) is a longitudinal sectional view of the speed change pulley, and FIG. A) is a cross-sectional view taken along the line BB ', and FIG. 7C is a cross-sectional view taken along the line CC' in FIG.

It should be noted that, of the reference numerals attached to FIG. 1, the same components as those in FIG. 3 are designated by the same reference numerals and the description thereof will be omitted, and the portions of different configurations will be mainly described.

A central hole 37 is formed in a fixed sleeve 11 which is a rotary shaft to which the fixed pulley 14 is fixed via a key 12. The oil 30 is injected, and then the sealing screw 40 is screwed onto the opening edge of the hole 38 for sealing. As the oil quality of this lubricating oil 30, one having a relatively low viscosity is selected,
Further, the amount of oil only needs to be secured such that the oil film diffuses over the entire area of the center holes 37, 38 due to centrifugal force when the sleeve 11 rotates. 41 is an air vent hole formed in the sealing screw 40.

The sliding portion of the fixed sleeve 11, that is, the large diameter portion 35 in this embodiment.
As shown in FIG. 1 (B), three connecting holes 42 connected to the lower end of the large-diameter center hole 37 are arranged at an angle of 120 ° from the center with respect to the lower end of the connecting hole 42. It is open.

The sliding pulley 18 rotating integrally with the fixed sleeve 11 is
It has a cylindrical portion 16 having a length substantially equal to the difference in the thickness of the fixed pulley 14 from the length of the large diameter portion 35, and it is located on the sliding contact surfaces 11a, 16a between the sleeve 11 and the cylindrical portion 16, and both Three key grooves 43 are provided so as to extend over each of the key grooves 43, and each of the key grooves 43 reaches the lower end of the large diameter portion 35 of the sleeve 11 and the cylindrical portion 16.
In addition, a cylindrical key 20 having a property of absorbing a shock at the time of starting is inserted in the key groove 43. An example of the cylindrical key 20 is a spring key, and the details of the spring key are known in U.S. Pat. No. 3,421,783 and will not be described.

At the lower end of the large diameter portion 35 of the sleeve 11, the key 20 is provided with a key groove 43.
The stopper 44 that seals to prevent it from coming out of the
It is fixed by 45, and this stopper fitting 44 is provided with a notch 46 so as not to interrupt the communication with the outside of the connecting hole 42. And the keyway
The cross-section semicircular groove 43a provided on the inner peripheral surface of the cylindrical portion 16 forming half of 43 is longer than the key 20, and the sliding pulley 18 slides on the sleeve 11 only by the long portion. It is like this.

At the lower end of the cylindrical portion 16 of the sliding pulley 18, the speed change pulley 11
A stepped protrusion, that is, in this embodiment, a sealing lid 47 that fits into the small diameter portion 36 is screwed by a screw 49 via a packing 48, whereby a central hole 3 as a lubricating oil chamber is formed.
7 and 38 are sealed, and a step sealing chamber 31 whose volume changes in accordance with the sliding of the sliding pulley 18 is formed at the step portion of the large diameter portion and the step protruding portion, that is, the small diameter portion 36. It 50 is an oil seal provided on the sealing lid 47, and 51 is a small diameter portion 36.
It is a stopper fixed to.

In order to disperse the lubricating oil 30 over the entire sliding surfaces 11a and 16a, the sliding surface 16a of the cylindrical portion 16 is provided with a spiral groove 16c and a ring groove 16d connected to the upper end thereof in addition to the concave groove 43a. There is. Further, the sleeve 11 is provided with a through hole 52 which is continuous with the key groove 43 provided on the outer circumference. Therefore, when the sleeve 11 rotates, as shown in FIG. 1 (A), the oil 30 remaining in the holes 37 and 38 during the stop adheres to the inner wall of the hole 37 due to the centrifugal force, and as a result, Oil is fed into the key groove 43 through the through hole 52 which is not provided.

2 (A), (B) and (C) are explanatory views showing the manufacturing process of the key device in the speed change pulley according to the embodiment of the present invention. That is, FIG. 2 (A) shows the primary processing step. At this stage, first, the semi-circular key grooves 11d are formed in the outer periphery of the fixed sleeve 11 in the axial direction until the free ends thereof are opened. Cutting is done by a mill. On the other hand, also on the inner wall of the cylindrical portion 16 of the sliding pulley 18, three semi-circular keyways 43a are similarly machined by the end mill.

