JPH05302573A - Bellows type compressing device - Google Patents

Abstract

PURPOSE:To reduce the dead space while improving durability of bellows by providing the V-shaped bellows slidably in a cylinder, and fixing a rigid broad ring plate interposed respectively in a foldback part of these bellows. CONSTITUTION:A ring-shaped bellows 105 constitutes a V-shaped bellows by connecting many bellows 105a to 105g, and an inner side end part of the bellows 105a in the uppermost part is brought into contact with a fixed ring 103, provided in a lower surface of a piston 102, and fixed by a screw 109. Between each bellows, that is, in a foldback part, a rigid ring plate 110 of steel plate or the like for controlling displacement of the bellows is interposed and integrally fixed by a rivet 112, to also fix a piston ring 115, slid on a cylinder internal wall, to an outer side end part of each ring plate 110. In a part of connecting the inner side end part to each other of each bellows 105, that is, in also the foldback part, a ring plate 118 is interposed and integrally fixed by a rivet 120.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bellows type compression device applicable to pumps and blowers such as oilless vacuum pumps and oilless blowers, and liquid quantitative or viscous pumps.

[0002]

2. Description of the Related Art Currently, regarding oilless vacuum pumps, oilless blowers and liquid quantitative or viscous pumps,
For small models, diaphragm type and bellows type are used, but large-capacity large models have not yet been developed. For this large model, only screw type, vane type and piston type are used.

As described above, the diaphragm type and the bellows type cannot obtain high vacuum, high pressure and large capacity performance with the currently employed mechanism. That is, the diaphragm type is composed of one partition plate, and therefore, the pushing amount (stroke) thereof is limited. Further, since the diaphragm is an elastic body, the pressing force is limited with respect to the pressure receiving area, and high vacuum, high pressure, and large capacity performance cannot be exhibited. On the other hand, the same problem occurs when the diaphragm material is made of a metal plate, and metal fatigue occurs due to repeated reciprocation. For bellows type, high vacuum,
When trying to obtain high pressure and large capacity, the bellows diameter becomes large, and the inside is sucked toward the center during suction, causing deformation, and at the same time, it becomes difficult to reduce the internal volume during compression, and the gas volume during suction is reduced. There is a problem that the diffusion cannot occur and the performance as a vacuum pump cannot be exhibited. On the other hand, for screw type, plunger type, vane type, etc.,
At present, all of them still have many problems regarding the clearance of each part and the service life of the shaft sealing part.

Therefore, the present inventor has developed a bellows type compression device as described below. 4 and 5, 1 is a cylinder, 2 is a piston, 3 is a piston lot, 4 is a crank and a flywheel. Piston 2
Is composed of a piston head, a plurality of bellows, a plurality of discs and a plurality of rings. Ie 11, 1
2 and 13 are plural bellows (three in this embodiment), 1
4 and 15 are bellows 11 and 12 and bellows 12 and 1.
Discs 21, 22, 23, 24 provided between the discs 3 and 3 are rings for restraining the ends of the respective bellows, and 25 is a piston head. The disks 14 and 15 are provided with a through hole in the center. The piston head 25 has a connecting portion 26 with the piston rod 3 at the top, a plurality of piston rings 27 around the piston head 25, a projecting plate 28 protruding from the center of the lower surface, and an upper end of the bellows 11 around the lower surface. It abuts and presses it with the ring 21, and it is fixed to the piston head 25 with a screw 29. The ring 21 is thick on the outer peripheral side and thin on the inner peripheral side so that the bellows end is pressed against the lower surface of the piston head 25. Reference numeral 30 is a cushion ring fixed to the lower surface of the ring 21.

