JPH05306687A - Rotary liquid pump - Google Patents

Abstract

PURPOSE:To prevent the immersion of a fine foreign substance between a key and a key groove to joint an impeller on a pump drive shaft and to prevent abrasion and gall of the aforementioned key and key groove. CONSTITUTION:In a rotary liquid pump with a tubular core material 32 made of a material higher in rigidity than an elastic material buried on a boss part 31 of an impeller 28 made of the elastic material and with a pump drive shaft and the tubular core material 32 rotationally integrally jointed with each other by a key by way of inserting the pump drive shaft into the tubular core material 32, seal parts 45, 46 positioned at both side parts of a key groove 35 provided on the circumferential surface of the tubular core material 32 and extending in the axial direction are formed integrally with the boss part 31 by the elastic material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary liquid pump using an impeller made of an elastic material.

[0002]

2. Description of the Related Art Like water pumps for outboard motors,
A rotary liquid pump that conveys liquid such as water containing foreign matter such as fine sand is formed of an elastic material such as rubber for the impeller that rotates in the pump chamber to prevent damage to the pump chamber and impeller due to foreign matter. There is.

The impeller has a boss portion (central portion).
A tubular core material made of a material such as synthetic resin or metal having higher rigidity than the elastic material is embedded in the pump core, and a pump drive shaft is inserted into the tubular core material so that the drive shaft and the tubular core material rotate integrally with a key. Be combined.

Generally, annular lips that are in close contact with the thrust surface of the pump chamber are formed on both end surfaces of the boss portion in the axial direction, and these annular lips are formed in the gap between the pump drive shaft and the tubular core material. It prevents foreign matter from entering and avoids wear and galling of the pump drive shaft and tubular core.

[0005]

By providing the above-mentioned annular lip on the boss portion of the impeller, it is possible to prevent fine foreign matter from entering between the pump drive shaft and the tubular core member to some extent. The purpose is fulfilled. However, it is impossible to prevent foreign matter from entering 100%, and a small amount of foreign matter enters between the key groove provided on the pump drive shaft and the tubular core member and the key, so that a long period of time cannot be obtained. There is still a risk of accumulation and accumulation of key grooves and keys, and galling of keys.

The present invention has been made to solve this problem, and prevents intrusion of fine foreign matter between the key for connecting the impeller to the pump drive shaft and the key groove.
An object of the present invention is to provide a rotary liquid pump capable of preventing wear and galling of the key and the key groove.

[0007]

In order to achieve the above object, a rotary liquid pump according to the present invention has a tubular core material made of a material having a higher rigidity than the elastic material, in a boss portion of an impeller made of an elastic material. Embedded in a rotary liquid pump in which the pump drive shaft is inserted into the tubular core member and the pump drive shaft and the tubular core member are rotationally integrated with a key,
It is characterized in that seal portions located on both sides of a key groove provided on the inner peripheral surface of the tubular core member and extending in the axial direction are integrally formed with the boss portion by the elastic material.

[0008]

With this structure, the seal portion is brought into close contact with the peripheral surface of the pump drive shaft, whereby the gap between the pump drive shaft and the tubular core member and the gap between the key groove and the key are separated from each other. Even if a minute foreign substance enters into the gap between the pump drive shaft and the tubular core member by being liquid-tightly sealed, this foreign substance is prevented from entering the gap between the key groove and the key.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a left side view of an outboard motor to which the present invention is applied. The outboard motor 1 is attached to a transom 4 of a hull 3 by a clamp bracket 2, and an engine 7 is installed in a top cowling 5 and a bottom cowling 6.
However, it is mounted vertically so that a crankshaft (not shown) is upright.

The drive shaft 8 connected to the crankshaft has an upper case 9 and a lower case 10.
It extends in the vertical direction and is orthogonal to a propeller shaft 12 horizontally supported in the lower case 10 via a forward / reverse switching device 13. A propeller 14 is rotatably integrated with the rear end of the propeller shaft 12.
4 is driven by the output of the engine 7 to give propulsive force to the hull 3.

A water pump 15 for supplying cooling water into the engine 7 is installed, for example, on the upper surface of the lower case 10, and the drive shaft 8 serves as a pump drive shaft. The water pump 15 is the rotary liquid pump according to the present invention.

For example, a cooling water intake 16 is provided on the side surface of the lower case 10, and an intake passage 17 connecting the cooling water intake 16 to the water pump 15 is provided in the lower case 10. In addition, a discharge passage 18 that connects the water pump 15 to the engine 7 is provided in the upper case 9, and a discharge passage 19 extends from the engine 7 to a water detection hole 20 provided in the bottom cowling 6. Connected.

