JPH0623817Y2 - Swivel joint for high pressure fluid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a swivel joint for high-pressure fluid that introduces high-pressure fluid from a fixed body into a rotating body.

[Conventional technology]

Conventionally, there has been provided a high-pressure fluid swivel joint for guiding high-pressure fluid from a fixed body into a rotating body by using lubricating oil to enhance the sealing effect of the high-pressure fluid and to smoothly rotate the rotating body ( For example, JP-A-57-13
No. 7792, No. 61-184188, No. 61
-184189 gazette etc.).

That is, in such a high-pressure fluid swivel joint, in order to prevent the high-pressure fluid from leaking from the passage that connects the flow passage inside the fixed body and the flow passage inside the rotating body,
A packing is provided between the fixed body and the rotating body, and lubricating oil having the same pressure as the high-pressure fluid is supplied to the opposite side of the packing from the passage from the outside. The leakage of oil is prevented and the rotation of the rotating body is made smooth by the action of the lubricating oil.

However, in the conventional swivel joint for high-pressure fluid, a device for separately supplying a pressure of lubricating oil, that is,
Since a cylinder provided with a piston (a part of the high-pressure fluid is branched and introduced to one side of the piston and the lubricating oil to be supplied is supplied to the other side), the number of parts is large. Therefore, there are drawbacks that it is not possible to reduce the size and the cost is inevitable.

[Problems to be solved by the device]

The present invention eliminates the above-mentioned drawbacks of the prior art, can reliably prevent leakage of high-pressure fluid, can smoothly rotate the rotating body, and has a simple structure, small size, and low cost. Furthermore, it is an object of the present invention to provide a swivel joint for high pressure fluid in which the amount of oil and fat leakage is small.

[Means for Solving the Problems]

In order to solve the above problems, the present invention is directed to fixing either one of a shaft portion in which a high-pressure fluid passage is provided and a receiving portion into which the shaft portion is inserted, and the other to one. In a high-pressure fluid swivel joint that rolls and rotates with respect to one another to guide high-pressure fluid from the one side to the other side, at a suitable position in the rotation axis direction, between the shaft portion and the receiving portion, a cylindrical space and one or more A stepped cylindrical space having a small diameter on one end side and a large diameter on the other end side is formed so as to sequentially communicate with each other along the rotation axis direction, and the flow path of the shaft part and the flow path of the receiving part are formed. A communication passage communicating with the cylindrical space is provided so as to also communicate with one end of the cylindrical space in the rotation axis direction, and an annular ring slidable in the rotation axis direction on the one end side of the cylindrical space. A movable seal body is provided, and the movable seal body is provided in the cylindrical space with steps. An annular movable seal body having a step is provided on each end side so as to be slidable in the rotation axis direction across the step, and in each of the tubular space and the other end side empty space in each of the stepped tubular spaces. The oil and fat are hermetically sealed.

[Action]

According to the present invention, the communication passage communicating between the flow passage of the shaft portion and the flow passage of the receiving portion is also communicated with one end of the cylindrical space formed between the shaft portion and the receiving portion. Since an annular movable seal body that is slidable in the rotation axis direction is provided on the one end side in the cylindrical space, when the high pressure fluid is introduced, the pressure of the high pressure fluid is changed to the communication passage. Via one end of the movable seal body. Therefore,
The movable seal body tends to move toward the other end. Therefore, a tubular space with a step is formed in which one or more one end side has a small diameter and the other end side has a large diameter, and the stepped tubular space slides in the rotation axis direction across the step on the one end side. Since movable movable seal bodies with steps are provided respectively, and oils and fats are respectively sealed inside the cylindrical space and the empty chamber on the other end side of the stepped cylindrical spaces, the steps can be moved. The seal body also tries to move to the other end side, and the pressure of each oil and fat increases at the same time. Then, when the forces received from the both sides of the movable seal body and the movable seal bodies with steps become equal, these stop. At this time, the pressure of the oil and fat sealed in the chamber on the other end side in the cylindrical space becomes substantially equal to the pressure of the high-pressure fluid, and is sealed in the chamber on the other end side in each stepped cylindrical space. The pressure of each oil is reduced according to the area ratio between the one end and the other end of each movable seal with step, and the pressure of the oil sealed on the other side is the pressure of the high-pressure fluid. In contrast, the pressure becomes a constant small pressure.

