JPS5930914B2 - bicycle air pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bicycle air pump for inflating bicycle tires.

Conventional bicycle air pumps generally have a single valve that moves back and forth inside a cylinder, and when the valve moves forward, the pressurized chamber inside the cylinder becomes under positive pressure, so the valve expands and comes into close contact with the side of the cylinder. The air will be compressed and injected into the tube.

When the valve moves back, the pressure chamber becomes negative pressure, so the valve contracts, and air flows through the gap between the valve and the cylinder, replenishing the pressure chamber with air.

Here, it is desirable that the number of times the air pump is activated until the inside of the tube reaches a predetermined air pressure is as small as possible.

For this purpose, it is sufficient to lengthen the air compression stroke and increase the inner diameter of the cylinder.

However, air pumps are often used by children, and it is not desirable to lengthen the compression stroke.

Furthermore, as the inner diameter of the cylinder increases, the cross-sectional area of the cylinder also increases, and since the required air pressure per unit area remains the same, the force for operating the pump increases.

In other words, it becomes a heavy air pump that requires a lot of power.

The present invention has been made from the above-mentioned viewpoint, and has a structure in which the amount of air injected can be increased with the same operating force as the conventional one, and conversely, the operating force can be reduced with the same amount of air as the conventional one. The purpose is to provide a pump.

The invention will now be described in detail with reference to the drawings.

In the figure, numeral 1 is a hollow cylindrical outer cylinder that becomes the cylinder of a bicycle air pump.

In the present invention, the lid 2 is fixed to one end of the outer cylinder 1, the lid 2 is provided with a ventilation hole 3 for communicating with the outside air, and the base of the core frame 4 located at the center of the outer cylinder 1 is placed in the center of the lid 2. The core frame 4 is implanted by screwing into the provided screw hole, and an annular lip valve 5 having a lip directed inward of the outer cylinder 1 is provided on the inner periphery of the other end of the outer cylinder 1.

Note that 6 is a plug fixed to the outer cylinder 1 on the outside of the valve 5 to prevent the valve 5 from being removed, and 7 is a resilient cushioning material provided inside the outer cylinder 1 for cushioning on the inside of the valve 5. 8 is a retaining ring of this buffer material 7 and is caulked to the outer cylinder 1.

In addition, an inner cylinder 9 that slidably fits into the lip valve 5 is inserted into the outer cylinder 1, and an annular lip valve 10 whose lip that makes sliding contact with the outer cylinder 1 and the core frame 4 is directed inward is removed. Inner cylinder 9 inside cylinder 1
A vent hole 11 is provided at the end of the lip valve 10 and penetrates through the inner cylinder wall near the lip valve 10.

Reference numeral 12 denotes a retaining ring fitted to the inner cylinder 9 in order to fix the lip valve 10 to the inner cylinder 9.

In addition, an adapter 14 having a ventilation hole 13 that communicates the air valve of a bicycle tire (not shown) with the inside of the inner cylinder 9 is attached to the outer end of the inner cylinder 9, and a hollow cylindrical adapter 14 that can enclose the outer cylinder 1 is attached to the outer end of the inner cylinder 9. A ring-shaped gasket 16 is attached to the grip 15 and is provided at the open end of the ventilation hole 13.

17 is a middle seat inserted into the handle 15 to prevent the grip 15 from rattling against the inner cylinder 9; 18 is a coil spring interposed between the grip 15 and the cylinder 9; It serves as a buffer when the air pump is pushed all the way into the grip 15, and as a self-retainer when the air pump is mounted on a bicycle body.

Further, a disc-shaped lip valve 19 is provided at the end of the core frame 4, the lip of which makes sliding contact with the inner wall of the inner cylinder 9 and is oriented outward.

20 is a dog washer for holding this lip valve 19;
1 is a small washer for holding the lip valve 19, 22
is the tightening nut.

Note that a check valve 3a is installed in the vent hole 3 of the lid 2 as shown in FIG.
may be provided.

Next, the operation of the air pump of the present invention constructed as described above will be explained.

To inflate a bicycle tire with this air pump, hold the outer end of the outer tube 1 with one hand, hold the adapter 14 with the other hand, and press the gasket 16 against the air valve of the tire.

When the outer cylinder 1 is pulled in the direction of arrow A as shown in FIG. The volume of both the air quality 24 sandwiched between the valve 10 and the air quality 23 decreases.
and air quality 24 are both pressurized.

Since there is an air vent 11 in the inner cylinder 9 near the valve 10, the pressurized air in the air chamber 24 passes through the vent 11 and flows into the air chamber 23 as shown by the small arrow in the figure. The liquid then flows into the pressurizing chamber 25 by compressing the outer peripheral lip of the valve 19 .

In other words, by pulling the outer cylinder 1 in the direction of arrow A, the pressurizing chamber 2
Although the volume of air chamber 5 increases, the combined volume of air chambers 23 and 24 decreases more, so the air in pressurizing chamber 25 is pressurized.

That is, if the volume of the pressurizing chamber 25 of the pump of the present invention is the same as that of the conventional bicycle air pump, the pump of the present invention will be filled with extra pressurized air, and will have a larger volume than the conventional product. The pressurizing chamber 25 is filled with air.

Note that the degree to which the pressurizing chamber 25 is pressurized can be set as desired by selecting the diameters of the inner cylinder 9, outer cylinder 1, and core frame 4.

