JPH0559310B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a switching operation capable of switching the operation of a rotating valve body such as a butterfly valve or a ball valve to either manual or automatic operation.

(Prior art) A valve with a rotating valve body, such as a butterfly valve or a ball valve, has a valve stem connected to the rotating shaft of the valve body that extends outside the main body to serve as a drive shaft, and a driving force is applied to this valve stem. Connected and operating. Valve opening and closing operations can be performed automatically using fluid pressure or electrical driving force.
It is configured such that a switching device can switch between two types of operations: manual operation and manual operation. Normal valve opening and closing operations are performed automatically, and manual operation is required when testing a valve that has not yet been connected to the driving force for automatic operation, or in an emergency when the automatic operation mechanism is disabled for some reason. The valve is opened and closed by switching to the operation.

(Problems to be Solved by the Invention) A valve that selectively enables two types of operation, automatic operation and manual operation, is equipped with a manual operation consisting of, for example, a gear train on the upper part of the main body 1, as shown in FIG. A mechanism 2 and an automatic operation mechanism 3 consisting of a fluid pressure device are arranged on the drive shaft, and a switching mechanism 4 consisting of a clutch device is disposed between both mechanisms 2 and 3, so that both mechanisms 2 and 3 are connected to the drive shaft. The valve is opened and closed by selectively connecting and disconnecting the three mechanisms 2, 3, and 4, but forming and installing these three mechanisms 2, 3, and 4 separately increases the manufacturing cost of the valve.
In addition, the valve operating mechanism occupies an excessive amount of space, and the number of parts increases, resulting in a problem that maintenance is laborious and costly. Moreover, because of the manual operation mechanism and its switching mechanism, which are unnecessary except in specific cases such as test runs or emergencies, there are problems such as the overall size of the valve becomes large and the cost increases considerably. Ta.

(Means for Solving the Problems) The present invention aims to solve the above-mentioned problems found in conventional butterfly valves and ball valves that can be switched between automatic and manual operation.
A worm wheel is fixed to a drive shaft that is connected to an automatic operation mechanism and can open and close the valve body, and a worm gear that meshes with the worm wheel is connected to a manual handle shaft that is movable in the axial direction of the worm gear. It is characterized by a stopper that prevents movement and is lockably attached to the gearbox.

(Function) To switch from manual operation to automatic operation, release the lock and rotate the manual handle. Since the worm wheel does not rotate due to the load from the valve and automatic drive device via the drive shaft, the worm gear will rotate along with the handle shaft. Move in the axial direction of the handle shaft.
When the worm gear is removed from the worm wheel, the worm wheel can rotate freely, so the automatic operation mechanism can be activated to automatically open and close the valve body, completing the switch from manual to automatic operation. do.

Conversely, in order to switch from automatic operation to manual operation, the manual handle shaft is moved in the axial direction to reverse the handle shaft and engage the worm gear and the worm wheel. After the worm gear and worm wheel are completely engaged, a stopper is locked to prevent movement of the worm gear. This completes the switch from automatic operation to manual operation.

(Embodiment) A preferred embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Although the illustrated embodiment is applied to a butterfly valve, it can also be applied to a ball valve or other valve that is equipped with a rotating valve body and in which a drive shaft for driving the valve body extends outside the main body. Applicability will be easily understood by those skilled in the art.