The disc 14 has a lower end of the bellows 11 and an upper end of the bellows 12 on the upper and lower surfaces of its peripheral end face.
In a state of being in contact with each other, the ring 22 is fitted into a ring-shaped circumferential groove 35, and the bellows 11, the disc 14 and the bellows 12 are integrally fixed to the ring 22 by screws 36. Reference numeral 37 denotes a protrusion plate fixed to the lower surface of the center of the disk 14, and the protrusion plate 37 has a ventilation hole 38 penetrating vertically. 39 is a cushion plate provided on the upper surface of the disc, 4
Reference numeral 0 is a cushion ring fixed to the lower surface of the ring 22. Reference numeral 41 is a piston ring provided on the outer peripheral surface of the ring 22. The disc 15 has the same structure as the disc 14 and is integrally fixed to the ring 23 together with the lower end of the bellows 12 and the upper end of the bellows 13. Similarly, a protrusion board 47 having a ventilation hole 48 is provided on the lower surface. The lower end of the bellows 13 is fixed to the bottom surface of the cylinder 1 by the ring 24.

The cylinder 1 is fitted so that the piston 2 can slide up and down, and a plurality of longitudinal grooves 50 are provided in a part of the inner wall thereof, and the ring 22 is provided in the groove 50. A stopper 51 protruding outward is fitted in the ring so that the vertically moving ring 22 stops at a predetermined position and does not rotate. As for the ring 23,
A similar stopper is provided, and a similar groove into which the stopper is fitted is provided at another position (not shown) on the inner wall of the cylinder 1, and the vertically moving ring 23 is stopped and rotated at a predetermined position as shown in FIG. It is configured not to. On the upper surface of the bottom portion 54 of the cylinder 1, a cushion ring 55
Is provided to absorb a shock when the projection disk 47 abuts upon compression. Reference numerals 56 and 57 are passages to check valves 60 and 61 provided on the outer surface of the bottom portion 54 of the cylinder 1.
In the check valves 60 and 61, 60a and 61a are springs, 60b and 61b are valves, 60c and 61c are seats, and 60d and 61d are conducting holes. In this way, in the cylinder 1 above and below the disks 14 and 15,
As shown in FIG. 4, inside the bellows 70,
71 and 72 are formed, and outer chambers 75, 76 and 77 are formed outside the bellows, respectively. The cylinder 1 is provided with flow holes 81, 82, 83 communicating with the outer chamber, and is connected to the flow passages respectively communicating with the heat exchangers 85 provided outside the cylinder 1.

The operation of this apparatus will now be described with reference to FIG.
When the piston 2 is pushed downward by the piston rod 3 by the power means (not shown) from the state shown in (4), the bellows 11, 12, 13 gradually bend. Interior room 7
The gas of 0, 71, 72 moves to the lower chamber through the ventilation holes 38, 48 of the projection plates 37, 47, respectively, and the gas of the inner chamber 72 is guided to the external device from the conduction path 57 via the check valve 61. Get burned. Further, the gas in the outer chambers 75, 76, 77 is introduced into the heat exchanger 85 through the flow holes 81, 82, 83, respectively, and heat generated by various frictions inside the cylinder is cooled to perform heat exchange. When the piston lot 3 reaches the lower limit, as shown in FIG. 5, the protrusion disc 47 is on the upper surface of the bottom portion 54 of the cylinder 1, the protrusion disc 37 is on the upper surface of the disc 15, and the protrusion disc 2
Each of the compressed bellows 13, 12, 11 is housed in a state in which it is regularly folded in the state shown in FIG. The lower end surface of each bellows is protected by hitting the cushion rings 55, 39, etc. provided on the upper surface of the bottom portion 54 of the cylinder 1 and the upper surface of the disk, respectively, and the cushion rings 30, 22, provided on the lower surfaces of the rings 23, 22, 21. Protected by 40 etc. When the piston 2 moves upward from the state shown in FIG. 5 again, gas flows from the check valve 60 into the inner chambers 7 in the bellows.
2, 71, 70, the state of FIG. 4 is restored, and thereafter, the same operation is repeated.

