JPS58163854A - Frictional stepless speed change gear - Google Patents

Abstract

PURPOSE:To give wide application of a speed change gear by use of a torque characteristic presented in the proximity of a point at which a revolution speed of an output shaft is zero and irreversibility of said characteristic by providing a maximum speed selection means which changes the stroke end on the high speed side of reciprocal motion of a speed change ring. CONSTITUTION:A link 20 which is pinned to a support fork 16 for a speed change ring 4 and a supporting element which may be shifted in its position are provided so as to give a variety of the stroke end on the high speed side reciprocating stroke given to the speed change ring 4 by a grooved cam 17, (that is the maximum value in revolution of the output shaft 2). The link 20 has a pin 23 which is engaged in a cam groove 22 of the grooved cam 17 and a slot 24 in which the pin 23 on the support element 21 is engaged. The stroke end on the high speed side of the reciprocal motion given to the speed change ring 4 may be changed by setting a mark 25 provided on the support element 25 to a suitable position on a graduation 26.

Description

[Detailed Description of the Invention] Frictionally continuously variable transmissions are used for a wide variety of applications, as it is preferred that the speed change be performed purely mechanically. If a device that provides special effects is developed, the use of continuously variable friction transmissions will be further expanded than currently available.

The present invention forms part of the above development, and includes a speed change ring that is commonly frictionally engaged with a plurality of conical trochanters that perform planetary motion. The object of the present invention is to provide a new friction continuously variable transmission that brings various advantages by taking advantage of the characteristics of the present invention.

In Figure 1, (1) is the input shaft, (2) is the output shaft, (
3) is a plurality of conical rotors that perform planetary motion, and (4) is a speed change ring that is commonly frictionally engaged with these conical rotors.The rotation speed of the output shaft 12) is determined by the speed change ring (4). It is at its highest when it is at the rightmost position, and decreases as the speed change ring (4) is moved to the left until it finally reaches 0.

Figure 2 is a characteristic curve for the device shown in Figure 1 when the rotational speed of the input shaft (1) is constant and the input horsepower is constant, and the rotational speed of the output shaft (2) is the maximum value N From point P to point Q, which is assumed to be a hyperbolic characteristic (NX
T-constant), but when the rotational speed of the output shaft (2) becomes particularly low, it exhibits characteristics different from hyperbolic characteristics. In addition, T
is the torque applied to the output shaft, N is the rotation speed of the output shaft, and 0 is the point at which the rotation speed of the output shaft (2) becomes O. The period from point 8 to point 0 is a region in which the torque T rapidly decreases to point O. The area between the SOOs can be referred to as the torque stalling area. The width W of the torque stall area varies depending on the size of the load, but in most cases, the width W of the torque stall area is
This is about 1/20 of the maximum rotational speed of 1'1max. In this specification, the rotational speed within the width W and the rotational speed close to it are referred to as minute rotational speeds.

In connection with the use of the minute rotational speed, the present invention is provided with a special speed change operating device αQ. This device gives reciprocating motion to the speed change ring (4), and for the stroke ends of the reciprocating motion, the low-speed stroke end is selected at a point that gives a minute rotational speed to the output shaft, and the high-speed stroke end The side stroke end is made variable. Further, the speed change operating device 00) is driven using the output shaft (2) as a drive source through mechanical interlocking means. In the case of the one shown,
Mechanical reduction means include sprocket wheels Ill 02 and their chain days and reduction gearboxes (141
The reciprocating movement of the speed change ring (4) is caused by the shaft (15).
) is guided by the support fork +161, which is guided by the grooved cam (I
71. The grooved cam α is replaceable and is keyed onto the output shaft U81 of the reduction gear box (I41, a9) as shown in Figure 6.
at is a nut for fixing the grooved cam 07).

The maximum value h of the high-speed stroke end of the reciprocating stroke that the grooved cam αη gives to the speed change ring (4) (the riff of the grooved cam 0 as shown in Fig. 4), naX, that is, the maximum rotational speed of the output shaft (2) In order to make the high-speed stroke end variable (value), there is a variable 1
There is one way to provide one degree of freedom necessary to
Or, it is provided as containing multiple links. In the case shown, the means include a link (3) pin-connected to the support fork Q61 of the speed change ring (4) and a support element 121I whose position can be changed. The link (■) is provided with a pin that engages with the cam groove of the grooved cam 071 and a long hole that engages with the pin on the support element QD, thereby controlling the reciprocating movement given to the speed change ring (4). The high-speed side stroke end is changed by aligning the indicator (■) on the support element Qυ to an appropriate position on the scale (■). In addition, 10,000 ■ is the supporting element Qυ
This is a fixing screw.

