JPS6212908Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable speed clutch device for use in driving, for example, a blower.

As shown in FIGS. 1 and 2, a conventional variable speed clutch device has a clutch plate 2 spline-fitted to an input member of an input shaft 1, and an output member 4 integrally provided to an output shaft 3. The output member 4 is provided with a clutch piston 6 that engages and disengages the clutch plates 2 and 5, and the clutch plates 5 are arranged alternately with spline-fitted clutch plates 5. , 5 is provided, a piston chamber 9 is provided on the opposite side of the clutch plate pressing surface 8 of the clutch piston 6, and a supply port 10 of this piston chamber 9 is connected to a hydraulic source 11. When trying to increase the rotational speed of the output shaft 3 in the meantime, the rotational speed control valve 1
A centrifugal control valve 12 is provided which has the function of increasing the hydraulic pressure from the line 27 applied to the clutch piston 6 by increasing the command pressure from the line 26 by operating the valve 4.

In this conventional system, when the rotational speed of the output shaft 3 decreases below a set value, the centrifugal control valve 12
This increases the hydraulic pressure applied to the clutch piston 6, increases the force with which the clutch piston 6 presses against the clutch plates 2 and 5, and reduces the slippage of the clutch plates 2 and 5 against the spring 7. When the rotational speed of the output shaft 3 increases more than the set value, it is pressed to increase the slip degree and return it to the set value. In this way, the rotational speed of the output shaft 3 is kept constant. As shown in FIG. 2, the conventional rotational speed control valve 14 used for setting the rotational speed opens the input port 18 when the right end of the spool 17 is pushed by the setting adjustment rod 15 via the spring 16. The oil flowing from the output port 19 to the output port 19 increases, and the oil flowing to the drain port 20 decreases, and the back pressure applied from the output port 19 to the left end of the spool 17 increases, keeping the spool 17 in balance. The movable valve body 22 of the centrifugal control valve 12 is moved to the port 23 by oil flowing out from the port 19.
The clutch piston 6 reduces the slit degree of the clutch plates 2 and 5 by squeezing the oil flowing from the port 24 to the drain port 25 in the axial direction, and increases the hydraulic pressure applied to the clutch piston 6. The rotation speed can be set high.

However, in such conventional systems, the hydraulic power source 1
1 stops due to a malfunction or the like, the hydraulic pressure applied to the clutch piston 6 disappears, the action of the clutch piston 6 to press the clutch plates 2 and 5 is released, and the clutch plates 2 and 5 completely slip and the input shaft 1 The rotation is not transmitted to the output shaft 3, and the rotation of, for example, a blower installed on the output shaft 3 stops, and as a result, the combustion air that was being blown by the blower to the boiler is stopped, and the equipment attached to the boiler is This may not only cause the equipment to stop working, but also lead to a serious accident.

The present invention has been developed in view of these points, and an object thereof is to provide a variable speed clutch device that does not stop rotation transmission from the input shaft to the output shaft even if the hydraulic power source stops.

Next, one embodiment of the present invention will be explained based on FIGS. 3 to 7.

A ring-shaped clutch plate 33 spline-fitted to the outer peripheral surface of the input member 32 of the input shaft 31; and a ring-shaped clutch plate 36 spline-fitted to the inner peripheral surface of the output member 35 integrally provided to the output shaft 34. are arranged alternately, and a ring-shaped clutch piston 38 is provided in the ring-shaped hollow portion 37 of the output member 35 to be able to move forward and backward in the axial direction, and which engages and disengages the clutch plates 33 and 36. 39 is a bearing.

Further, a plurality of coil springs 41 are fitted around the circumference of the output member 35 to bias the clutch piston 38 in the direction of fitting the clutch plates 33 and 36, that is, in the right direction in the figure. Provided in the hole 42.

Further, a hydraulic pressure supply port 46 is provided in the piston chamber 45 on the same side as the clutch plate pressing surface 44 of the clutch piston 38, and a hydraulic pressure supply port 46 is provided between the supply port 46 and a hydraulic pressure source 47 to increase the rotational speed of the output shaft 34. A centrifugal control valve 51 is provided which has the function of reducing the hydraulic pressure applied to the clutch piston 38 by operating the rotational speed control valve 63 and lowering the command pressure from the line 64 when the clutch piston 38 is to be operated.