The engine 7 operates to drive the drive shaft 8.
When is rotated, the water pump 15 sucks in the cooling water such as sea water, river water, or lake water as the cooling water from the cooling water inlet 16, and sends it to the engine 7 from the discharge passage 18. The cooling water that has cooled the engine 7 passes through the discharge passage 19 and the water detection hole 2
It is discharged from 0 to the outside.

FIG. 3 is a vertical sectional view of the water pump 15, and FIG. 4 is a view of the water pump 15 taken along the line IV-IV in FIG.
FIG. The pump housing 22 of the water pump 15 is fixed to the upper surface of the lower case 10 via an under panel 23, and the pump housing 22 and the under panel 23 form a cylindrical pump chamber 24.

In the pump housing 22, the discharge passage 1 is provided.
8 is formed, and an outlet 26 that connects the discharge hole 25 and the pump chamber 24 is formed. In addition, a crescent-shaped inlet 27 is provided in the under panel 23 to connect the pump chamber 24 to the suction passage 17.

Drive shaft 8 serving as a pump drive shaft
Is eccentric with respect to the center of the pump chamber 24 and passes through,
An impeller 28 is attached to the drive shaft 8 so as to rotate together. 5 is a plan view of the impeller 28, FIG. 6 is a sectional view of the impeller 28 taken along line VI-VI of FIG. 5, and FIG. 1 is a perspective sectional view of the impeller 28.

In the impeller 28, a plurality of blade portions 30 ... And a boss portion 31 are integrally formed of an elastic material such as rubber, and the boss portion 31 is made of a material having a higher rigidity than the elastic material (for example, a hard material). A tubular core material 32 made of synthetic resin or metal is embedded. This tubular core 3
2 is fixed to the boss portion 31, and both end surfaces thereof are covered with inner flanges 33 and 34 formed on the boss portion 31.

The inner diameter of the tubular core member 32 is such that the drive shaft 8 can be inserted smoothly and without play. On the other hand, the inner diameters of the inner flanges 33 and 34 are the same as those of the tubular core material 3.
It is slightly smaller than the inner diameter of 2 and is fitted to the peripheral surface of the drive shaft 8 with an appropriate tightening margin.

A key groove 35 is provided on the inner peripheral surface of the tubular core member 32, and between the key groove 35 and the key groove 36 provided on the drive shaft 8 as shown in FIGS. 3 and 6. A half-moon shaped key 37 is fitted to the drive shaft 8, and the impeller 28 is attached to the drive shaft 8 so as to rotate together. It should be noted that the inner flange 33 has a notch 38 continuous with one end of the key groove 35.
The impeller 28 is inserted into the drive shaft 8 in which the key 37 is fitted in the key groove 36 in advance from the cutout portion 38 side.

Annular lips 40 and 41 are integrally formed on the inner flanges 33 and 34, respectively, and a sealing 42 that is flush with the lip 40 is provided around the notch 38. Further, thrust seal surfaces 43, ..., 44 ... Are provided on the upper and lower edges of each wing portion 30 ... so as to be flush with the lips 40, 41. The lips 40, 41, the sealing 42, and the thrust seal surface. 43
.., 44 contact the thrust surfaces 24a, 24b of the pump chamber 24 with an appropriate pressure when the impeller 28 is assembled in the pump chamber 24. Further, the tips of the blades 30 ... Abut on the inner peripheral surface 24c of the pump chamber 24.

At both sides of the key groove 35 provided on the inner peripheral surface of the tubular core member 32, a seal portion 45 extending in the axial direction,
46 is formed in a strip shape. These seal parts 45,
46, the both ends of the inner flange 34, 3 respectively.
Connected to 4. That is, the seal portions 45 and 46 are integrally formed with the boss portion 31 by the elastic material forming the boss portion 31, and are fixed to the tubular core material 32. The seal portions 45 and 46 are formed by attaching the drive shaft 8 to the tubular core member 32.
When it is inserted, the drive shaft 8 comes into close contact with the peripheral surface of the drive shaft 8 with an appropriate pressure. Seal part 45,
Although the cross-sectional shape of 46 is a substantially rectangular cross-section in the present embodiment, it is not limited to this shape, and for example, a kamaboko-shaped cross-section as shown in FIG. 7A or a triangular cross-section as shown in FIG. 7B. Also good.

