JPS60121358A - Lever device for preventing transmission of overtorque - Google Patents

Abstract

PURPOSE:To prevent damage of parts by disposing a supprt pin and a support shaft on a shaft to which torque is transmitted, engaging the base end surface of a torque transmission lever with the support shaft and extending a spring between the forward end portion of the torque transmission lever and the support pin. CONSTITUTION:A support 41 is disposed at the center of the end surface of a shaft 38 to which torque is transmitted, and support shafts 42a, 42b are disposed symmetrically about the support pin 41. The base end surface of a torque transmission lever 46 is engaged with the support shafts 42a, 42b, and a spring 44 is extended between the forward end portion of the torque transmission lever 46 and the support pin 41. In this arrangement, when torque more than a fixed works upon the shaft 38 to which torque is transmitted, the torque transmission lever 46 is automatically released to control the working torque below a fixed value, so that related parts connecting with the shaft 3 to which torque is transmitted can be prevented from being damaged.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an overtorque transmission prevention lever device that prevents overtorque from being transmitted to equipment after the torque transmitted shaft, and more specifically, the present invention relates to a lever device for preventing overtorque from being transmitted to equipment after the torque transmitted shaft. Vane control lever, variable stator vane axial flow, centrifugal fan stator vane control lever,
The present invention relates to a lever device for preventing excessive torque transmission, which is effective when used as a guide vane control lever in a fan, blower, or compressor.

1 to 3 show general configuration examples of variable blade axial flow fans, in which a rotating hub 2 having a plurality of variable blades 1 is shown.
, 3 (the illustration shows an example of a double structure),
It is supported by a main bearing 4 and rotationally driven by an electric motor 5 to compress fluid from an inlet 6 as shown by an arrow 7 and guide it to a diffuser 8 .

The variable blade 1 is rotatably attached to the outer periphery of the rotary hub 2.3 via a thrust ball bearing 10 by a rotor blade pivot 9 provided integrally with the rotor blade pivot 9.
A slide shoe 12 is provided at the end of the rotation hub 11 via an arm 11, and the slide shoe 12 is connected to the rotating hubs 2 and 3.
The guide *15 is fitted between the guide rings 13 and 14 provided inside the guide ring 13 and 14.
By moving in the direction 16.17 along the axis center line,
Rotate all of the variable blades l simultaneously in the same direction and at the same angle 1
8 and can be adjusted.

Further, a control cylinder 2o is provided in the rotary hub 2, and the control cylinder 2o is fixed to the rotary hub 2 at one end, and the other side is fixed to the kite ring by a connecting member 19. The control cylinder 2o is for converting a small operating force into a large operating force according to the movement of the control rod 21, and the control cylinder 2o is provided with a pilot valve 22 and is connected to a hydraulic device 23. rotary joint 2
When the control rod 21 is moved in the direction 25, pressure oil from the hydraulic pump 26 of the hydraulic device 23 is introduced into the rod side chamber 27 of the control cylinder 20. As a result, the control cylinder 2o is contracted, and the guide ring 14 connected to the control cylinder 20 via the guide ring 13 and the interlocking rod 28 is increased in 16 directions, and the variable blade 1 is rotated. , - When the force control rod 21 is moved in the 29 direction, pressure oil is introduced into the cylinder head side chamber 3o and the control cylinder 20 is expanded, so that the guide rings 13, 14 are increased in the 17 direction and the variable blade 1 is moved. is adapted to rotate in the opposite direction to the above. In addition, 31 in the figure is the rotor blade pivot 9.
(shows the balance g+rI adjustment 11).

In the above-mentioned 414 configuration, when controlling the drive of the control rod 21, the control rod 21 is provided with a control shaft 33 that passes through the diffuser 8 via an operating lever 32, and a control lever 34 is fixed to the outer end of the control shaft 33. This is performed by operating a drive lever 37 in a control drive 36 connected via a connecting rod 35.

Therefore, even if the control cylinder 20 breaks down, the operating force of the drive lever 37 is transferred to the control shaft 33, control rod 21, and rotary joint 24 via the control lever 34.
, the pilot valve 22 and the like, there is a risk that excessive torque will be applied to these members or devices and cause them to be damaged.

That is, in general, when the torque required to drive a torque-transmitted shaft such as the control shaft 33 described in mI changes over time, if torque is applied indefinitely until the torque-transmitted shaft is driven, the related drive There is a risk that parts may break or deform due to high loads. In particular, the control cylinder 2o
When driving the spool valve of a hydraulically driven device such as, a large driving force is generated by hydraulic pressure with a small driving force, and there is no large load acting from the controller to the spool valve, so it is specially designed to be strong. do not have to. Therefore, if the hydraulic drive capability of a hydraulic drive equipment is lost due to some kind of accident, the reaction force that was previously supported by the hydraulic equipment may reach the spool valve, power transmission mechanism, and controller, which is not designed to support high loads. Failure to do so will lead to damage to these parts. Even if the hydraulically driven equipment is functioning normally, similar results will occur if the driving force exceeds this capacity.

