JPH0478854B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a continuously variable friction transmission mainly used in an operating system for relatively heavy objects (hereinafter referred to as heavy objects).

BACKGROUND ART A conical surface that is commonly frictionally engaged with one transmission ring kept in a non-rotating state, a concave transmission surface that is frictionally engaged with a transmission wheel on an input shaft, and a conical transmission surface that is frictionally engaged with a transmission wheel on an input shaft; A "ring non-rotating friction continuously variable transmission" in which a plurality of conical rotors with flat transmission surfaces that frictionally engage the transmission wheel are installed on the transmission system from the input shaft to the output shaft; A "ring rotation type frictionless continuously variable transmission" in which the element that frictionally engages with the flat transmission surface is a non-rotating element, and the gear ring is a rotating element to transmit the rotation of the gear ring to the output shaft,
It is described in Japanese Patent Publication No. 57-13221. These types include the point where the output shaft rotational speed is 0 in the shifting range, and the point that gives the maximum value of torque that can be generated is located near the point where the output shaft rotational speed is 0. Because of these favorable properties, it is suitable for use in a variety of applications.

Problems to be Solved by the Invention The friction continuously variable transmission (hereinafter referred to as R-type transmission for simplicity) described in Japanese Patent Publication No. 57-13221 has the above advantages and has a wide range of applications. However, a heavy object operating device constructed using this device can be In order to stop a heavy object that has reached a predetermined position, the electric motor must be turned off and the transmission must act as an irreversible element. This is because during reverse loads, even if the speed change ring has reached the position where the rotation speed of the output shaft should be zero, there is no force on the transmission side to prevent the output shaft from rotating due to the reverse load. As a result, the output shaft continues to rotate at an extremely low speed, causing the heavy object to fall beyond a predetermined position. One object of the present invention is to keep the power on at all times, to accurately reach a predetermined position without relying on the operation of a complicated automatic control system, and to prevent a stopped state at the reached position. The object of the present invention is to provide a frictionless continuously variable transmission that can maintain constant friction.

Another object of the present invention is to provide torque and operability that can be generated in the vicinity of a point where the rotational direction of the output shaft of a friction continuously variable transmission that can change the rotational direction of the output shaft in either positive or negative directions. The point is that it is provided as a high quality product. Specifically, various types of friction continuously variable transmissions that can change the rotational direction of the output shaft in either positive or negative directions are known, but they are only suitable for small load torques. When it is only used and the load torque is large, a suitable one-way rotation type with a large operating force is used, and the output shaft is reversed by reversing the electric motor that drives the transmission. For this reason, there are problems with quickness and smoothness when using a continuously variable friction transmission to move a heavy object in the positive direction and in the negative direction.

Means for Solving the Problems The present invention solves the problem that the slow rotation of the output shaft that occurs after the speed change ring reaches the position where the rotational speed of the output shaft should be 0 is characteristic of reverse loads, and that the motor and speed change Keeping in mind that this does not occur during positive load when heavy objects are operated from the machine side, the R-type transmission will be modified so that both lifting and lowering of heavy objects can be performed under positive load conditions. According to the present invention, "a conical surface that is commonly frictionally engaged with one transmission ring, a concave transmission surface that is frictionally engaged with a transmission wheel on an input shaft, and a transmission surface that is frictionally engaged with a transmission wheel on an input shaft, and a transmission surface on an output shaft. A gear reduction device is interposed between the input shaft and the speed change ring, which has a plurality of conical shapes with flat transmission surfaces that frictionally engage with the vehicle, and which spans the speed change range in both positive and negative directions. It is characterized by

Function The gear reduction device described above constitutes a friction transmission system while imparting planetary motion to the conical rotor. The gear shift range is shifted so that the rotational speed of the output shaft is set to 0 at the midpoint between the positive gear shift range and the negative gear shift range. This is what I did. Note that the gear reduction device interposed between the input shaft and the speed change ring to shift the speed range is described in Japanese Utility Model Publication No. 11045/1973, but the gear reduction device provided in this is not the same as the actual one. It is for a different purpose than that of an invention.

