JPS6240145Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a bellows-type pump having a bellows that reciprocates via a connecting rod in response to the operation of a crank.

A bellows-type pump generally has a structure in which one end of the connecting rod is directly connected to the retaining plate of the bellows, and reciprocating motion is transmitted to the bellows in response to crank operation, thereby changing the volume of the pump chamber. It is designed to supply fluid. In such a structure, in addition to the force applied to the bellows in a direction perpendicular to the retaining plate of the bellows, that is, in the direction of the reciprocating motion of the bellows, there is also a rocking force that tilts the retaining plate due to the eccentric movement of the crank, and a retaining force. The torsional force that rotates the plate acts, and these rocking forces and torsional forces act as an unreasonable force on the bellows, resulting in cracks and breakage of the bellows and deteriorating the durability of the bellows. .

Therefore, in order to eliminate the rocking force, a method has already been proposed in which the connecting rod is divided into parts, a rotation joint is provided in the middle, and the rod portion on the bellows side is guided by a linear guide to prevent rocking. has been done.

However, a structure that eliminates twisting force has not yet been found, and in this respect, a new proposal is expected.

Therefore, the purpose of the present invention is to eliminate the transmission of torsional force to the bellows from the crank side, to ensure that the force of linear reciprocating motion is transmitted to the bellows from the connecting rod, and to have a simple structure and easy assembly. An object of the present invention is to provide a device for easily preventing bellows from twisting in a bellows type pump.

In order to achieve the above object, in the present invention, the connecting rod is composed of a crank-side rod member and a bellows-side rod member, a bearing support member is integrally provided at one end of both rod members, and a bearing support member is integrally provided at one end of both rod members. We have proposed a configuration in which a pair of thrust bearings are supported, which are arranged opposite to each other so that the bearing support members are sandwiched between them.

With the above basic configuration of the present invention, linear axial reciprocating power is directly transmitted from the crank side rod member to the bellows side rod member via a pair of thrust bearings, so both rod members are integrally connected. There is no difference in the structure from the previous one, and the torsional force transmitted from the crank to the crank-side rod member is
Since the other bellows-side rod portion is freely supported in the rotational direction by the pair of bearings, no transmission is transmitted to the bellows-side rod portion. Therefore, the bellows is completely freed from unreasonable force due to twisting force, and the excellent effects conventionally expected can be obtained.

Embodiments of the present invention shown in the drawings will be described below.

The bellows-type pump shown in FIG. 1 allows the pump supply fluid to flow from an inlet 1 through a valve 2 into a pump chamber 3, and through the reciprocating motion of a bellows 4, from the pump chamber 3 through a valve 2 to an outlet 5. It is designed to discharge quantitatively in sequence. The bellows 4 itself has a conventional structure made of metal or hard plastic such as Teflon (trade name), and is fixed at one end to a pump frame 6 and to a bellows retaining plate 7 at the other end. or,
An auxiliary bellows 8 is arranged on the opposite side of the bellows 4 with a retaining plate 7 in between to balance the expansion and contraction of the bellows 4, and each end thereof is fixed to the retaining plate 7 and the pump frame 6.

On the other hand, as schematically shown in FIG. 1, the crank 9 that applies reciprocating force to the bellows 4 is driven to continuously rotate in the direction of the arrow by, for example, a motor, and this power is transmitted to the bellows 4 via a connecting rod 10. be done.

In the figure, the connecting rod 10 is roughly divided into two parts, one end of which is attached and fixed to the retaining plate 7 of the bellows 4 at a substantially right angle to constitute a bellows-side rod member 11. The other end is connected to the crank 9 to constitute a crank-side rod member 12. A twist prevention device according to the present invention is provided between the other ends of both rod members 11 and 12.

The crank rod member 12 further comprises a crank rod portion 12a which is directly connected to the crank 9, and a rod portion 12b which is connected to the rod via a rotary joint 13 and is guided by a linear guide 14 so as to move only in the direction of the axis X-X, which corresponds to the direction of the reciprocating motion of the bellows.
Therefore, because of the presence of the rotary joint 13, the swinging force is no longer transmitted from the crank side to the rod portion 12b, but the torsional force is not removed.
A torsional force acts around X.

