JPS632274Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a safety device for preventing an operating body operated by fluid pressure or the like from falling due to its own weight.

Generally, when an actuating body operated by a fluid pressure cylinder or the like is installed perpendicular to the floor and is used in a manner where it is affected by gravity, in order to maintain the cylinder piston at the rising end for a long time, The device is locked by the action of an electromagnetic switching valve, or a check valve or the like is built into the circuit to prevent it from falling due to its own weight.

However, it is difficult to completely prevent leakage with a fluid-based switching valve alone, and over a long period of time, the piston will descend due to the action of gravity, and the stopping position of the actuating body will gradually change, resulting in interference with other parts. There was a risk of trouble occurring due to interference, which was a safety problem.

For example, if the actuating body is applied to a tool changing device of a vertical machining center, if the changing arm deviates from the retracted position and rotates downward, it may interfere with the spindle tool. If this was applied, the meshing position of the gears would shift and there was a risk of unexpected accidents such as damage to the gears.

SUMMARY OF THE INVENTION An object of the present invention is to provide a safety device that is integrated into a cylinder device that operates an actuating body in order to solve the above-mentioned problems.

Examples thereof will be described below based on the drawings. Figure 1 shows a longitudinal cross-sectional view of a safety device in which the present invention is applied to a gear box, and Figure 2 is a longitudinal cross-sectional view of the safety device in which the present invention is applied to a gear box.
The sectional view and FIG. 3 are the same BB sectional views. It has an actuating body 22 which is disposed in the vertical direction so as to be affected by gravity and can be actuated in the axial direction by a fluid pressure cylinder or the like, and the gear 5 in the gear box 39 is activated by the operation of the actuating body 22. .
3, 24 and gears 5, 6, 42 which are slidably fitted to the spline shaft 7,
The actuating body 22 is arranged in parallel with the spline shaft 7 and is guided by the frame 1 at its upper part, and the shifter 4 is attached to the pin 2 on the outer periphery of the actuating body 22.
The piston 3 and the piston rod 13 of the cylinder 2 are formed in the intermediate part, and the lower part has a step part 16 which becomes the small diameter shaft 28, and the tip part is connected to the gears 5 and 6. are provided with detection dogs 29, 29. A block 26 having pressure oil supply and discharge ports 8 and 17 is connected to the lower part of the cylinder 2, and a block 27 having an eccentric horizontal hole 31 is connected to the lower part of the block 26. 31 is fitted with an engaging body 11 which is biased inwardly by a spring 14 and has stepped portions 38, 38 with its middle portion serving as a small diameter shaft 32. The interior position is restricted by stoppers 15, 15' protruding from the left and right entrance sides.

Further, a stay 33 is fixed to the lower part of the block 27, and limit switches 30, 30 are arranged above and below to detect the detection dogs 29, 29.

The block 26 has one side supply/discharge port 17 for pressure oil.
A communication passage 1 leading from the upper oil chamber 19 of the piston 3
8 are provided, and the hole 20 and the groove 34, the hole 3
5 to the oil chamber 21, and the supply/discharge port 8 to the lower oil chamber 9 of the piston 3.
It communicates with the oil chamber 12 through the hole 10, the groove 36, and the hole 37.

To explain the operation of the safety device having the above configuration, first, the spline shaft 7 is rotated by the operating body 22 shown in FIG.
The gears 5 and 6, which are slidably engaged in the axial direction of the The gears 5, 6 can be slid along the spline shaft 7 by moving the gears 5, 6 to When pressure oil is supplied, the piston rod 13 moves upward, so the actuating body 22
A shifter 4 coupled to the shifter 4 and gears 5 and 6 engaged therewith move along the spline shaft 7.

By the way, at this time, the pressure oil from the joint 41 in FIG.
via groove 36, hole 37, and oil chamber 1 in Fig. 2.
2. As a result, the engaging body 11 moves toward the stopper 15' due to the hydraulic pressure and the biasing force of the spring 14, and engages with the stepped portion 16 between the piston rod 13 and the small diameter shaft 28.

Therefore, after engaging as described above, the cylinder 2
Even if there is a problem such as a leakage of pressure oil from the oil chamber 9 or a power outage, and the piston rod 13 attempts to descend due to the action of gravity, its stopping position will not change because it is mechanically locked as described above.

Next, in order to switch gears 5 and 6 from this state, pressure oil is removed from the supply/discharge port 8, and conversely, pressure oil is supplied from the joint 41' through the supply/discharge port 17 and the communication path 18 to the oil chamber 19. supply

At this time, the pressure oil simultaneously flows through the hole 20 and the groove 34 into the hole 35 and the oil chamber 21, so the engaging body 11 moves toward the stopper 15 against the biasing force of the spring 14. Therefore, the engagement between the engaging body 11 and the stepped portion 16 is released, and the small diameter shaft 32 of the engaging body 11, together with its stepped portions 38, 38, is stopped in a positional relationship that appropriately matches the outer diameter of the piston rod 13. .

Therefore, the actuating body 22 becomes movable downward as the piston 3 descends, and at the same time the gears 5 and 6 engaged with the shifter 4 move downward along the spline shaft 7.

Note that the limit switches 30, 30 are operated by the actuating body 22.
When the moves vertically, its dogs 29, 29
has been detected and operation is being confirmed.

As explained above, the present invention is simple in that it is possible to mechanically lock the operating body in a safe direction at the same time as the raising action by hydraulic pressure, and on the other hand, when unlocking, the lock can be automatically released at the same time as it is lowered. This provides a safety device that operates reliably with a secure structure.

[Brief explanation of the drawing]

The drawings show an embodiment of a safety device in which the present invention is applied to a gear box. FIG. 1 is a longitudinal sectional view of the safety device, FIG.
It is a sectional view of B. DESCRIPTION OF SYMBOLS 1... Frame body, 2... Cylinder, 3... Piston, 4... Shifter, 5, 6... Gear, 7... Spline shaft, 11... Engaging body, 14... Spring, 1
6... Step portion, 22... Operating body, 31... Lateral hole,
39...Gear box.

Claims (1)

[Scope of utility model registration request] In order to configure a switching device for switching power transmission, an actuating body is disposed vertically in a frame body having a guide portion in a part and is movable in an axial direction by fluid pressure, and the actuating body is used to transmit power. In a cylinder device that stops and holds at each upper and lower position when switching, an actuating body is provided at one end upper part, the actuating body side is guided by a guide part of the frame body, and the intermediate part constitutes a piston of a fluid pressure cylinder, The lower end of the other end includes an operating shaft having a stepped portion having a narrow diameter, a block body provided on the side opposite to the operating body side of the cylinder device and slidably guiding the operating shaft stepped portion, and the block body includes: A horizontal hole bored to intersect the operating shaft at a position eccentric to the operating shaft axis, an engaging body fitted into the horizontal hole and pressed to one side, and defined at both ends of the engaging body. and passages bored in the cylinder so that the two oil chambers communicate with the supply and discharge ports of the cylinder, and when the actuating body is moved upward by the cylinder, the pressure is applied. When the engaging body moves, it engages with the stepped portion of the operating shaft, and when pressure oil is supplied to lower the operating body, the engaging body is moved by the pressure oil and disengages from the stepped portion. Features safety equipment.