At this time, as already described with reference to FIG. 5 (C), since the accuracy of the outer peripheral curved surface of the bit used in the end mill is not precisely spherical, the sleeve 11 side also has a cylindrical portion 16 The side also has a key groove shape having an uneven cross section as shown by a broken line in FIG. 5 (C), for example. Therefore, in this primary processing step, cutting is performed to be slightly smaller than the outer diameter of the outer peripheral surface 20a of the cylindrical key 20, and preliminary processing for performing highly accurate cutting is performed in the next step.

FIG. 2B shows the secondary processing step and the tertiary processing step. In the secondary processing step, in order to obtain the accuracy of the groove cut in the preceding primary processing step, the fixed sleeve 11 and the pulley cylindrical portion 16 are processed in a fitted state. That is, after the three key grooves on the sleeve side and the cylindrical portion side are combined as a pair and an eye mark is provided between the sleeve and the cylindrical portion, a correction process with a drill or reamer 51 is performed in this step. Drill and reamer 51
Is in the sliding direction, that is, in the direction of the rotation axis of the pulley, and because it is a cylindrical cutting process, it is possible to machine with extremely high precision the inner diameter of the cylindrical space formed by the pair of key grooves 11d and 43a, that is, the inner diameter of the key groove 43 Is. Moreover, since roughing is performed in the preliminary primary processing, the load on the drill or reamer 54 is small, and the shaft core does not escape during cutting, so not only the inner diameter but also the groove It is possible to accurately machine the depth and the parallelism with the rotation axis of the pulley. This means that even if the key 20 is cut by making the axial length of the key groove much longer than the conventional one, the intersection of the axial dimensions can be held within a predetermined range.

Further, in the third processing step, the sliding pulley 18 is slid on the fixed sleeve 11, the spacer device 60 is interposed between the fixed pulley 14 and the sliding pulley 18, and in this state, the second processing is performed again. The same drill or reaming process is applied. That is, in the primary processing step, the pulley cylindrical portion
Of the 16 key grooves 16b, the key groove of the length shown by S in FIG. 2 (B) was still end milled, but the predetermined accuracy is not ensured, so this part is not processed in the third processing step. Is cut with a drill or reamer.

After the three cylindrical spaces are provided between the sliding contact surfaces 11a and 16a as described above, the three keys are inserted into the key groove 43 from the free end side of the large diameter portion 35 as shown in FIG. 2 (B). Is inserted. A spring key is used for this cylindrical key, and the surface portion 20a of the spring key 20 is
Is used, in which a cylindrical surface is subjected to polishing in order to maintain a highly accurate tubular shape and to make the sliding contact operation with the key groove 43a smoother.

FIG. 2 (C) shows the free ends of the sleeve 11 and the pulley cylindrical portion 16 after the completion of the third processing step shown in FIG. 2 (B). After the key 20 is inserted, a stopper 44 is attached as shown in FIGS. 1 (A) and 1 (C). After that, the lubricating oil 30 is enclosed, and after the enclosure, the sealing lid 47 is attached via the screw 49 and the packing 48.

[Other Examples]

Although the above-mentioned embodiment has described the example of the single-opening type transmission pulley having the fixed pulley and the sliding pulley, the present invention can be applied to the case of the double-opening type transmission pulley of the type in which both slide. Further, a person skilled in the art can apply the idea of the present invention to a multiple winding type multiple speed pulley of a belt as disclosed in JP-A-56-164270 proposed by the present applicant. In particular, the structure is not limited to the case where there is a sliding pulley having a cantilever support structure in which one end of the speed change pulley is a free end, and it is clear from the structure of the fixed sleeve 11 of the embodiment of FIG. Both ends may be supported on both sides by a structure supporting both shafts, and it is obvious that those skilled in the art can apply the idea of the lubricating mechanism of the present invention to any shape.

Further, as the method for manufacturing the key structure, in the above-described embodiment, the case where the drill for cutting the tip and the reamer for cutting the side surface are used has been described, but it goes without saying that other similar tools may be used.

Further, in the above-described embodiment (FIGS. 1 and 2), the one applied to the drive-side speed change pulley has been described, but the same can be applied to the driven-side speed change pulley as shown in FIG. That is, in FIG. 3, the sliding pulley 18 is
Similar to those shown in FIGS. 1 and 2, except that a spring 62 stretched between this and a stopper 61 fixed to the fixed sleeve 11 is urged so as to be constantly pressed toward the fixed pulley 14. It is constructed and exerts the same effect.

