JPH0648121Y2 - Auxiliary equipment drive transmission device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an auxiliary machine drive transmission device that transmits a variable drive power to each auxiliary machine of an internal combustion engine.

2. Description of the Related Art As a conventional auxiliary machine drive transmission device of this type, for example, one described in US Pat. No. 3,893,343 is known.

In brief, the drive pulley provided at the front end of the crankshaft of the internal combustion engine is formed of a fixed pulley piece and a movable pulley piece that are divided from the direction perpendicular to the axis. The movable pulley piece is slidably supported in the axial direction of the crankshaft, and is urged toward the fixed pulley piece side by a spring member so as to reduce the effective diameter of the pulley. Further, pressure oil is directly supplied to a hydraulic cylinder formed between the fixed pulley piece and the movable pulley piece from a lubricating oil supply circuit that controls lubrication near the crankshaft.

On the other hand, the driven pulley, to which the driving force is transmitted from the drive pulley via the V-belt, is also formed by a fixed pulley piece and a movable pulley piece that are divided in two from the direction perpendicular to the axis, like the drive pulley. The pulley piece is constantly urged by the spring member so that the effective diameter of the fixed pulley piece side, that is, the pulley is increased.

When the engine is idling, the supply of pressure oil from the lubricating oil supply circuit to the hydraulic cylinder is stopped, so that the movable pulley piece approaches the fixed pulley piece side by the spring member to increase the effective diameter of the pulley while the driven pulley piece is driven. The effective diameter of is reduced and the accessories are rotated efficiently.

At high engine speed, pressure oil is supplied into the hydraulic cylinder, which moves the movable pulley piece away from the fixed pulley piece, reducing the effective diameter of the drive pulley and reducing the effective diameter of the driven pulley. Is increased to prevent over-rotation of auxiliary machinery, and the tension of the V-belt is automatically adjusted.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-mentioned conventional auxiliary machine drive transmission device, since the seal for the hydraulic cylinder is insufficient,
There is a risk that the hydraulic fluid pressure-fed into the hydraulic cylinder will leak to the outside, and in particular, when the pressure of the hydraulic fluid in the hydraulic cylinder becomes high due to the centrifugal force of the pulley, oil leakage easily occurs. For this reason, the effective diameter of the pulley cannot be sufficiently increased during high rotation, and it is not possible to prevent over-rotation of the auxiliary machinery. In addition, the oil leaked to the outside adheres to the vicinity of the V-belt and causes slipping, which results in reliable drive. The transmission effect cannot be obtained.

Means for Solving the Problems The present invention was devised in view of the problems of the above-described conventional device, and in particular, the base portion of the fixed pulley piece has an outer end portion bent toward the movable pulley piece side, Further, the supporting portion of the movable pulley piece has a cylindrical portion that is bent so as to be in sliding contact with the inner peripheral surface of the outer end portion, and between the opposing sliding surfaces of the outer end portion and the cylindrical portion. A plurality of front and rear seal members for sealing the hydraulic chamber are provided, and one end portion is opened between the seal members and the other end portion is provided with a return hole opened in the crankcase of the engine. It is characterized in that it is formed along the inner axial direction of the cylindrical portion.

Effect According to this invention having the above-mentioned configuration, the sealing performance of the hydraulic chamber is improved by the multiple front and rear sealing members, and the leakage of hydraulic oil can be sufficiently prevented.

In addition, since the hydraulic oil that leaks between the seals can be returned to the crankcase by the return holes, it is of course possible to prevent the oil from adhering to the wrapping member, and also to close the front seal member, that is, the side close to the hydraulic chamber. A small amount of hydraulic oil may be allowed to leak from the seal member.

In other words, it becomes unnecessary to strongly press the front seal member between the outer end portion of the base portion and the cylindrical portion of the support portion. As a result, friction due to the seal member is reduced, and the movable pulley piece can be smoothly moved in the axial direction.

Further, since the return hole is formed along the axial direction at a position substantially the same as the position where each seal member is formed, even if centrifugal force is applied to the seal member and the sealing performance deteriorates, the leaked oil will not leak. It can be quickly returned to the crankcase.