As described above, according to the present invention, the pressures of the high-pressure fluid and the oil on both sides of the movable seal body are automatically made substantially equal, so that the leakage of the high-pressure fluid is almost completely prevented.

Since a pressure based on the pressure of the high-pressure fluid is applied to the oil and fat, the oil and fat leaks though it is a very small amount, and the amount gradually decreases. However, the stop positions of the movable seal body and the movable seal bodies with steps are only moved toward the other end side in accordance with the leakage of oil and fat, and the high-pressure fluid sealing effect is maintained. However, if the oil or fat completely disappears, the sealing effect will be lost, so that the oil or fat is replenished as appropriate based on the usage time.

Further, although the oil and fat tends to leak due to the pressure based on the pressure of the high pressure fluid, in the present invention, the pressure of the oil and fat sealed on the other side as described above has a small constant ratio to the pressure of the high pressure fluid. Since it becomes a pressure, the oil and fat will try to leak at that small pressure, and the amount of oil and fat leakage will be reduced compared to the case where the oil and fat will leak to the outside at the same pressure as the pressure of the fluid under pressure, saving oil and fat. The number of replenishments can be reduced.

Further, the lubricating action of the oil and fat also makes it possible for the rotating body, which is either the shaft portion or the receiving portion, to rotate smoothly.

In the present invention, the pressures of the high-pressure fluid and the oil on both sides of the movable seal body are automatically substantially equalized by the action of the movable seal body and the stepped movable seal body as described above. Unlike swivel joints for fluids, it does not require a device to supply special lubricating oil under pressure,
The configuration can be simplified, the size can be reduced, and the cost can be reduced.

[Embodiment] The present invention will be described below based on an embodiment shown in the drawings.

FIG. 1 is a longitudinal sectional view showing a swivel joint for high pressure fluid according to the present invention.

In FIG. 1, (1) is a shaft portion, and (2) is a receiving portion into which the shaft portion (1) is fitted. In this embodiment, the shaft portion (1) is a support (3 ) Is fixed to the shaft portion (1) by a nut (4).

In the case of the embodiment shown in FIG. 1, the shaft portion (1) has the receiving portion (2).
Is not completely penetrated, but the front end of the shaft portion (1) is positioned inside the receiving portion (2).

Further, inside the shaft portion (1), a high-pressure fluid flow path (5) opened at both ends thereof is provided, and a high-pressure fluid supply hose (not shown) can be connected to the rear end opening portion (5a). ing.
Further, the shaft portion (1) is provided with a flange portion (6) for preventing the receiving portion (2) from slipping forward.

Further, the receiving part (2) is divided into a receiving part main body (2a) and an end cover (2b) for convenience of manufacturing, and these are integrally connected by a connecting bolt (7).

Further, the flow path (8) for the high-pressure fluid is provided inside the receiving part (2), but in the case of the embodiment shown in FIG.
(8) is provided so as to be opened forward so as to form the same straight line as the flow path (5) of the shaft portion (1), and the flow path (8) has the flow path of the shaft portion (1). High-pressure fluid is introduced from (5). The front opening side of the flow path (8) is a screw hole so that a hose joint (not shown) for receiving the supply of high-pressure fluid can be connected thereto.

In the case of the embodiment shown in the drawings, the end cover (2b) is provided with an inner flange portion (9), and the inner flange portion (9) and the flange portion (6) of the shaft portion (1) are A thrust bearing (10) is interposed between the bearings (2) to prevent the receiving portion (2) from slipping forward without hindering the rotation of the receiving portion (2). In addition, in FIG. 1, (11) is a dust seal.

In the present invention, the cylindrical space (12) and the one or more one end portions have a small diameter and the other end portion between the shaft portion (1) and the receiving portion (2) at an appropriate position in the rotation axis direction. Is a cylindrical space with a large diameter step
(13) and (14) are formed so as to sequentially communicate with each other along the rotation axis direction, as shown in the first illustration.