The lift curve of the grooved cam (171) is as illustrated in FIG.
It can be trapezoidal, sine-shaped, chevron-shaped, etc. Those with a trapezoidal lift curve are used to open and close shutters and large valves,
Alternatively, it is suitable for cases where a high speed in the middle of the stroke is required, such as when lifting and lowering heavy objects, and those with a sinusoidal lift curve are suitable for similar operations one after another, such as the intermittent feeding of a conveyor. Suitable when repetition is required. Also, for those with a chevron-shaped lift curve, when it is required to decelerate immediately after reaching the maximum speed (for example,
Suitable for centrifugal dehydrators (for draining laundry).

Groove cam 07+ determines which part of the micro speed range is used.
(generally speaking, the position at the end of the stroke performed by the cam, lever, or combination thereof that provides reciprocating movement to the speed change ring (4)).

Points A, B, O, and D in FIG. 2 are used to show that the magnitude of the torque applied to the output shaft (2) at the stroke end varies depending on the selection of the stroke end. A, B, C, and D are selected points, and T4, T2, T5, and T4 are torque values at these points. An example of a case where the torque value T1 is selected to be a relatively small value, such as the stroke end indicated by point A, is in the case of an article lifting device. In an article lifting device, it is desirable to accurately lift the article, and a special control device is required to keep the positional deviation within ±2 mm, but the device according to the present invention This control device is replaced by a simple stopper piece, which stops lifting of the article when a relatively small force corresponding to the torque T1 applied to the output shaft (2) at point A is applied. When the lifting of the article is completed, the power to the induction motor driving the transmission is turned off, but due to the irreversibility of the transmission (when the transmission ring is in a position that makes the rotational speed of the output shaft zero or close to zero, The gear ratio (rotational speed of the input shaft/rotational speed of the output shaft) is extremely large, and the input shaft cannot be rotated from the output shaft side.) Therefore, the object to be lifted can be lifted accurately by the stopper piece. Stay in position.

An example of a case where the torque value T2 is selected to be a somewhat large value as indicated by point B at the stroke end is in the case of a shutter opening/closing device. This device requires that a shutter with a considerable width be closed without leaving any gaps, and the selection of point B is along this line.

As the stroke end is indicated by point C or point D, the torque value T3, T
An example of a case where 4 is selected to be a considerably large value is the case of a large pulp opening/closing device. In this device, the seating force between the valve body and the valve seat is required to take a sufficiently large value, so points C, D, etc., which have large torque values, are selected depending on the required seating force. It is.

In the case of a punching press or a shearing device for shaped steel, the stroke end is a point Q that exhibits a torque value close to the maximum torque -8. In this case, the moment the punching or shearing operation is completed, the torque applied to the output shaft becomes zero, so the width W of the torque stall area is also expanded as shown by W'.

After the friction continuously variable transmission gives a reciprocating stroke to the speed change ring, the direction of rotation of the input shaft is reversed to perform a reverse operation. The direction of rotation of the input shaft is reversed by manually or automatically switching the operating circuit of the induction motor for driving the input shaft. This changeover occurs when a point is reached in the case of large pulps or in the case of shutters that require opening and closing, or cyclically in the case of intermittent drive to conveyors one after the other or in the case of equipment that performs shearing one after the other. , and is done automatically. 1
The friction continuously variable transmission according to the present invention as described above and described above is characterized by the torque characteristics that the friction continuously variable transmission of the type mentioned above exhibits near the point where the rotational speed of the output shaft becomes 0, and the irreversibility thereof. is used in a wide range of fields.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view showing an example of a continuously variable friction transmission according to the present invention, FIG. 2 is a drawing for explaining the torque characteristics of the transmission shown in FIG. 1, and FIG. 3 is a portion of the grooved cam shown in FIG. 1. FIG. 4 is a diagram illustrating the lift curve of the grooved cam.

Claims (1)

[Scope of Claims] A speed change ring is provided that is commonly frictionally engaged with a plurality of conical trochanters that perform planetary motion, and as the point of frictional engagement of the speed change ring with respect to the conical trochanters is further away from the apex of the cone, the output shaft is In the differential type which reduces the rotation speed to bring the rotation ψ speed to 0, a speed change operation device is provided which is driven by the output shaft through a mechanical deceleration means and gives a reciprocating movement to the speed change ring, The low-speed stroke end of the reciprocating motion that the rotation of the output shaft gives to the speed change ring is selected to make the rotational speed of the output shaft fine/JS, and the high-speed stroke end of the reciprocating motion is selected to make the rotation speed of the output shaft fine/JS. A continuously variable friction transmission characterized by being provided with means for selecting a maximum speed for changing.