Next, as shown in Fig. 3, when the outer cylinder 1 is pushed in the direction of arrow B,
As the air chambers 23 and 24 increase in volume, they become negative pressure, and the lips of the valves 5 and 10 are opened as shown by the small broken arrows, and air flows into the air chambers 23 and 24, and at the same time, the air enters the pressurized chamber 25.
The air already pressurized within is further pressurized by the movement of valve 19.

If the pressure inside the pressurizing chamber 25 becomes higher than the total pressure of the pressure required to push open the tire's air valve (not shown) and the air pressure inside the tire tube (not shown), the pressure inside the adapter 14 becomes higher. Air is injected into the tire tube through the ventilation hole 13 of the tire.

Note that when the air pressure inside the tire tube is almost zero, only the pressure that pushes the air valve of the tube open will inject air into the tube even with the excess pressure when the pump is pulled. is injected into the tube by pressurization during the pushing operation.

As described above, the air pump of the present invention is different from conventional air pumps in that it is pressurized even during pulling operation, but here, the inner diameter of the inner cylinder 9 of the pump of the present invention is the same as that of the conventional air pump. Assuming that the inner diameter of the cylinder of the chamber is the same (assuming that the conditions for valve stroke transmission are also the same), the amount of air filled in the inner cylinder 9 that is pressurized during the pump operation of the present invention is the same as that of the conventional pump. - More air can be injected into the tube in a reciprocating operation.

Moreover, when the air pressure inside the inner cylinder 9 increases and air is injected into the tube, the cross-sectional area inside the inner cylinder 9 is the same as that of the conventional product, so the operating force at this time is also the same as that of the conventional product. Become.

In other words, when air is injected into the tube that requires the most force, the operating force is the same as that of a conventional air pump.

On the other hand, if the amount of air injected during the reciprocating operation is made to be the same as the conventional product, the inner diameter of the inner cylinder 9 will be made smaller to account for the extra amount of air that will be filled by the amount of air that is pressurized during the pulling operation. can do.

Therefore, since the cross-sectional area of the inner cylinder 9 becomes small, it is possible to reduce the operating force when injecting air while maintaining the same amount of air as in the conventional case.

This is particularly effective in bicycle frame pumps.

When injecting air, one hand holds the adapter 14 and pushes it onto the air valve on the wheel, while the other hand performs the pumping action, so the air valve, which is attached to a rubber tube, tends to wobble.

In addition, the wheels are also unstable, so in the case of conventional frame pumps, when operating with force in the hand, the adapter 14
The hand holding the valve was shaky and air often leaked from between the gasket 16 and the air valve.

From this point of view, if the operating force is lightened to reduce the wobbling of the hand holding down the adapter 14, air leakage during operation will be reduced, making profit work easier.

Of course, this feature can also be utilized with a foot-operated air pump, but in the case of a foot-operated pump, it is preferable to increase the amount of air a little.

In addition, as shown in FIG. 4, a check valve 3a is installed in the vent hole 3 of the lid 2.
If a check valve is provided so that the vent hole 3 is blocked when the outer cylinder 1 is pushed, outside air would be introduced into the air chambers 23 and 24 due to the negative pressure caused by the increased volume when there was no check valve. However, since the air in the air quality 26 is pressurized by the effect of the check valve 3a, the efficiency of filling air into the air quality 23 and 24 can be further improved.

As mentioned above, the air pump of the present invention can inject a larger amount of air than conventional pumps if the operating force is the same as that of a conventional pump, and conversely, if the injected air amount is the same as a conventional pump, the operating force can be reduced. It has the excellent effect of being able to

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of the air pump of the present invention, Fig. 2 is a sectional view for explaining the air flow during the pulling operation, and Fig. 3 is a longitudinal sectional view of the air pump of the present invention.
The figure is a sectional view for explaining the flow of air during the pushing operation, and FIG. 4 is a partial sectional view showing another embodiment. 1... Outer cylinder, 2... Lid, 3...
・Vent hole, 3a... Check valve, 4... Core frame, 5... Valve, 6... Plug, 7...
...Buffer material, 8...Retaining ring, 9...Inner cylinder, 10...Valve, 11...Vent hole, 12
...Retaining ring, 13...Vent hole, 14.
...Adapter, 15...Grip, 16.
...Patsukin, 17...Nakaza, 18...
...Coil spring, 19...Valve, 20...
...Dog washer, 21...Small washer, 22...
...Tightening nuts, 23, 24, 25, 26...
・Air chamber.

Claims (1)

[Scope of Claims] 1. A core frame located at the center of the outer cylinder is installed in a lid having a ventilation hole fixed to one end of the outer cylinder, and an annular valve is provided on the inner periphery of the other end of the outer cylinder. An inner cylinder that slidably fits into the valve is inserted into the outer cylinder, an annular valve that makes sliding contact with the outer cylinder and the core frame is provided at the end of the inner cylinder inside the outer cylinder, and an inner cylinder near this valve is inserted into the outer cylinder. An adapter having a ventilation hole penetrating the wall and communicating between the air valve of the tire and the inside of the inner cylinder is fixed to the outer end of the inner cylinder, and the valve is in contact with the inner wall of the inner cylinder at the end of the core frame. A bicycle air pump equipped with 2. The bicycle air pump according to claim 1, wherein a check valve is provided in the vent hole of the lid fixed to one end of the outer cylinder.