Here, at the end of the bellows-side rod member 11, a pair of ring-shaped thrust bearings 15 are provided around the end of the bellows-side rod member 11, spaced apart along the bearing XX.
16, and the outer race 15a of one of the bearings 15 is integrally formed with the rod member.
1a is press-fitted into the stepped portion 11b, and the other bearing 16
The outer race 16a is press-fitted into the stepped portion 17a of the retainer ring 17 inserted into the end of the rod member.
On the other hand, the end of the crank-side rod member 12 is configured as a large-diameter cylinder portion 12c with an open end, and a flange 12d extending outward in the radial direction is integrally provided on the open end edge of the cylinder portion 12c. As shown in FIG. 2, a ring-shaped bearing support member 18 is integrally fixed to the flange 12d with bolts 19 or the like. The bearing support member 18 is made of a rigid metal disk extending in the radial direction with respect to the axis X-X, and has stepped portions on both sides of its inner peripheral edge to support the inner races 15b and 16b of the bearings 15 and 16. is formed. Therefore, the member 18 has both bearings 15 and 16.
It appears to be held between the two.

With the member 18 being held between the pair of bearings 15 and 16 in this way, the member 18 is held and fixed by screwing the tightening fixing nut 20 into the threaded bolt portion 11b formed at the end of the bellows side rod member 11. be done. Therefore, the bellows side rod member 11
can move integrally with the crank-side rod member 12 in both directions along the axis X--X. On the other hand, regarding the direction of rotation around the bearing XX, that is, the torsion, both rod members 1
Between 1 and 12, it is completely free. In other words, the rod member 12 is closer to the crank than the crank 9.
When a torsional force is applied to the bearing support member 18, the bearing support member 18 rotates together with the inner races 15b and 16b of both bearings 15 and 16, and the outer races 15a and 16a of both bearings rotate.
can remain stationary in the rotational direction together with the bellows-side rod member 11. Of course, there is rolling resistance of the balls in each bearing, but the rotational force transmitted by this is almost negligible, and the bellows 4 is protected from the torsional force from the crank 9. virtually completely liberated.

In addition, in the configuration of the present invention, as can be seen in FIG. 2, the bellows side rod member 11 and the crank side rod member Part 1
2. Since the pair of bearings 15, 16 and the bearing support member 18 are arranged concentrically, only the force along the bearings XX is transmitted to the bellows.

Further, since the end of the bellows-side rod member 11 extends into the cylinder portion 12c of the other rod member 12, the length in the axial direction is shortened, and the entire device can be made more compact.

Further, in assembling, first, the pair of bearings 15, 16 and the bearing support member 18 are held in the bellows-side rod member 11, and the nut 20 is tightened to fix the unit. Since the bearing support member 18 can be attached to the flange 12d of the crank-side rod member 12 while being inserted into the shaft, the attachment work can be done easily. Moreover, in the case of removal, it can be similarly easily done by performing the reverse operation.

In the embodiment, the pair of bearings 15 and 16 are supported by the bellows-side rod member 11, and the bearing support member is fixed to the other rod member 12, but this is reversed and the bellows-side rod member 11 is A cylinder part with an enlarged diameter is provided at the end, and a bearing support member is fixed to the crank side rod member 12.
A configuration in which a pair of thrust bearings are disposed at both sides is easy in terms of design, and the present invention can adopt either configuration.

As described above, according to the present invention, the torsional force acting on the bellows from the crank side is substantially eliminated by the bellows twist prevention device provided at the intermediate portion of the connecting rod, so the durability of the bellows is greatly improved. Various practical effects can be obtained, such as extending the life of the pump and reducing the frequency of maintenance inspections and parts replacement.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway vertical cross-sectional view of a bellows-type pump equipped with a twist prevention device according to the present invention, and FIG. 2 is a cross-sectional view taken along the line -- in FIG. 1. 4... Bellows, 9... Crank, 11... Bellows side rod member, 12... Crank side rod member, 15, 16... Thrust bearing, 18... Bearing support member.

Claims (1)

[Claims for Utility Model Registration] (1) A bellows-type pump equipped with a bellows that reciprocates via a connecting rod in response to crank operation, a crank-side rod member having the connecting rod attached to the crank side; A bellows-side rod member is attached to the bellows side, and a bearing support member is integrally provided at the end of one rod member along the radial direction with respect to the axial direction of the connecting rod, and the end of the other rod member is A device for preventing twisting of a bellows in a bellows type pump, wherein a pair of thrust bearings facing each other along the axial direction of a connecting rod are disposed around the shaft, and the bearing support member is supported so as to be sandwiched between these bearings. (2) One of the rod members is a bellows-side rod member, and one end of the rod member is fixed to a retaining plate of the bellows, and the other end is a screw that supports the pair of thrust bearings arranged around the rod member. A bellows twist prevention device according to claim 1, wherein a bolt portion is formed and a nut is screwed into the bolt portion. (3) A cylinder portion with an open end is provided at one end of the other rod member, the bearing support member is fixed to the open end edge of the cylinder portion, and the end of the one rod member is disposed within the cylinder portion. A bellows twist prevention device according to claim 1 or 2 of the utility model registration claim, in which the bellows is extended.