JPS6143997Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a sealing member for sealing the gap between the shaft that rotates the rotor of a pump such as a vane pump and a hole formed in the side of a case to allow the shaft to pass through. In particular, the present invention relates to a sealing member for a pump suitable for moving fluids such as liquid foods such as mayonnaise and dressings, cosmetics, and medicines that must be prevented from being contaminated with impurities.

Generally, a pump such as a vane pump is designed to cause fluid introduced into a case from an inlet, rotated by a rotor, and discharged from an outlet. The shaft that rotates the rotor is rotated by a drive source such as a motor attached outside the case. Therefore, a hole for inserting the shaft must be provided on the side of the case. This hole is naturally larger than the diameter of the shaft. Therefore,
A sealing member must be attached to the shaft and the case to prevent internal fluid from leaking through the gap between the shaft and the hole. Since the shaft rotates and the case is fixed, special measures are required to install the sealing members between them. Particularly in the case of pumps for fluids such as mayonnaise, cosmetics, pharmaceuticals, and other fluids that must be kept free from contamination with impurities, the structure of the sealing member is complicated because it cannot be sealed with oil such as grease. become.

An example of a conventional sealing member for a pump that prevents impurities from being mixed into the fluid to be transferred will be described with reference to FIG. A shaft 1 is rotatably attached to a shaft case 3 by bearings 2, 2. The end of the shaft case 3 on the side of the pump body is a flange 4, and a hole through which the shaft 1 passes is provided in the center of the flange 4.
This hole and the shaft are sealed by a conventionally known mechanical seal 5 to prevent oil in the shaft case 3 from leaking outside.

A spline 6 consisting of a linear groove is provided at the tip 1a of the shaft 1, and a rotor 7 is detachably attached thereto. Reference numeral 8 denotes a case, and the inner surfaces of both side surfaces 8a, 8a are parallel planes so as to rotate the rotor 7. This case 8 is provided with a flange 8c that is attached to and comes into contact with the flange 4 at a position away from the side surface 8a, and is connected to the side surface 8a by a connecting portion 8d. A hole is provided for passing the shaft 1 through the connecting portion 8d, and the connecting portion of this hole is enlarged to form a space 9. A sealing member is installed in this space 9 to seal the gap between the hole and the outer surface of the shaft 1. This sealing member mainly includes a support body 10 fixedly attached to the intermediate portion 1b of the shaft 1, a fixed ring 11 fixedly attached to the flange 8c, and a support body between the support body 10 and the fixed ring 11. 10 to spring 1
It consists of a push ring 13 and an abutment ring 14, which are pressed against the fixed ring 11 by a ring 2. The support 10 is a ring having a U-shaped cross section as shown, and is attached to the shaft 1 with a fixing bolt 15 so as to rotate together with the shaft 1. The push ring 13 is for pushing the abutment ring 14, and strongly presses the tip of the abutment ring 14 against the surface of the fixed ring 11. Sealing is achieved by the contact between the tip of the contact ring 14 and the surface of the fixed ring 11.
Naturally, the contact ring 14 rotates with its tip in contact with the surface of the fixed ring 11. This contact ring 14 is made of carbon. An O-ring is installed between the contact ring 14 and the push ring 13 to prevent fluid from entering through the surface of the shaft 1.

As described above, the conventional sealing member is configured to press the contact ring 14 against the fixed ring 11 with the spring 12, so it requires many parts, and
The space 9 for accommodating these must be enlarged. Therefore, the flange 8c is attached to the case 8.
had to be formed at a distance from the side surface 8a, and the overall size had to be large.

In addition, since there are a large number of parts and they are assembled in a complicated manner, it becomes difficult to remove the seal member due to wear of the abutment ring or the like. Furthermore, if the fluid is highly viscous, such as mayonnaise, the fluid adheres to various parts of the sealing member, and its removal is time-consuming.