In this centrifugal control valve 51, a spool valve 55 having an outer small diameter portion 52 and an axially-side large diameter portion 53 is provided on the output member 35 so as to be slidable in the radial direction, and a valve chamber 57 is provided relative to the annular groove 54.
A port 59 communicating with a line 58 from the hydraulic source 47, a port 61 communicating with a line 60 to the supply port 46 of the piston chamber 45, and a drain port 66 are provided on the side wall of the large diameter portion 53.
2 is provided with a rotation speed control valve 63 for adjusting the pressure for adjusting the rotation speed from the hydraulic pressure source 47 and a port 65 into which the hydraulic pressure supplied via a line 64 flows.

Then, the motor 71 is driven in the oil pressure source 47 to operate the pump 72, and the oil sucked up from the tank 73 through the strainer 74 is kept at a constant pressure at the pressure regulating valve 75 at the discharge part, and the oil is passed through the line 58. The oil that is forced into the port 59 of the centrifugal control valve 51 and is throttled into the small diameter portion 52 from this port 59 flows into the piston chamber 45 via the annular groove 54, port 61, line 60 and supply port 46, and is then connected to the clutch. Push the piston 38 to the left in the figure. In the centrifugal control valve 51, this pressing force is the product of the area difference between the large diameter portion 53 and the small diameter portion 52 and the pressing force acting on the inner diameter side as a thrust, and the rotational speed control valve 6
The sum of the thrust of the product of the command pressure from 3 and the area of the large diameter portion 53 and the centrifugal force of the spool valve 55 acts in the outer diameter direction.

In this balance between the two, the inflow port 59 and the drain port 66 are throttled by the small diameter portion 52 and the large diameter portion 53, respectively, and the clutch oil pressure applied from the port 61 to the piston chamber 45 via the line 60 is controlled and rotated. number is set.

At this time, if the rotational speed of the output shaft 34 decreases below the value set by the rotational speed control valve 63,
The centrifugal force applied to the spool 55 provided on the output member 35 integrated with the output shaft 34 also decreases, causing the balance in the centrifugal control valve 51 to collapse, causing the spool 55 to reduce the area between its large diameter portion 53 and small diameter portion 52. It moves in the axial direction by the thrust generated by the differential hydraulic pressure, narrows the port 59, and also closes the drain port 66.
to lower the hydraulic pressure supplied to the piston chamber 45,
The clutch piston 38 is relatively strongly pressed in the direction of the clutch plates 33, 36 by the coil spring 41, the degree of slip of the clutch plates 33, 36 is reduced, and the rotational speed of the output shaft 34 is increased and returned to the set value. .

Conversely, when the rotational speed of the output shaft 34 increases beyond the set value, the reverse action returns it to the set value.

In this way, the rotational speed of the output shaft 34 is kept constant at the set value.

Further, when the rotational speed control valve 63 is adjusted to lower the control oil pressure supplied to the port 65 of the centrifugal control valve 51, the spool 55 similarly moves in the axial direction to narrow the port 59 and drain port 66.
is opened to lower the oil pressure supplied to the piston chamber 45, and the clutch piston 38 is moved by the coil spring 4.
1, the clutch plates 33, 36 are pressed more strongly, the degree of slip of the clutch plates 33, 36 is reduced,
The rotational speed of the output shaft 34 increases. The relationship between the control oil pressure of the line 64 supplied to the port 65 and the rotational speed of the output shaft 34 is shown by a solid line in FIG. Note that the straight line indicated by a dotted line in FIG. 5 is the characteristic of the conventional example shown in FIG.

Furthermore, if the hydraulic power source 47 stops due to a failure of the hydraulic pump or a leak in the hydraulic system, hydraulic pressure is not supplied to the piston chamber 45, so the clutch piston 38 is operated with maximum force by the coil spring 41. The clutch plates 33 and 36 are pressed to the right by
The rotation of the input shaft 31 is transmitted to the output shaft 34 without slipping, and at least the output shaft 34 is prevented from stopping.