First Embodiment Hereinafter, a first embodiment of an auxiliary machine drive transmission device according to the present invention will be described.
A detailed description will be given with reference to FIGS.

In the drawing, 1 is a crankshaft of an internal combustion engine, 2 is a drive pulley provided at a front end portion 1a of the crankshaft 1, 3 is a hydraulic pressure supply circuit, and the drive pulley 2 is provided at a front end edge of the crankshaft 1. A fixed pulley piece 4 fixed by a bolt 7 via a base 6, and an outer peripheral surface 1b of the front end 1a of the crankshaft 1.
In addition, the movable pulley piece 5 is provided slidably in the axial direction of the crankshaft 1 via the support portion 8 and the movable pulley piece 5 is arranged opposite to the fixed pulley piece 4. The fixed pulley piece 4 and the movable pulley piece 5 hold a V-belt 31 as a winding member that transmits power to an auxiliary machine (not shown).

The fixed pulley piece 4 has a base portion 6 that is directly fixed to the inner peripheral side by the bolt 7, and the outer end portion 9 of the base portion 6 is substantially U-shaped inward (to the movable pulley piece 5 side). It is bent and formed.

The movable pulley piece 5 has a front end portion of the crankshaft 1 on the inner peripheral side.
The support portion 8 has a supporting portion 8 slidably contacting the outer peripheral surface 1b of the base member 1a. The outer peripheral surface 10a of the supporting portion 8 is the inner peripheral surface 9 of the outer end portion 9 of the base 6.
A cylindrical portion (10) bent so as to be in sliding contact with a is integrally provided.

A substantially annular hydraulic chamber 11 is formed between the base 6 and the support 8.

Further, between the inner peripheral surface 9a of the outer end portion 9 and the outer peripheral surface 10a of the cylindrical portion 10 facing and slidingly contacting the inner peripheral surface 9a, two ring-shaped seal members are provided at a predetermined distance in the front and rear direction. 12 and 13 are installed. Further, the front seal member 12 near the hydraulic chamber 11 is
The pressure contact force on the inner and outer peripheral surfaces 9a, 10a is set to be relatively low, whereas the rear seal member 13 is set to have a relatively high pressure contact force.

Further, a substantially U-shaped spring retainer 14 is interposed between the fixed pulley piece 4 and the movable pulley piece 5. This spring retainer 14 has a bent end 14
While b penetrates the movable pulley piece 5 from the axial direction and is fixed to the movable pulley piece 5 by welding or the like, the bent other end portion 14a penetrates the fixed pulley piece 4 from the axial direction and is fixed. It is slidable with respect to the pulley piece 4. Further, six spring retainers 14 are provided at equal intervals in the circumferential direction, and the movable pulley pieces are provided between the inner surface of the tip end portion 14a of each retainer 14 and the outer surface of the fixed pulley piece 4. 5
Is attached to the fixed pulley piece 4 side, and a coil spring 15 for increasing the effective diameter of the drive pulley 2 is attached.

Further, the hydraulic pressure supply circuit 3 is independently arranged further downstream from the lubricating oil supply passage 17 of the crankshaft 1 connected to the downstream of the main gallery 16, and one end of the hydraulic supply circuit 3 is connected to the end of the bearing 18. A first oil passage 19 penetrating the crankshaft 1 from the diametrical direction, and formed along the central axis direction of the crankshaft 1,
A second oil passage 20 having one end connected to substantially the center of the first oil passage 19 and the other end connected to the oil chamber 20a on the tip side of the bolt 7, respectively.
The oil chamber 20a and the hydraulic chamber 11 are composed of a third oil passage 22 having a relatively small diameter which communicates with each other through the communication port 21 of the support portion 8.

In the figure, 23 is an oil pump for sending oil to both circuits 17 and 19, and 24 is an oil filter.

Further, the communication port 21 has a third oil passage as shown in FIG.
22 in relation to the open end 22a from the front end 21a to the center 21
It is formed in an acute angle over b, and from the central portion 21b to the rear end portion 21c.
Is formed in a substantially rectangular shape, and the opening area of the opening end 22a of the third oil passage 22 is determined by the unique shape.
Is gradually increased as the fixed pulley piece 4 moves closer to the fixed pulley piece 4 side to prevent an excessive increase in the hydraulic pressure in the hydraulic chamber 11 at the beginning of the movement.

