JPS6225935Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable speed pulley for driving an engine auxiliary machine, particularly to a variable speed pulley equipped with a planetary gear mechanism.

As a variable speed pulley for driving engine auxiliary equipment, for example, the type shown in FIG. 1 has already been proposed (Utility Model Application No. 117384/1986). In the figure, reference numeral 1 denotes an input shaft integrally connected to a crankshaft 2 of an engine by a bolt 3, and a carrier 5 of a planetary gear mechanism 4 is integrally provided to this input shaft 1. A plurality of planetary gears 6 are rotatably supported on the carrier 5 via bearings 8 on drive pins 7 press-fitted into the carrier 5 at circumferentially spaced positions.
A ring gear 9 that meshes with the planetary gear 6 is integrally connected to an output pulley 10, which is an output member, by a screw 11.
It is supported by the input shaft 12 via a V-belt (not shown), and is drivingly connected to a water pump and an alternator via a V-belt (not shown). A sun gear 13 that meshes with the planetary gear 6 is integrally connected to a brake drum 14 of the brake device by a screw 15, and the sun gear 13 is supported on the input shaft 1 via a bearing 16, and a one-way clutch 17 is connected between the sun gear 13 and the input shaft 1. is inserted. With this configuration, when the brake band 18 is tightened around the outer periphery of the brake drum 14, the sun gear 13 integrated with the brake drum 14 becomes fixed, and the speed is increased compared to the input to the ring gear 9 based on the planetary gear principle. The rotation is output and transmitted to the output pulley 10, and on the other hand,
When the brake band 18 is loosened and the brake is released, the one-way clutch 17 inserted between the sun gear 13 and the input shaft 1 causes the sun gear 13, carrier 5, planetary gear 6, and ring gear 9 to rotate together. , the rotation of the crankshaft is directly transmitted from the input shaft 1 to the output pulley 10 at a speed ratio of 1:1.

Reference numeral 20 denotes a lubricant holding cover that covers the open side of the planetary gear mechanism 4. Its outer edge 20a is fitted onto the outer periphery of the ring gear support portion of the ring gear 9 and the output pulley 10, and the lubricant holding cover is secured by the screw 11 described above. 20 is fastened together with the ring gear 9 to the ring gear mounting portion, and is integrally connected to the brake drum 14 by screws 15.
3 and the inner edge 20 of the lubricant holding cover 20
An oil seal 21 is press-fitted and fixed between the b and b to provide a slidable seal, thereby preventing grease, etc., filled in the gear meshing portions of the planetary gear 6, ring gear 9, and sun gear 13 of the planetary gear mechanism 3. The lubricant is sealed by a holding cover 20 to prevent it from flowing out and scattering from the gear meshing part. As shown in FIG. 2, the brake band 18 has one end 18a fixed to the vehicle body, and the other end 18a.
b is connected to a negative pressure actuator 24 via a connecting member 22 and a wire 23 so as to be actuated. A tension spring 25 is connected to the connecting member 22, and the brake band 18 is normally connected to the brake drum 1.
4 is energized so as not to be fixed.

The negative pressure actuator 24 has a housing 26 that is attached and fixed to the vehicle body, etc. The inside of this housing 26 is divided into two left and right chambers 26a and 26b by a diaphragm 27, and an operating rod 28 is fixed to the diaphragm 27. This rod 28 is slidably supported in the axial direction of the housing 26, and the wire 23 is connected under tension to the outer end of the rod 28. The chamber 26a of the negative pressure actuator 26 is a negative pressure chamber, and is connected to the conduit 29 and the negative pressure solenoid valve 30.
As shown in FIG. Negative pressure is supplied to the negative pressure chamber 26a, the diaphragm 27 is moved to the left, and the brake band 1 is moved to the left.
8 is pulled to fix the brake drum 14.

In order to control the opening and closing of the negative pressure solenoid valve 30, an engine rotation sensor 35 is connected to the negative pressure solenoid valve 30 via a control circuit 34, and when the engine rotation sensor 35 detects a predetermined signal, it outputs a switching control signal. output, negative pressure solenoid valve 3
Solenoid 0 is configured to be energized to open solenoid valve 30 to vacuum source 31 .

The conventional device having the above-mentioned configuration has, for example, a speed change characteristic as shown in FIG. The solenoid valve 30 is energized and opened, negative pressure is supplied from the vacuum source 31 to the negative pressure chamber 26a of the negative pressure actuator 24, and the diaphragm 27 moves to the left end position in FIG. 2 against the spring force of the tension spring 25. Then, the brake band 18, which was previously biased to the release position by the spring force of the tension spring 25, is tightened around the drum 14, braking and fixing the drum 14.

By fixing the brake drum 14, the sun gear 13, which is integral with the drum 14, is also fixed. As a result, the rotation of the input shaft 1 connected to the engine crankshaft 2 is increased by the speed ratio of the rotation ratio = 1 + number of teeth of the sun gear / number of teeth of the ring gear by the ring gear 9 and the output pulley 10 integrated therewith. It is transmitted by However, in a planetary gear mechanism, the number of teeth on the sun gear is always less than the number of teeth on the ring gear, so the speed increasing ratio is smaller than 2 no matter how the number of teeth is selected.

The engine speed then increases to a predetermined value.
When RC is exceeded, the negative pressure solenoid valve 30 is deenergized, the valve body 32 is returned to the position shown in the second figure by the spring 33, the atmosphere communication port 30b is opened, and atmospheric pressure is supplied to the negative pressure chamber 26a. Under the action of the tension spring 25, the diaphragm 27 is moved, and the brake band 18 releases the brake drum 14, leaving it free. As a result, the brake drum 14 and the sun gear 13 integrated therewith are free to rotate, so rotation is no longer transmitted via the planetary gear mechanism 4, and on the other hand, the one-way clutch 17 acts to reduce the rotation of the input shaft 1 to 1. It is transmitted to the output pulley 10 at a speed ratio of :1. This causes the output pulley to rotate at the same speed as the input shaft 1.