When the operation is repeated during the operation, positive and negative pressures are alternately generated in the gas, but when the pressure is low, the ventilating ports 81, 82, 83 of the cylinder 1 are connected to the external circulation passages. For example, the efficiency may be improved by guiding the inside of the crankcase and then recirculating the crankcase to prevent the obstacle due to the pressure difference. Further, in order to protect the bellows at the time of high pressure, vent holes 81, 8 provided in the cylinder as necessary are protected.
By closing the opening / closing mechanism of Nos. 2,83, the bellows inner chambers 70,7
The pressure difference between the outer chambers 1, 72 and the outer chambers 75, 76, 77 is offset and adjusted. However, with this device,
Although the above problems of the conventional device have been largely eliminated, the following problems have occurred. That is, when the piston is raised, the bellows 11, 12, 13 forming the inner chambers 71, 72, 73 in the cylinder do not become the state shown in FIG. Sometimes it is drawn to the center, and the problem that full function cannot be exhibited sometimes occurred. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a bellows type compression device that solves the above problems.

[0008]

According to the present invention, in accordance with the above object, a V-shaped bellows is provided slidably in a cylinder, and a rigid and wide ring plate is sandwiched and fixed to each folded portion of the bellows. By doing so, the above problem was solved.

Embodiments of the present invention will be described below in detail with reference to the drawings. In FIG. 1, 101 is a cylinder, 102 is a piston, and 105 is a ring-shaped bellows. The bellows 105 includes a large number of bellows 105a-
105g are connected to form a V-shaped bellows, and the inner end of the uppermost bellows 105a abuts on a fixed ring 103 provided on the lower surface of the piston 102, and the ring 108 is abutted on the fixed ring 103 by a screw 109. It is fixed. Rigid ring plates 110, such as steel plates, for controlling the displacement of the bellows are provided between the bellows, that is, at the folded portions thereof, and the tightening ring 111 is provided with bellows 105a, 105b. The upper and lower ends of the outer end portions of the two are abutted, respectively, and these are fixed by rivets 112. Reference numeral 115 denotes a piston ring that slides on the inner wall of the cylinder, and the outer end of the ring plate 110 is fixed to the piston ring 115. Reference numeral 116 is a plurality of ventilation holes provided around the ring plate 110. 11
Reference numeral 8 denotes another ring plate, which is provided at a connecting portion between the inner end portions of each bellows 105, that is, a folded portion, and tightening rings 119 are abutted on the upper and lower sides, respectively, and fixed by rivets 120. .. The other bellows are also constructed in the same manner as above.

The innermost end of the bellows 105h at the lowermost end is
Similar to the bellows 105a at the uppermost end, a ring 108 is brought into contact with and fixed to a fixing ring 121 at the bottom of the cylinder 101 with a screw 109. The bellows 105 is made of an elastic body such as rubber, is formed in a wavy shape in a radial cross section as shown in FIG. 2, and is formed so as to be able to expand and contract when vertically moved. The other structure is similar to that of the device described with reference to FIGS. 4 and 5, and thus the description thereof is omitted. When the device of this configuration is operated, the state shown in the right half of FIG. 1 is reached during compression, and the rigid ring plates 110, 118 and the like interposed between the bellows 105 maintain orderly spacing, and the bellows 105 Deformation can be prevented.
Further, the structure of the corrugated cross section of the bellows absorbs the elongation, and the durability of the bellows is improved.

FIG. 3 shows another embodiment in which bellows are arranged on both sides of a piston and two compression chambers are provided. That is, 201 is a cylinder, 202 is a piston that reciprocates in the cylinder 201, 203 is a piston rod, 250 is a first compression chamber, and 251 is a second compression chamber. The bellows and the like of the compression chamber 250 have the same structure as that of the embodiment shown in FIG. 1, and a spacer 240 is separately provided at the center of the piston 202. The bellows of the compression chamber 251 is provided with a bellows 206 having the same structure surrounding the piston rod 203, and further another bellows 207 is provided on the outer periphery thereof in the vicinity of the inner wall of the cylinder 201. That is, a bellows fixing ring 211 is provided on the side surface of the lid 210 of the cylinder 201, and another fixing ring 212 is provided on the outer side in the radial direction.
11, the bellows 206 is fixed to the fixing ring 212, and the end portion of the bellows 207 is fixed to the fixing ring 212 in the same manner as in the above embodiment. On the other hand, the second compression chamber 251 of the piston 202
The fixing ring 215 is also provided on the side surface, and another fixing ring 216 is provided on the outside thereof.
The other ends of 7 are similarly fixed. Bellows 20
The ring plate 22 is connected to the connecting portion 6 in the same manner as in the previous embodiment.
1 and 222 are interposed and fixed, and ring plates 226 and 227 are similarly interposed and fixed between the bellows 207. The outer peripheral end of the ring plate 226 is fixed to a piston ring 228 that slides on the inner wall of the cylinder.