As shown in FIG. 6, the rotational speed control valve 63 suitable for setting the rotational speed in this embodiment is configured to move the right end of the spool 83 to the left in the figure by means of a setting adjustment rod 81 via a spring 82. When pushed, the oil flowing from the input port 84 to the output port 85 is throttled and reduced by the small diameter portion 86, and the oil flowing to the drain port 87 increases due to the opening of the large diameter portion 88. Since the urging pressure of the spring 82, the hydraulic pressure of the area difference between the small diameter portion 86 and the large diameter portion 88, and the urging pressure of the spring 89 are kept in balance, the output port 85 is connected to the port of the centrifugal control valve 51. The control hydraulic pressure supplied to the piston chamber 45 decreases, and the spool 55 of the centrifugal control valve 51 moves in the axial direction, narrowing the port 59 and opening the drain port 66 to lower the hydraulic pressure supplied to the piston chamber 45, and the coil spring By increasing the pressing force of the clutch piston 38 by the clutch plate 3
3 and 36 can be reduced, and the rotational speed of the output shaft 34 can be set high. and the seventh
As shown in the figure, the relationship between the movement stroke of the setting adjustment rod 81 to the left in the figure and the rotational speed of the output shaft 34 is proportional.

As described above, according to the present invention, the spring 41 which urges the clutch piston 38 in the direction of fitting the clutch plates 33 and 36, and the clutch plate pressing surface 44 of the clutch piston 38 are connected to each other. A piston chamber 45 is provided on the same side, and a supply port 4 for the hydraulic pressure of this piston chamber 45 is provided.
6 and the hydraulic power source 47, the operating hydraulic pressure applied to the clutch piston 38 is reduced by operating the rotational speed control valve 63 and lowering the command pressure from the line 64. Since the centrifugal control valve 51 having the function of reducing the pressure is provided, when the hydraulic power source 47 stops, the spring 4
1, the clutch plates 33 and 36 are fitted together, and the rotation of the input shaft 31 is directly transmitted to the output shaft 34, and although the rotational speed of the output shaft 34 cannot be controlled, at least the output shaft 34 is prevented from stopping. This prevents the blower connected to the output shaft 34 from suddenly stopping the air blowing to the boiler.

[Brief explanation of the drawing]

Figure 1 is a sectional view of a conventional variable speed clutch device.
Fig. 2 is a sectional view of the rotational speed control valve, Fig. 3 is a sectional view showing an embodiment of the variable speed clutch device of the present invention, Fig. 4 is a sectional view of the centrifugal control valve, and Fig. 5 is a sectional view of the centrifugal control valve.
6 is a sectional view of the rotational speed control valve, and FIG. 7 is a graph showing its operating characteristics. 31...Input shaft, 33...Clutch plate, 34...
...output shaft, 35...output member, 36...clutch plate, 38...clutch piston, 41...spring, 44...clutch plate pressing surface, 45...piston chamber, 46...supply port, 47... Hydraulic source, 51
... Centrifugal control valve, 52 ... Small diameter section, 53 ... Large diameter section, 54 ... Annular groove, 55 ... Spool valve, 5
7... Valve chamber, 58... Line, 59... Port,
60... Line, 61... Port, 62... Valve chamber, 63... Rotation speed control valve, 65... Port,
66...Drain port.

Claims (1)

[Scope of utility model registration request] Clutch plates 33 spline-fitted to the input member 32 of the input shaft 31 and clutch plates 36 spline-fitted to the output member 35 integrally provided on the output shaft 34 are arranged alternately, A clutch piston 38 is provided that engages and disengages the clutch plates 33 and 36.
Spring 4 that biases 3 and 36 in the direction of fitting
1, and a piston chamber 45 is provided on the same side as the clutch plate pressing surface 44 of the clutch piston 38,
A centrifugal control valve 51 is provided between the hydraulic pressure supply port 46 of the piston chamber 45 and the hydraulic pressure source 47, and the centrifugal control valve 51 has an outer small diameter portion 52 and an axial large diameter portion 53. A spool valve 55 having an annular groove 54 is provided in the output member 35 so as to be slidable in the radial direction, and a port 5 communicating with a line 58 from a hydraulic power source 47 is provided on the side wall of the valve chamber 57 relative to the annular groove 54.
9, a port 61 communicating with a line 60 to the piston chamber 45, and a drain port 66 are provided, and the hydraulic pressure supplied from the hydraulic source 47 via the rotation speed control valve 63 to the valve chamber 62 for the large diameter portion 53 is provided. This centrifugal control valve 5 is provided with an inflow port 65.
1, when the rotation speed of the output shaft 34 is to be increased, the rotation speed control valve 63 is operated to lower the command pressure from the line 64, thereby reducing the hydraulic pressure applied to the clutch piston 38. Variable speed clutch device.