In view of the above circumstances, the present invention has been made in order to provide a lever device for preventing excessive torque transmission, which prevents excessive torque from being transmitted to related parts after the torque-transmitted shaft.

Hereinafter, the present invention will be described in detail with reference to the drawings.

As shown in FIGS. 4 and 5, a flange plate 39 is fixed to the end face of the torque-transmitted shaft 38, and the flange plate 39 is
A flange plate 40 is appropriately spaced parallel to the flange plate 9, and a support pin 41 is installed in the center of the flange plate 39, and a support pin 41 is installed between the flange plates 39 and 40 at symmetrical positions on a straight line passing through the support pin 41. Support shaft 42a.

Install 42b in parallel. Further, a support point formed by the isosceles of the hanger member 43, in which the support point is arranged at each apex corner of an isosceles triangle, is pivoted to the support pin 41, and the other two support points are connected as required. One end of each tension spring 44, 44 is locked, and the other end of each spring 44, 44 is connected to the base end of the support shaft 42a.

A bolt 47.4 is inserted into the box-shaped torque transmission lever 46 from the proximal end in parallel with the arcuate surfaces 45, 45 that can be engaged with the torque transmission lever 42b.
7, and the tension of the spring 44.44 causes the arcuate surface 45.45 of the torque transmission lever 46 to be fixed to the support shaft 4.
2 and 42.

Now, in FIG. 5, it is assumed that torque Mo is applied to the torque transmission lever 46 in the direction of the arrow. Support 1To42a,
Assuming that the drag forces acting on 42b are Ra and Rb, the moment balance equation is as follows.

drag force F9 added to or reduced by the support shafts 42a, 42b due to
can be conveyed to. Then, the transmission torque Mo gradually increases, and while Rb increases, when Ra becomes zero or in a negative region, that is, the resistance between the support shaft 42a and the torque transmission lever 46 becomes zero, or a gap is created between them. and,
Transmission torque M.

teeth, =F, pz, +2Mmax ゛、　Mmax=　2Fy　z　.

Therefore, the torque transmission lever 46 does not transmit torque exceeding Mmar to the torque transmitted shaft 38, and the torque transmission lever 46
is released to the support shaft 42b' 2 fulcrums (see Fig. 6). At this time, the elongation of the springs 44 and 44 is almost the same as the initial state (even after release, there is almost no change in F and ?), so This device has a function of releasing a transmitted torque that exceeds a certain torque determined by device dimensions 11 and spring tension F3.

Therefore, if this device is used in place of the control shaft 33 and control lever 34 shown in FIGS. 1 and 2, excessive torque will not be transmitted to related parts after the control shaft 33.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and it goes without saying that additions and changes can be made without departing from the gist of the present invention.

As explained above, according to the overtorque transmission prevention lever device of the present invention, when a certain amount of torque is applied to the torque-transmitted shaft, the torque transmission lever is automatically released to reduce the operating torque to a certain m or less. Therefore, damage to related parts connected to the torque-transmitted shaft can be prevented.

In addition, this device does not apply the expansion and contraction phenomenon of the spring depending on the operating torque, but the initial tension of the splinter is maintained regardless of the operating torque, so it is easy to set the release torque, and this setting is easy. No deterioration occurs over time.

[Brief explanation of the drawing]

Figure 1 is a side view showing a general configuration example of a variable blade axial flow fan equipped with a torque transmission lever, Figure 2 is a perspective view showing the operating mechanism of the variable blade shown in Figure 1, and Figure 3 is a FIG. 4 is an exploded perspective view of the overtorque transmission prevention lever device of the present invention, and FIG. 5 is an assembled view corresponding to the V-V arrow view in FIG. 4. , FIG. 6 is an explanatory diagram showing the operating state. 38... Torque transmitted shaft, 41... Support bin, 42
a, 42b...Support shaft, 44...Spring, 45
...Arc surface, 46...Torque transmission lever.

Claims (1)

[Claims] 1) A support pin is provided at the end of the shaft to which the torque is to be transmitted, and a support shaft is provided at a symmetrical position sandwiching the support pin, and the proximal end surface of the torque transmission lever is engaged with the support shaft. A lever device for preventing excessive torque transmission, characterized in that a spring is stretched between the tip of the torque transmission lever and the support pin.