Embodiment FIG. 1 shows an embodiment of the present invention, and FIG. 2 shows a friction transmission system thereof.

In Figure 1, 1 is the input shaft, 2 is the output shaft, and 3 is the input shaft.
is a conical trochanter, and 4 is a speed change ring.

The conical rotor 3 includes a conical surface 5 that frictionally engages with the speed change ring 4, a concave transmission surface 7 that frictionally engages the transmission wheel 6 on the input shaft, and a transmission wheel 8 on the output shaft 2.
A flat transmission surface 9 that frictionally engages is provided.

The gear reduction device according to the present invention, which has a speed change range spanning both positive and negative directions, includes a sun gear 10 on the input shaft 1, an internal gear 12 on the casing 11, a planetary gear 13, a carrier 14, Spline gear 15 on ring 4 and carrier 1
The rotation of the carrier 14 is transmitted to the speed change ring 4.

FIG. 2 shows the speed change ring 4 rotated by the gear reduction device at KN ₁ (K is a constant smaller than 1, N ₁ is the rotation speed of the input shaft = rotation speed of the electric motor that drives the transmission). If dimensions a to f shown in are used, the rotational speed _N2 of the output shaft 2 is expressed by the following equation.

N ₂ =
(e/f+b/d)K-(b/d-a/c)/e/f+
a/cN ₁ ………(1) In addition, R where the speed change ring is kept in a non-rotating state
The rotational speed N _2R of the output shaft of the type transmission is determined by setting K in the above formula to 0, and N _2R = -(b/d-a/c)/e/f+a/cN ₁ ...
…(2).

In these equations, a is a variable whose magnitude changes depending on the position of the speed change ring. For R-type transmissions, where the gear ring is kept non-rotating, the direction of rotation of the output shaft is opposite to the direction of rotation of the input shaft, and N _2R
The absolute value of increases as a increases (as the speed change ring moves away from the apex of the conical surface of the conical trochanter)
the point where the condition of a:b=c:d is satisfied,
That is, it becomes 0 when a:b=c:d. The constant term (e/f+b/d)K added due to the presence of the gear reduction device is such that the numerator of the above equation (1) is a
As the value increases, the value is changed in the process of "positive value → 0 → negative value". Figure 3 shows that N ₁ =
1800RPM, KN ₁ = 335RPM, 400RPM,
It is a drawing illustrating the relationship between the rotation speed of the output shaft and the illustrated dimension 2x/D in the cases of 450 RPM and 500 RPM. x indicates the position of the speed change ring.

When the rotational direction of the output shaft 2 is changed, the only elements that change the rotational direction are the transmission wheel 8 and the pressure contact force generator 17 that rotates integrally with the transmission wheel 8, and the inertial resistance that is applied when the rotational direction is changed is extremely small.

Effects of the Invention The device according to the present invention is suitable for use in a heavy object operating device, and allows operations to be performed smoothly and quickly, as well as being able to accurately stop a heavy object at a desired position. It is intended to do so.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional side view showing an example of a continuously variable friction transmission according to the present invention, FIG. 2 is a drawing showing the transmission system of the transmission shown in FIG. 1, and FIG. 3 is an explanation of the speed change performance of the transmission according to the present invention. FIG. 1... Input shaft, 2... Output shaft, 3... Conical trochanter, 4... Speed change ring, 5... Conical surface, 6... Transmission wheel on input shaft, 7... Concave section transmission Face, 8...
...Transmission wheel on output shaft, 9...Flat transmission surface, 10
... Sun gear, 11 ... Casing, 12 ... Internal gear, 13 ... Planet gear, 14 ... Carrier,
15... Spline gear, 16... Gear on carrier, 17... Pressing force generator.

Claims (1)

[Claims] 1. A conical surface that frictionally engages in common with one speed change ring, a concave transmission surface that frictionally engages the transmission wheel on the input shaft, and a flat transmission surface that frictionally engages the transmission wheel on the output shaft. A continuously variable friction transmission characterized in that a gear reduction device is provided with a plurality of conical rotors having surfaces and is interposed between an input shaft and a speed change ring, and has a speed change range that spans both positive and negative directions. Machine.