Reference numeral 241 is a bellows 206 and a bellows 207.
It is a ring-shaped spacer provided on the side surface of the piston 202. The first compression chamber 250 has a cylinder side surface (or a cylinder bottom surface) facing the piston.
An exhaust port 230 and an intake port 231 are provided in the second compression chamber 251, and an exhaust port 232 and an intake port 23 are similarly provided in the lid 210 of the second compression chamber 251.
3 and 3 are provided. The exhaust port 230 and the intake port 233 are connected by a communication passage 235. Now piston 20
When 2 moves to the first compression chamber 250 side, the first compression chamber 250 is compressed and exhausted through the exhaust port 230, and the inner space of the bellows is occupied by the spacer 240. That is, there is no extra space inside the bellows. On the other hand, at the same time, the second compression chamber 251 expands, and suction is performed from the suction port 233. That is, it becomes a two-stage bellows pump. It should be noted that the space between the bellows is occupied by the spacer 241 when the second compression chamber 251 is compressed, and similarly there is no extra space. Also,
Even when used as a vacuum pump, since the piston rod portion is covered by the bellows 206, it is possible to prevent infiltration of gas, liquid, etc. from the bearing portion of the piston rod.

[0013]

According to the apparatus of the present invention, a wide and rigid ring plate is provided between the outermost and innermost peripheral portions of each bellows even if a high-pressure load is applied inside the bellows. Therefore, the bellows can be prevented from being reduced or deformed and the decrease in the internal volume can be prevented. In addition, by stacking the bellows in multiple stages, during compression, a large volume is occupied in the internal volume due to the thickness of the bellows itself, and the dead space is increased. Therefore, internal diffusion may occur during suction, but In the device, such a problem does not occur because a spacer is arranged between each bellows to reduce the space during compression as much as possible. Further, since the bellows has a wavy cross section in the radial direction, expansion and contraction of the bellows due to expansion and contraction of this portion can be absorbed, and the life of the bellows can be extended. When the bellows reciprocates by the piston and the bellows part is in a compressed state, a space is created at the rear part of the piston in the cylinder.However, since another bellows is provided in this space to form a two-stage type, a highly efficient compression is achieved. The device can be obtained. The two-stage bellows at the rear of the piston surrounds the piston rod and completely shuts off oily components from the bearing portion of the rod, so that it can be used as a dry pump.

[Brief description of drawings]

FIG. 1 is an explanatory view of a main part of an embodiment of a bellows type compression device according to the present invention.

FIG. 2 is an explanatory view showing a radial cross section of the bellows.

FIG. 3 is an explanatory view of a main part of another embodiment of the bellows type compression device according to the present invention.

FIG. 4 is a cross-sectional explanatory view of a bellows type compression device.

5 is an explanatory diagram of the device shown in FIG. 4 during compression.

[Explanation of symbols]

 101 cylinder 105 bellows 110, 118 ring plate

Claims (4)

[Claims] 1. A bellows type compression device characterized in that a V-shaped bellows is provided slidably in a cylinder, and a rigid and wide ring plate is sandwiched and fixed to each folded portion of the bellows. 2. The V-shaped bellows is provided on both sides of a piston that reciprocates in a cylinder, and another bellows surrounding the piston rod is provided in the bellows on the piston rod side. Bellows type compression device. 3. The V-shaped bellows has a wavy cross section in the radial direction.
Bellows type compression device described in. 4. The bellows type compression device according to claim 1, wherein an outer peripheral end portion of a ring plate fixed to the bellows is locked to a ring that slides on an inner wall of the cylinder.