Further, reference numeral 25 in FIG. 1 is a return passage for hydraulic oil having a relatively small diameter formed in the axial direction of the tip end portion of the crankshaft 1. The return passage 25 is supported by one end portion 25a in the radial direction of the crankshaft 1. It communicates with the hydraulic chamber 11 through a through hole 26 provided in the portion 8 and the other end 25b communicates with the inside of the crankcase 27. As shown in FIG. 4, the through hole 26 is formed in an acute angle shape from the rear end portion 26a to the front end portion 26b, and by such a shape, the opening area of the one end portion 25a of the return passage 25 is set to the movable pulley piece 5.
Is gradually reduced with the movement toward the fixed pulley piece 4 side, and in combination with the hydraulic fluid flow control by the communication port 21 described above,
It is designed to prevent an excessive rise within 11.

The reference numeral 28 in FIG. 1 is a return hole formed in the cylindrical portion 10 of the support portion 8 along the axial direction.
a is opened to the outer peripheral surface 10a of the cylindrical portion 10 between the respective seal members 12 and 13, the other end 28b is opened to the inside of the crankcase 27, and the hydraulic oil in the hydraulic chamber 11 leaked from the front seal member 12 Is returned to the crankcase 27 before reaching the rear seal member 13. Since the return hole 28 is formed to have an extremely short radial passage length and is formed at the substantially same height position as the formation position of each of the seal members 12 and 13, a centrifugal force is applied to the seal member 12. Even if the sealing performance is deteriorated, the leaked oil can be quickly returned to the crankcase 27.

Further, reference numeral 29 in the figure denotes a solenoid valve provided at the upstream end of the first oil passage 19, and this solenoid valve 29 is operated by inputting an engine speed signal or a rotation speed signal of an auxiliary machine drive shaft. The duty ratio is controlled by the pulse signal from the control circuit 30 which detects the state. The duty ratio control is relatively simple control because the flow rate is controlled by the unique shape of the communication port 21 and the through hole 26, and when the engine speed is extremely low such as when the engine is idling. As shown in FIG. 5 (A), the output of the pulse signal is stopped and the solenoid valve 29 is closed. In the low rotation range, a signal with a small pulse width (W) is output as shown in FIG. 5 (B). In the high rotation range, a signal having a large pulse width is output in the high rotation range to increase the opening time of the solenoid valve 29.

Although the driven pulley on the driven side is not shown, the movable pulley piece divided from the fixed pulley piece is biased toward the fixed pulley piece side by a spring member such as a coil spring in the same manner as the above-mentioned conventional one, and the effective diameter of the pulley is increased. Is formed.

According to this embodiment having the above-mentioned configuration, since the solenoid valve 29 is closed during the idling operation, the hydraulic oil does not flow into the hydraulic chamber 11, and accordingly, the movable pulley piece 5 has the structure shown in FIG.
As shown by the dotted line, the spring pressure of the coil spring 15 moves to the fixed pulley piece 4 side to increase the effective diameter of the drive pulley 2, while the effective diameter of the driven pulley decreases to rotate the accessories efficiently.

Also, when the engine speed is low (about 1500 rpm to 3500 rpm),
With the above pulse width, the solenoid valve 29 opens and hydraulic oil flows into the hydraulic chamber 11 via the hydraulic pressure supply circuit 3, and the movable pulley piece 5 gradually moves in a direction away from the fixed pulley piece 4 to make the pulley effective. Increase the diameter. Here, since the flow rate of the hydraulic oil is controlled by the communication port 21 at the initial stage of the movement of the movable pulley piece 4,
Sudden movement is suppressed and highly precise variable control of the pulley effective diameter is obtained.

Next, at the time of high engine speed, a large amount of hydraulic oil is supplied into the hydraulic chamber 11 via the solenoid valve 29, the movable pulley piece 5 is sufficiently separated from the fixed pulley piece 4 against the pressure of the spring 15, and the first It is held at the solid line position in the figure. Therefore, the effective diameter of the pulley is minimized, and the effective diameter of the driven pulley is increased accordingly.
Over-rotation of the auxiliary machinery is prevented, and the tension of the V-belt 31 is automatically adjusted. 6 (A) and 6 (B) show the opening / closing control of the solenoid valve 29 and the maximum pulley ratio characteristic with respect to the engine speed.