However, in the case of such variable speed pulleys at the tip, the speeds of the input shaft and output pulley depend only on the rotational speed of the engine, and in particular, the speed of the output pulley is increased when the engine speed is low. This not only increases the load on the engine and easily impairs the acceleration performance of the vehicle during sudden acceleration from low engine speeds, but also causes a rapid rise in engine speed during sudden acceleration, resulting in a large shift shock if the gear is changed at this time. The problem of easy handling remained unresolved.

The present invention was developed with a focus on these inconveniences, and uses a throttle opening sensing device installed in the accelerator system to automatically release the negative pressure solenoid valve whenever the throttle opening exceeds a predetermined amount. The purpose of this invention is to solve the above problems by configuring the system so that it can be released.

Hereinafter, the present invention will be explained based on the drawings.

FIG. 4 is a diagram showing an embodiment of the present invention. In the figure, the same structural parts as in FIG. 2 are indicated by the same reference numerals as in FIG. 2, and detailed explanation thereof will be omitted.

In the illustrated example, a normally closed switch 37 is connected between the negative pressure solenoid valve 30 and the control circuit 34 and is operated by a throttle opening sensing device 42 that detects the throttle opening based on the position of the accelerator pedal 36 of the automobile.
(switch circuits) are connected in series. The throttle opening sensing device 42 is connected to the accelerator pedal 3
6, and an arithmetic circuit 41 that calculates the throttle opening based on the signal from the sensor 40 and operates the normally closed switch 37. The pedal 36 is configured to open only when the pedal 36 is depressed by a predetermined amount or more, for example, almost at full throttle.

It goes without saying that the switch circuit 37 may be composed of a relay or a transistor circuit in addition to a mechanical ON-OFF normally closed switch.

Next, the effect will be explained. An example of a speed change pattern of the variable speed pulley based on the embodiment shown in FIG. 4 is shown in FIG.

During normal running, when the engine speed is from idling to a predetermined speed RC, the negative pressure solenoid valve 30 operates and is energized based on the switching control signal from the control circuit 34, and negative pressure is applied from the vacuum source 31 to the negative pressure actuator 24. As a result, the brake band 18 (braking device) tightens the brake drum 14 (braking device), so that the output pulley 10 is accelerated more than the input shaft 1. When the engine speed exceeds a predetermined speed RC, the negative pressure solenoid valve 30 is released to the atmosphere, the brake is released, and the input shaft 1 and output pulley 10 rotate together.

The above operation is the same as before.

Next, when the engine speed is suddenly accelerated from a state lower than the predetermined speed RC with a throttle opening of more than a predetermined amount, the switch 37 is opened, the output from the calculation device 34 is cut off, and the solenoid valve 3
0 is released, the brake band 18 is released, and the output pulley 10 and input shaft 1 are rotated together. That is, it is operated in the pattern shown by the dashed line in FIG.

As mentioned above, when accelerating the engine from a low rotation range (lower speed than RC) with a throttle opening of more than a predetermined amount, the output pulley 10 will no longer be accelerated, so the engine auxiliary equipment driven by it will not increase speed. The negative pressure on the engine is reduced.

As explained above, according to the present invention, when the throttle opening is set to a predetermined amount or more and the vehicle is suddenly accelerated, the output pulley connected to the auxiliary equipment is maintained in a non-acceleration state, so that the rapid acceleration The load on auxiliary equipment placed on the engine is reduced, improving acceleration performance. Further, since the normally closed switch is simply connected in series to the output of the arithmetic unit, effects such as extremely simple and inexpensive construction can be obtained.

[Brief explanation of the drawing]

Fig. 1 is an axial cross-sectional view of the main body of a conventional variable speed pulley, Fig. 2 is a schematic diagram of a conventional control system, Fig. 3 is a characteristic curve diagram showing a shift pattern of a conventional variable speed pulley, and Fig. 4 is a schematic diagram of the control system according to the present invention,
FIG. 5 is a characteristic curve diagram showing the speed change pattern of the pulley according to the present invention. 1...Input shaft, 4...Planetary gear mechanism, 5...Carrier, 6...Planetary gear, 9...Ring gear, 10...Output pulley, 13...Sun gear, 1
4... Brake drum (braking device), 17... One-way clutch, 18... Brake band (braking device), 23... Wire, 24... Negative pressure actuator, 26... Housing, 26a... Negative pressure chamber, 27...Diaphragm, 30...Solenoid valve, 31...Vacuum source, 34...Control circuit, 35...
...Engine rotation sensor, 36...Accelerator pedal, 37...Switch circuit, 40...Throttle opening sensor, 41...Arithmetic circuit, 42...Throttle opening sensing device.

Claims (1)

[Scope of utility model registration request] A carrier rotatably supports a plurality of planetary gears at circumferentially spaced positions, and a sun gear and a ring gear that mesh with the planetary gears, one of the carrier, sun gear, and ring gear is used as an input member, and the input member other than the input member is provided. A braking device is provided in which one of the two is used as an output member and the other is in a free rotation state or a fixed state, and a one-way clutch is inserted between any two of the carrier, sun gear, and ring gear to actuate the braking device. In a variable speed pulley that includes an actuator and a control circuit that outputs a switching control signal using the engine speed as an input signal to the actuator, the control circuit is controlled by a throttle opening sensing device and when the throttle opening is a predetermined amount or more, the control circuit A variable speed pulley, characterized in that the control circuit is provided with a switch circuit for opening the control circuit.