〔The invention's effect〕

Since the stepped portion is formed on the fixed sleeve of the speed change pulley and the high-precision key can be placed here, it is not necessary to open the mating intersection between the sleeve and the cylindrical portion as in the conventional case, and the sliding portion can be axially moved. Has the advantage that it can be configured longer. This means that the vibration of the sliding pulley with the sleeve is almost completely suppressed and the durability is significantly improved.

The volume of the stepped sealing chamber surrounded by the sleeve and the cylindrical portion changes with the sliding operation of the sliding pulley. Since the variable volume medium is taken in and out, the lubricating oil preliminarily enclosed in the sealed chamber does not rise in internal pressure and flow out to the outside.
Lubricating oil is centrifugally supplied to the sliding portion with rotation, so that stability and durability of sliding operation are guaranteed, and reliability and durability are further increased. In addition, the protruding portion or the small diameter portion improves the sealing property of the sealing lid as much as the durability of the sliding portion is improved, and not only there is no oil leakage, but by utilizing this protruding portion,
The speed change pulley itself is not limited to the cantilever support, but can be applied to a double shaft support structure, so that an oilless transmission can be realized even when applied to a large horsepower transmission mechanism.

[Brief description of drawings]

FIG. 1 (A) is a longitudinal sectional view taken along the line AA of FIG. 1 (C) which is an embodiment of the present invention, and FIGS. 1 (B) and (C) are those of FIG. 1 (A). The cross-sectional views taken along the line BB and the line CC, respectively, and FIGS. 2 (A), (B), and (C) are explanatory views of the processing steps of the embodiment of the present invention, and FIG. FIG. 4 (A) is a cross-sectional view of another embodiment of the present invention, FIG. 4 (A) is a cross-sectional view of a conventional transmission pulley, FIG. 4 (B) and FIG. ) (B) and (C) are explanatory drawings for processing the transmission pulley of FIG. 35 …… Large diameter part of fixed sleeve 11 36 …… Small diameter part, 50 …… Oil seal 37 …… Large diameter center hole, 51 …… Stopper 38 …… Small diameter center hole, 52 …… Through hole 39 …… Sealing Lid, 54 ...... Reamer 40 ...... Sealing screw, 60 ...... Spacer device 41 ...... Air vent hole, 61 ...... Stopper 42 ...... Connection hole 43 ...... Key groove 44 ...... Stopper 45 ...... Screw 46 ...... Notch 47 …… Seal lid 48 …… Packing 49 …… Screw

Claims (11)

[Claims] 1. A transmission pulley having a sliding portion for sliding one or both of the cylindrical portions of the facing disk wheel on a fixed sleeve supporting the disk wheel.
A sealing lid is formed at one end so as to cover the sliding portion of the fixed sleeve, and the fixed sleeve has a step protrusion having a diameter different from that of the sliding portion and is exposed to the outside of the sealing lid.
Lubricating oil and a variable medium are sealed in a stepped sealing chamber in a closed state, the volume of which changes with the sliding of the cylindrical portion, and the medium forms a communication hole with an outdoor medium while preventing the lubricating oil from scattering. A speed change pulley that can be pulled in and out after that. 2. The transmission pulley according to claim 1, wherein the fixed sleeve is formed with the sliding portion in a large diameter portion and the step projection portion in a small diameter portion. 3. The transmission pulley according to claim 1, wherein the variable medium is air, and the variable medium is communicated with the outside air through the communication hole. 4. The speed change pulley according to claim 3, wherein the step sealing chamber formed by the fixed sleeve and the cylindrical portion is formed by liquid oil of the lubricating oil and air. 5. The speed change pulley according to claim 4, wherein the step sealing chamber allows the outside air to flow in and out through the communication hole formed in the sleeve. 6. The fixing sleeve according to claim 1, wherein the fixing sleeve has a central hole forming an oil bath portion, and the oil bath portion penetrates the step sealing chamber through a connecting hole. Speed change pulley. 7. The transmission pulley according to claim 6, wherein said communicating hole has an indoor side tip end portion communicating with said oil bath portion and is arranged at a coaxial position with said fixed sleeve and a rotary shaft core. 8. The transmission pulley according to claim 1, wherein the fixed sleeve has one end as a fitting hole for a drive shaft and the other end as a free end. 9. The transmission pulley according to claim 1, wherein the fixed sleeve supports both bearings at each shaft end. 10. The transmission pulley according to claim 1, wherein the sliding portion has a key mounted from the step protrusion toward the sliding portion. 11. The transmission pulley according to claim 10, wherein the key has a substantially cylindrical outer shape.