The object of the present invention is to provide a sealing member for a pump that eliminates these drawbacks. More specifically, it has a simple structure, is easy to disassemble and assemble, has few parts that come into contact with the fluid in the pump, and can be easily removed after disassembling even highly viscous fluid and removing the sealing member. It is an object of the present invention to provide a sealing member that is easy to seal.

Therefore, the present invention provides a seal pedestal that can be detachably attached to the outer surface of the shaft tip, the outer surface of the seal pedestal has a plurality of stepped surfaces, and an annular projection is formed at the tip, and the case A flexible sealing material is inserted between the inner surface of the hole and the outer surface of one of the seal pedestals.

Since a flexible sealing material is inserted into the outer surface of the seal pedestal and the inner surface of the hole in the case, the sealing material provides a seal and no fluid leaks.
When removing the seal member of the present invention, the whole can be taken out by simply hooking a suitable object onto the annular protrusion of the seal holder and pulling it out. In addition, since the seal pedestal only needs to have a part to which the sealing material is attached and a part provided with an annular projection at the tip, the length of the seal pedestal can be shortened and the whole can be made smaller. . Further, since the only parts are the seal pedestal and the sealing material, the number of parts is small, and the number of parts that come into contact with the fluid is also minimized.

The illustrated embodiment will be described below. Shaft 16
(Fig. 3) is rotatably attached to the shaft case 18 with bearings 17, 17, sealed with a shaft seal 19, and the rotor is detachably attached to the tip of the shaft 16, as in the conventional case. be. By using the sealing member of this embodiment, the tip of the shaft case 18 can be attached directly to the side surface 21a of the case 21 as shown in the drawing. The shaft 16 has a tip end 16a which is the thinnest, and an intermediate portion 16c having an intermediate thickness is formed between the shaft 16 and the mounting portions 16b of the bearings 17, 17. This intermediate portion 16c may have a very narrow width as shown in the figure. A seal holder 23 is attached to the tip end 16a of the shaft 16 near the middle portion 16c. The seal pedestal 23 has an inner diameter equal to the outer diameter of the tip 16a of the shaft 16, and is formed into a cylindrical shape with steps of different heights formed on the outer surface. As shown in FIG.
The outer diameter is the largest and the next sealing material holding portion 23c
Steps are provided so that the next innermost pull-out portion 23d has the smallest diameter.
An annular protrusion 23e is formed at the tip of the drawer portion 23d for hooking the seal holder 23 when the seal holder 23 is pulled out. The seal holder 23 is attached to the shaft 16 by fitting a claw 23a provided on an edge 23b into an intermediate portion 16c of the shaft 16. case 21
The inner diameter of the hole provided in the side surface 21a for inserting the shaft 16 is slightly larger than the outer diameter of the edge 23b. A notch is formed in the inner side of the case on the inner surface of this hole, and this notch and the sealing material holding portion 23c of the seal holder 23 form a space having a U-shaped cross section. A packing 24 and a back-up spring 2 as a flexible sealing material in this space.
Insert and attach 5. The packing 24 is made of urethane rubber and has a ring shape, and has a notch 2 on one side.
4a. This packing 24 is commercially available and can be used as is.
The back up spring 25 is for reinforcing the packing 24, and is made of Teflon and formed into a ring shape. Grooves are provided at appropriate locations on the inner surface of the seal pedestal 23, and O-rings 26 are attached thereto to prevent fluid from leaking across the surface of the shaft 16.

In the figure, 27 is an eccentric ring attached eccentrically to move the blade up and down in accordance with the rotation of the shaft 16, and 28 is a part processed with ceramic to reinforce the inner surface of the case 21.

In this way, if the gasket 24 is provided between the inner surface of the hole through which the shaft 16 passes and the seal pedestal 23 attached to the surface of the shaft 16, the fluid inside the pump will be transferred to the outside by the gasket 24. Prevented from leaking. The gasket 24 has a groove with a notch 24a on its surface, and both ends of this groove are pressed by the fluid against the surface of the hole and the surface of the seal pedestal 23, further preventing fluid from leaking. do. Further, since the packing 24 and the back-up spring 25 are not particularly fixed, they do not interfere with the rotation of the seal holder 23, that is, the rotation of the shaft 16.