In the case of the embodiment shown in FIG. 1, the cylindrical space (12) is formed by providing an annular recess in the inner peripheral surface of the receiving part main body (2a) at the position of the front end part of the shaft part (1). Has been formed. In consideration of manufacturing convenience, the stepped cylindrical spaces (13) and (14) are formed by interposing annular spacers (15), (16) and (17) in the receiving part main body (2a). Is formed. It has a spacer
It goes without saying that the parts (15), (16) and (17) may be previously formed integrally with the receiving part main body (2a). The above spacer
The O-rings (18) and (19) are embedded in (15), the O-rings (20) and (21) are embedded in the spacer (16), and the O-rings (22) and the packing (23) are embedded in the spacer (17). Has been done.

In the case of the embodiment shown in FIG. 1, the stepped cylindrical space (13)
Although the number of (14) is two, the number is not limited and can be set arbitrarily.

Further, a communication passage (24) communicating between the flow passage (5) of the shaft portion (1) and the flow passage (8) of the receiving portion (2) is provided in the rotational direction of the cylindrical space (12). One end (end opposite the stepped cylindrical space (13))
Is also provided. In the case of the embodiment shown in FIG. 1, the communication passage (24) is formed by increasing the diameter of the opening at the rear end of the flow path (8) of the receiving portion (2).

Further, an annular movable seal body (25) slidable in the rotation axis direction is provided on one end side (communication passage (24) side) in the cylindrical space (12), and the stepped cylindrical shape Movable seal bodies (26) and (27) with an annular step, which are slidable in the rotation axis direction, are provided on one end side (communication passage (24 side) side of the spaces (13) and (14), respectively.

In the case of the embodiment shown in FIG. 1, a bush (30) in which O-rings (28) (29) are embedded is used as the movable seal body (25), and both are used as the movable seal body with steps (26) (27). Both bushings (34) with O-rings (31) (32) and packing (33) embedded
Is used. The bushes 30 and 34 are preferably made of a material having a small friction coefficient and high durability.

Furthermore, the vacant chambers (13a) (14a) (15) on the other end side of the cylindrical space (12) and the cylindrical spaces with steps (13) (14).
Fats (35), (36) and (37) are sealed in a) respectively.

In addition, in FIG. 1, (38), (39), and (40) are the above-mentioned vacant spaces (13
a) (14a) (15a) is a filling means for filling the oil (35) (36) (37), these are the supply port (41) for filling the oil
And a steel ball (42) for opening and closing the supply port (41), and a set screw (43) for closing the supply port (41) by pressing the steel ball (42) after filling the oil and fat. Has been done. Therefore, in the case of the embodiment shown in FIG. 1, the set screw (43) and the steel ball (42) are respectively removed and oil and fat are filled from the supply port (41), and then the steel ball (42) is inserted. And then press it down with the set screw (43) to put the oil (35) in the chambers (12a) (13a) (14a) respectively.
(36) (37) can be sealed. The movable seal body (25) and the stepped movable seal body (2
6) and (27) do not need to be arranged on the one end side in advance, and can be automatically moved to the one end part by filling with the oils (35), (36) and (37). Further, in FIG. 1, (44)
Reference numeral (45) is a breathing means for facilitating the movement of the stepped movable seal bodies (26) (27) at the time of assembly, and the constitution itself is the same as that of the filling means (38) (39) (40).

According to the high-pressure fluid swivel joint of the present invention having the above structure, when the high-pressure fluid is supplied from the opening (5a) at the rear end of the shaft (1), the high-pressure fluid flows inside the shaft (1). It is guided to the flow path (8) of the receiving part (2) through the path (5). At this time, the pressure of the high-pressure fluid is applied to the one end side of the movable seal body (25) through the communication passage (24). Therefore, the movable seal body (25) is moved toward the other end (first side).
Try to move to the right). For this reason, the movable seal bodies with steps (26) (27) also try to move toward the other end (to the right in FIG. 1), and the pressure of each oil (35) (36) (37) is changed. It will increase at the same time.

Then, when the movable seal body (25) and the movable seal bodies with steps (26) and (27) have equal forces received from both sides, they stop. At this time, the pressure of the oil (35) sealed in the empty space (12a) on the other end side of the cylindrical space (12) becomes substantially equal to the pressure of the high-pressure fluid, and the cylindrical space with each step (13 ) (14), the pressure of each oil (36) (37) sealed in the vacant chamber (13a) (14a) on the other end side is the same as that of one end of each stepped movable seal body (26) (27). The pressure is reduced in accordance with the area ratio with the other end, and the pressure of the oil (37) sealed on the othermost side is a pressure having a small constant ratio with respect to the pressure of the high-pressure fluid.