The water pump 1 configured as described above
5, when the impeller 28 is driven by the drive shaft 8 to rotate, the volume of the transfer chambers 47 ... (See FIG. 4) formed between the blade portions 30 of the impeller 28 changes due to the curvature of the blade portions 30. The volume of the transfer chambers 47 ... Expands along the inlets 27 and decreases along the outlets 26, so that the cooling water is transferred from the inlets 27 to the transfer chambers 47 ...
Are sequentially taken in and are pushed out to the outlet 26 and sent to the engine 7.

When fine foreign matters such as sand are mixed in the cooling water taken in from the inlet 27, these foreign matters slide on the thrust surfaces 24a and 24b of the pump chamber 24, and the drive shaft 8 and the lips 40 and 41. With the inner flanges 33 and 34 that are in close contact with the peripheral surface of the drive shaft 8, it is possible to prevent the drive shaft 8 and the tubular core material 32 from entering the gap, and to prevent problems such as wear and galling of the drive shaft 8 and the tubular core material 32. Avoided.

As shown in FIG. 8, the seal portions 45 and 46 fixed to the inner peripheral surface of the tubular core member 32 are in close contact with the peripheral surface of the drive shaft 8, whereby the space between the drive shaft 8 and the tubular core member 32 is reduced. Gap A, keyways 35, 36 and key 3
A gap B between the gaps 7 is liquid-tightly sealed. For this reason,
Even if the lips 40, 41 and the inner flanges 33, 34 are not blocked, fine foreign matter that has entered the gap A is prevented from entering the gap B, and the gaps between the key grooves 35, 36 and the key 37 can be maintained for a long time. It will not accumulate over time. In this way, abrasion of the key grooves 35, 36 and the key 37 and galling of the key 37 are effectively prevented.

The seal portions 45 and 46 are the impeller 28.
Since it is simultaneously formed at the time of molding, there is no increase in cost associated with the formation of the seal portions 45 and 46.

In this embodiment, the rotary liquid pump according to the present invention has been described as a water pump for an outboard motor, but the present invention is not limited to this embodiment, and all impellers made of an elastic material are provided. It can be applied to liquid pumps.

[0028]

As described above, in the rotary liquid pump according to the present invention, the tubular core material made of a material having a higher rigidity than the elastic material is embedded in the boss portion of the impeller made of the elastic material, and the pump is In a rotary liquid pump in which a drive shaft is inserted through the tubular core member and the pump drive shaft and the tubular core member are rotationally integrated with a key, on both sides of a key groove provided on the inner peripheral surface of the tubular core member. The seal portion located and extending in the axial direction is integrally formed with the boss portion by the elastic material.

Therefore, the seal portion is in close contact with the peripheral surface of the pump drive shaft, whereby the gap between the pump drive shaft and the tubular core and the gap between the key groove and the key are liquid-tightly sealed. .. For this reason, even if a minute foreign matter enters the gap between the pump drive shaft and the tubular core material, this foreign matter is prevented from entering the gap between the key groove and the key, and the minute foreign matter is separated from the key groove and the key. It is prevented from accumulating in the gap, effectively preventing abrasion of the keyway and the key and galling of the key.

[Brief description of drawings]

FIG. 1 is a perspective sectional view of an impeller showing an embodiment of the present invention.

FIG. 2 is a left side view of an outboard motor to which a water pump serving as a rotary liquid pump according to the present invention is applied.

FIG. 3 is a vertical cross-sectional view of a water pump.

4 is a plan view of the water pump taken along the line IV-IV in FIG.

FIG. 5 is a plan view of the impeller.

6 is a sectional view of the impeller taken along line VI-VI in FIG.

FIG. 7A and FIG. 7B are views showing another example of the cross-sectional shape of the seal portion.

FIG. 8 is a cross-sectional view showing the action of the seal portion.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Outboard motor 8 Drive shaft serving as a pump drive shaft 15 Water pump serving as a rotary liquid pump according to the present invention 22 Pump housing 23 Under panel 24 Pump chamber 25 Discharge hole 26 Outlet 27 Inlet 28 Impeller 30 Wing portion 31 Boss portion 32 Tubular core material 33,34 Inner flange 35 Key groove 37 Key 40,41 Lip 45,46 Seal part

Claims (1)

[Claims] 1. A boss portion of an impeller made of an elastic material,
A rotary liquid pump in which a tubular core material made of a material having a rigidity higher than that of the elastic material is embedded, a pump drive shaft is inserted into the tubular core material, and the pump drive shaft and the tubular core material are rotationally and integrally coupled by a key. The rotary liquid pump according to claim 1, wherein seal portions located on both sides of a key groove provided on the inner peripheral surface of the tubular core member and extending in the axial direction are integrally formed with the boss portion by the elastic material. ..