The seal member having the above structure is removed as follows. First, remove the side surface 21b of the case 21, pull out the rotor 20, and then
All you have to do is hook an appropriate object onto the annular protrusion 23e at the tip of 3 and pull it out. There is a step on the outer surface of the seal pedestal 23, and the seal 24 and back-up spring 25 are located at the second height of the surface of the seal pedestal 23, and the outer side is the highest, so when the seal pedestal 23 is pulled out, They can be taken out at the same time.
To attach the seal member, insert the seal holder 23 from the tip of the shaft, push it in, fit the claw 23a into the middle 16c of the shaft 16, and insert the back-up spring 25 into the space between the seal holding part 23d and the surface of the hole. All you have to do is insert the gasket 24.

As described above, according to the present invention, the seal member has a cylindrical shape with a step on the outer surface and is removably attached to the tip of the shaft, and the surface of the seal holder and the inner surface of the case hole are connected to each other. Since only a flexible gasket is inserted between them, the structure is extremely simple and can be made inexpensive.

In addition, as mentioned above, only the seal pedestal and packing are used, and no grease or the like is used, so there is no risk of impurities getting mixed into the fluid, and it can be used not only for food production but also for shafts of pumps used to transport cosmetics, pharmaceuticals, etc. It is ideal as a sealing member for sealing.

Furthermore, since there is no need to increase the length of the seal pedestal, there is no longer a need for a considerable length of space between the shaft bearing and the rotor as in conventional methods, and the tip of the shaft case can be attached directly to the side of the case. This allows the device to be made more compact. Furthermore, since the shaft can be shortened, the shaft strength of the rotor portion can be maintained.

Furthermore, the seal member of the present invention has a structure in which the seal material is placed on the surface of a seal holder that is detachably attached to the tip of the shaft, so the entire seal member can be removed simply by removing the seal holder. . In addition, since an annular projection is formed at the tip of this seal holder, the seal holder can be easily taken out by hooking it onto this projection and pulling it. Easy to install and remove.

Furthermore, unlike conventional methods, the seal member does not require a large space to be installed, so the area that comes into contact with the fluid inside the pump is minimized, and even if the fluid is viscous, the seal member can be removed and removed. After that, there is little need for fluid removal, making maintenance extremely simple. Furthermore, since there is no need for a large space as described above, there is less interference such as dry running due to air pockets when the pump is started.

[Brief explanation of the drawing]

Fig. 1 is a sectional view centered on the shaft of a conventional pump, Fig. 2 is a perspective view of the seal pedestal of the embodiment of the present invention, and Fig. 3 is a main part of the pump with the embodiment of the present invention installed. Cross-sectional view. 16: Shaft, 21: Case, 23: Seal pedestal, 24: Packing, 25: Backup spring.

Claims (1)

[Claims for Utility Model Registration] (1) The tip of the shaft is inserted into the interior through a hole provided on the side of the case, and the gap between the hole in the case and the outer surface of the shaft of a pump having a rotor at the tip of the shaft is sealed. A sealing member that is detachably attached to the outer surface of the shaft tip, the outer surface of which has a plurality of stepped surfaces, and a cylindrical seal pedestal having an annular projection at the tip; and the case. and a flexible sealing material inserted between the inner surface of the hole and the outer surface of one of the seal pedestals. (2) The sealing member according to Claim 1 of the Utility Model Registration Claim, wherein the outer surface of the seal pedestal is stepped with the outer surface being highest and gradually lowering toward the tip. (3) Utility model registration claim 1 or 2, in which the seal holder has three steps, and a flexible sealing material is arranged between the intermediate surface and the inner surface of the hole in the case. Seal member.