In this way, the pressures of the high-pressure fluid and the oil (35) on both sides of the movable seal body (25) are automatically made approximately equal, so that the leakage of the high-pressure fluid is almost completely prevented.

In addition, since the pressure based on the pressure of the high-pressure fluid is applied to the fats and oils (35), (36) and (37), the fats and oils (35), (36) and (37) leak even though they are very small, and the amount gradually decreases. It is something to keep up.
However, the stop position of the movable seal body (25) and each stepped movable seal body (26) (27) is moving toward the other end side in accordance with the leakage of the grease (35) (36) (37). It ’s just
The sealing effect of the high-pressure body is maintained. However, if the fats (35), (36) and (37) are completely lost, the sealing effect is lost, so that the fats and oils are appropriately replenished based on the usage time.

Further, although the oils (35) (36) (37) try to leak due to the pressure based on the pressure of the high pressure fluid, the pressure of the oil (37) sealed on the other side as described above is higher than that of the high pressure fluid. Since the pressure is a constant small pressure relative to the pressure, the oil (37) attempting to leak to the outside will try to leak at that small pressure, and the oil (37) will leak to the outside at the same pressure as the pressure of the high-pressure fluid. As compared with the case of attempting to leak the oil and fat, the amount of oil and fat leakage is reduced, and it is possible to save the oil and fat and reduce the number of times of replenishment.

In addition, the lubricating effect of the above oils (35) (36) (37)
The rotation of the rotating body, which is either the (1) or the receiving part (2), is smooth.

Then, as described above, the movable seal body (25) and the stepped movable seal bodies (26, 27) are automatically operated to automatically move the movable seal body (2
6) The pressure of the high-pressure fluid and oil (35) on both sides of (27) automatically becomes approximately equal.Unlike the conventional swivel joint for high-pressure fluid, a device that supplies special lubricating oil under pressure is provided. It is possible to achieve simplification of the configuration, downsizing, and cost reduction without the need.

Next, FIG. 2 is a longitudinal sectional view showing an example of a high-pressure fluid rotary injection device using the high-pressure fluid swivel joint of the present invention. The rotary injection device shown in FIG. 2 uses the swivel joint for high pressure fluid shown in FIG. 1 as it is. In FIG. 2, the same components as those of the embodiment of FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

In FIG. 2, (46) is an injection nozzle, and although not shown in detail in the drawing, a plurality of injection nozzles are provided radially and symmetrically with respect to the rotation axis. Therefore, in the case of FIG.
The flow path (8) inside (2) is provided so as to correspond to each nozzle (46).

Further, in FIG. 2, (47) is a sprocket, and a roller chain (not shown) is suspended between the sprocket (47) and the sprocket of the output shaft of the motor (not shown) to drive the motor. When this is done, the receiving part (2) will rotate automatically.

According to the rotary injection device shown in FIG. 2, high-pressure water or the like can be rotary-injected from the injection nozzle (46) to remove asphalt or concrete, and further to wash the wall surface of railway vehicles, buildings, etc. It can be used for cleaning the inner wall surface.

FIG. 3 is a vertical cross-sectional view showing another example of a high-pressure fluid rotary injection device using the high-pressure fluid swivel joint of the present invention. The same components as those in the embodiment shown in FIG. 1 or 2 are designated by the same reference numerals and the description thereof will be omitted.

In the case of the embodiment shown in FIG. 3, the receiving part (2) is fixed to a support (not shown), and the shaft part (1) is adapted to rotate with respect to the receiving part (2). It is different from the embodiment shown in FIG. 1 or 2 above in that a high-pressure fluid is introduced from the flow passage (8) to the flow passage (5) of the shaft portion (1), and it is substantially the same. Is the first
This is similar to the embodiment shown in FIG.

However, in the case of the embodiment shown in FIG. 3, the head portion (48) is integrally screwed to the tip of the shaft portion (1), and the injection nozzle (46) and the sprocket (47) are attached to the head portion (48). ) Is provided. In addition,
In FIG. 3, (49) is an O-ring and (50) is a plain bearing.