Further, here, the hydraulic oil in the hydraulic chamber 11 is returned to the crankcase 27 via the return passage 25.
Since the respective diameters of the communication port 21 and the communication port 21 are set to be larger than that of the return passage 25, the pressure in the hydraulic chamber 11 at the time of supplying the hydraulic oil does not decrease more than necessary, and the movable pulley piece 5 moves quickly and quickly. Definitely done.

Further, the double sealing members 12 and 13 not only improve the sealing performance, but also the inner and outer peripheral surfaces of the front sealing member 12.
Since the pressure contact force with respect to 9a, 10a is made relatively low to allow some hydraulic oil leakage from the front side seal member 12, the friction due to the front side seal member 12 decreases and the movable pulley piece 5
You can get smooth movement.

The solenoid valve 29 can be directly attached to the cylinder block, which is advantageous in terms of space.

Effect of the Invention As is clear from the above description, according to the accessory drive transmission device of the present invention, the sealing performance of the hydraulic chamber is further improved by the multiple sealing members, and the leakage of hydraulic oil can be sufficiently prevented.

Moreover, even if the hydraulic oil leaks between the seal members, it can be returned to the inside of the crankcase by the return hole, so that leakage to the outside of the engine can be surely prevented, and the sliding of the front seal member can be surely prevented. It is possible to reduce the pressure contact force against the moving surface. As a result, friction is reduced by the seal member, and smooth movement of the movable pulley piece in the axial direction is obtained.

Furthermore, since the return hole is formed along the axial direction at a position substantially the same as the position where each seal member is formed, the sealing performance of the front seal member deteriorates due to the centrifugal force caused by the rotation of both pulley pieces. However, the leaked oil can be quickly returned to the crankcase.

[Brief description of drawings]

1 is a sectional view of an essential part showing an embodiment of an accessory drive transmission device according to the present invention, FIG. 2 is a view in the direction of arrow A in FIG. 1, and FIG.
FIG. 4 is a view in the direction of arrow B in FIG. 1, FIG. 4 is a view in the direction of arrow C in FIG. 1, and FIGS. 6 (A) and 6 (B) are characteristic diagrams showing the opening / closing operation of the solenoid valve and the maximum pulley ratio with respect to the engine speed in this embodiment. 1 ... Crankshaft, 2 ... Drive pulley, 3 ... Hydraulic supply circuit, 4 ... Fixed pulley piece, 5 ... Movable pulley piece,
6 ... Base part, 8 ... Support part, 9 ... Outer end part, 10 ... Cylindrical part, 11 ... Hydraulic chamber, 12 ... Front seal member, 13 ... Rear seal member, 28 ... Return hole .

Claims (1)

[Scope of utility model registration request] 1. A fixed pulley piece fixed to a front end edge of a crankshaft of an internal combustion engine via a base portion, and an axial direction via a support portion on an outer peripheral surface of the crankshaft front end portion which is arranged so as to face the fixed pulley piece. Of the movable pulley piece slidably supported by the fixed pulley piece and the movable pulley piece, and a wrapping member that transmits power to the auxiliary equipment by being sandwiched between the fixed pulley piece and the movable pulley piece; An auxiliary machine drive transmission device comprising: a hydraulic pressure supply circuit that supplies hydraulic oil into a hydraulic chamber formed between the fixed pulley piece and a support portion to move the movable pulley piece. The outer end portion is bent toward the pulley piece side, and the support portion of the movable pulley piece has a cylindrical portion bent so as to be in sliding contact with the inner peripheral surface of the outer end portion. Between the opposite sliding surfaces of the cylinder and the cylindrical part A heavy seal member is interposed, and one end is opened between the seal members and the other end is opened in the crankcase of the engine, and a return hole is formed in the axial direction of the cylindrical portion of the support portion. An auxiliary machine drive transmission device characterized by being formed along.