In the figure, reference numeral 10 denotes a drive shaft that is connected to the disc-shaped valve body of the butterfly valve and can rotate the valve body, and is driven by fluid pressure such as air pressure or electrical energy as is conventionally known. The valve body is connected to a drive device and is driven by an automatic operation device to open and close the valve body. Reference numeral 11 denotes a worm wheel attached to the drive shaft 10, and a worm gear 12 meshing with the worm wheel 11 is movable in the axial direction and integrated in the rotation direction with a handle shaft 14 provided with a manual handle 13. It will be installed. Reference numeral 15 denotes a stopper that prevents the worm gear 12 from moving in the axial direction, and is inserted into the outer periphery of the handle shaft 14 so as to be movable in the axial direction. It extends outward through the. 17 is gearbox 16
The lock arm is disposed at the stopper 15 and engages with the outer end of the stopper 15 to prevent the stopper 15 from moving. Worm gear 12 to worm wheel 1
The state shown in FIG. 1 in which the stopper 15 is engaged with the worm gear 12 and the tip of the stopper 15 is in contact with the worm gear 12 to prevent its movement indicates a manual operation function state, and the stopper 15 is prevented from moving in the axial direction by the lock arm 17. has been done. When the manual handle 13 is manually rotated in the state shown in FIG. 1, the worm gear 12 is rotated via the handle shaft 14, and the worm wheel 11 that meshes with the worm gear 12 is rotated, so the drive shaft 10 is rotated and the valve is rotated. The body opens and closes.

To disconnect the manual operation, disengage the lock arm 17 and stopper 15, and then
5 is allowed to move freely in the axial direction. When the manual handle 13 is rotated in this state, the worm wheel 11 does not rotate because the load from the valve and automatic drive device is applied via the drive shaft 10, and the worm gear 12 is relatively moved along the handle shaft 14 to the stopper. Move while pressing 15. As shown in FIG. 2, when the worm gear 12 and the worm wheel 11 are completely disengaged, the worm wheel 11 becomes freely rotatable, so the automatic operating device is activated to automatically operate the valve. It can open and close its body.

Next, to enable manual operation, the manual handle 13 is reversed while pushing the stopper 15. The worm gear 12 is moved in the axial direction by pushing the stopper 15, and the worm gear 12 and the worm wheel 11 are engaged with each other by reversing the manual handle 13. After the lock arm 17 is completely engaged, the lock arm 17 is engaged with the stopper 15 to prevent it from coming off, and the state shown in FIG. 1 is returned. This connects the manual handle 13 and the drive shaft 10, making it possible to open and close the valve body by manual operation.

The locking of the stopper 15 is not limited to the illustrated lock arm 17, but a structure in which the stopper 15 is screwed into the gearbox 16, or any other desired locking mechanism can be applied. Further, the stopper and the lock mechanism may be of an integrated structure without being separated. Further, in the illustrated embodiment, the stopper 15 is adapted to move toward the manual handle 13, but it goes without saying that it may also be freely movable toward the opposite side (effects of the invention). According to the above, a worm wheel is fixed to a drive shaft that is connected to an automatic operation mechanism and can open and close a valve body, and a worm gear that meshes with the worm wheel is connected to a manual handle shaft that is movable in the axial direction of the worm gear. The stopper that prevents the valve from moving in the axial direction is lockably attached to the gearbox, so it is easy to switch between the manual operation mechanism and the drive shaft that opens and closes the valve, and the switching mechanism occupies less space. Since it is small and the number of parts is reduced, it is possible to reduce costs. Furthermore, since the switching mechanism only requires attaching a stopper and a mechanism for locking the stopper to a conventional manual operation mechanism, it can be applied to a commercially available valve by simply modifying its structure.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a manual operation switching mechanism according to the present invention, FIG. 2 is a view similar to FIG. 1 showing a state in which the manual operation is disconnected, and FIG. It is a front view. 10... Drive shaft, 11... Worm wheel,
12...Worm gear, 13...Manual handle,
14...Handle shaft, 15...Stopper, 16
...Gearbox, 17...Lock arm.

Claims (1)

[Claims] 1. A worm wheel is fixed to a drive shaft that is connected to an automatic operation mechanism and can open and close a valve body, and a worm gear that meshes with the worm wheel is connected to a manual handle shaft that is movable in the axial direction of the worm gear.
A valve operation switching device characterized in that a stopper for preventing axial movement of a worm gear is lockably attached to a gearbox.