In FIG. 3, the sprocket (47) and the injection nozzle (46) are removed, and the flow path (5b) near the injection nozzle (46) is also removed. Instead, the flow path indicated by the imaginary line in FIG. If (5c) is provided, it can be used as a normal high-pressure fluid swivel joint.

FIG. 4 is a vertical cross-sectional view showing still another example of a high-pressure fluid rotary injection device using the high-pressure fluid swivel joint of the present invention. The same components as those of the embodiment shown in FIG. 1, FIG. 2 or FIG. 3 are designated by the same reference numerals and the description thereof will be omitted.

In the case of the embodiment of FIG. 4, the receiving portion (2) is fixed and the shaft portion (1) is adapted to rotate. Basically the same as the embodiment of FIG. ) Is completely penetrated with respect to the receiving part (2). Therefore, the flow path (8) of the receiving part (2) is provided in the radial direction and is opened to the outside laterally, and the shaft part
The end of the flow channel (5) of (1) is opened in a cross shape in the side part corresponding to the flow channel (8) of the receiving part (2), and between the flow channels (5) and (8) They are communicated with each other by an annular communication passageway (24). For this reason,
In the case of the embodiment shown in FIG. 4, the cylindrical space (12), the cylindrical spaces with steps (13) and (14), the movable seal body (25), and the steps are symmetrically provided on both sides of the communication passage (24). 2 with movable seal body (26) (27) etc.
They are provided in pairs.

In the case of the embodiment shown in FIG. 4, the sprocket (47) is fixed to the end of the shaft (1) by a nut (51). Further, in FIG. 4, (52) is a plain bearing.

Also in the case of the embodiment of FIG. 4, it can be used as a normal high-pressure fluid swivel joint by changing the injection nozzle (46) like the embodiment of FIG. Is.

Of course, the high-pressure fluid swivel joint of the present invention can be used not only in the rotary injection device for high-pressure fluid but also in various other applications.

[Advantages of the Invention] According to the present invention, leakage of high-pressure fluid can be reliably prevented, rotation of the shaft portion or the receiving portion, which is a rotating body, can be smoothly performed, and the structure is simple and downsized. The effect is that the cost can be reduced, the leakage amount of the fats and oils can be reduced, and the fats and oils can be saved and the number of replenishments of the fats and oils can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, FIG. 2 is a vertical sectional view showing an example of a high-pressure fluid rotary injection device using the present invention, and FIG. 3 is a high-pressure fluid using the present invention. FIG. 4 is a vertical cross-sectional view showing another example of the rotary injection device of FIG. 4, and FIG. 4 is a vertical cross-sectional view of the rotary injection device of high-pressure fluid utilizing the present invention. (1) …… Shaft section, (2) …… Reception section, (5) (8) …… Flow path, (12) ……
Cylindrical space, (13) (14) ... Cylindrical space with steps, (12a) (13a)
(14a) …… Vacancy, (24) …… Communication passage, (25) …… Movable seal, (26) (27) …… Movable seal with step, (35) (36) (37)
…… Fats and oils.

Claims (1)

[Scope of utility model registration request] 1. One of a shaft portion having a high-pressure fluid flow passage provided therein and a receiving portion into which the shaft portion is inserted is fixed, and the other is rotatively rotated with respect to the other. ,
In a high-pressure fluid swivel joint for guiding high-pressure fluid from one side to the other side, a cylindrical space and one or more one end side with a small diameter are provided between the shaft portion and the receiving portion at an appropriate position in the rotation axis direction. A cylindrical space with a step on the other end side having a large diameter is formed so as to sequentially communicate with each other along the rotation axis direction, and communicates between the flow passage of the shaft portion and the flow passage of the receiving portion. The passage is provided so as to also communicate with one end of the tubular space in the rotation axis direction, and an annular movable seal body slidable in the rotation axis direction is provided on the one end side of the tubular space. An annular movable seal body having a step across the step and slidable in the rotation axis direction is provided on the one end side in each of the stepped tubular spaces, and the tubular space and each stepped tubular shape are provided. Oil and fat should be packed in the chamber on the other end side of the space. Swivel Jiyo Into a high pressure fluid, characterized in that to become to.