Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
  • F04B39/10—Adaptations or arrangements of distribution members
  • F04B39/1053—Adaptations or arrangements of distribution members the members being Hoerbigen valves
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B37/00—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00
  • F04B37/10—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use
  • F04B37/14—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use to obtain high vacuum
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B37/00—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00
  • F04B37/10—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use
  • F04B37/14—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use to obtain high vacuum
  • F04B37/16—Means for nullifying unswept space
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
  • F04B39/0005—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00 adaptations of pistons
  • F04B39/0016—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00 adaptations of pistons with valve arranged in the piston
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
  • F04B39/10—Adaptations or arrangements of distribution members
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
  • F04B39/10—Adaptations or arrangements of distribution members
  • F04B39/102—Adaptations or arrangements of distribution members the members being disc valves
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
  • F04B39/10—Adaptations or arrangements of distribution members
  • F04B39/1046—Combination of in- and outlet valve

Definitions

• Piston battery pump with gas inlet and gas outlet
• the invention relates to a piston vacuum pump according to the preamble of patent claim 1.
• Single-stage and multi-stage piston vacuum pumps of this type are known from EU-A-85 687. Compared to comparable rotary piston vacuum pumps, they have proven to be inexpensive and wear-resistant and are therefore successful on the market.
• each of the cylinder / piston systems is equipped with a valve-controlled gas inlet and with a valve-controlled gas outlet.
• a piston-controlled gas inlet valve the gas inlet line opens into an annular groove in the cylinder wall, which is closed or released by the piston itself
• a pressure-controlled or piston-controlled gas outlet valve which are known about the entire valve face extending cylinder end.
• the present invention is based on the object of improving a piston vacuum pump of the type concerned here with regard to the gas entry.
• the gas inlet should be designed in such a way that no or only negligible negative pressures occur in the pumping chamber during the suction stroke of the piston.
• the realization of the advantages of the pump known from DE-A-196 34 517 - large-area inlet slots for gas exchange at low intake pressures and large-area and low-exhaust valves - should not be impaired. According to the invention, these objects are achieved by the characterizing features of the claims.
• a pressure-controlled inlet valve is provided in the piston vacuum pump according to the invention, which opens during the suction stroke, preferably in the first phase of the suction stroke.
• the pressure-controlled gas inlet valve can be the only inlet valve. However, if large inlet openings are to be provided at low intake pressures in order to achieve as complete a filling of the scooping space as possible before the start of the pressure stroke, it is expedient if the gas inlet according to the invention is present in addition to a second gas inlet, e.g. a gas inlet with a piston-controlled gas inlet valve, as is known from DE-A-196 34 517.
• FIGS. 1 to 11 Show it Figures 1 to 5 solutions in which a gas inlet valve is part of the cylinder head,
• Figures 10 and 11 further exemplary embodiments.
• All figures each show a partial section through a piston-cylinder system 1 of a piston vacuum pump which has one or more stages (be it that it has several piston-cylinder systems or that both piston ends have pump functions, cf., for example, FIG. 10 in DE- A-196 34 517) can be formed.
• the piston is labeled 2, the cylinder wall 3, the cylinder head 4 and the scooping chamber (compression chamber) 5.
• the outlet valve 7 is located in the region of the end face of the cylinder shown. It comprises the largest possible valve plate 8, which is attached to the cylinder head 4.
• the front edge of the cylinder wall 3 (or a section thereof) serves as the valve seat 9.
• the gas outlet chamber 11 to which a gas outlet (not shown) is connected.
• the gas inlet valve according to the invention is designated 12 in each case.
• the inlet valve 12 - like the outlet valve 7 - is in the region of the end face of the cylinder shown. linders arranged. In the cylinder head 4, in addition to the gas outlet chamber 11, there is a gas inlet chamber or line 14. The gas inlet valve 12 is located between the gas inlet chamber 14 and the scooping chamber 5. It is pressure-controlled and opens as soon as a sufficiently low pressure is created in the scooping chamber 5 during the suction stroke of the piston .
• inlet valve 12 and outlet valve 7 are arranged side by side.
• the valve plate 8 of the outlet valve 7 is fastened to the cylinder head 4 by means of the screw 15. It is actuated by the plunger 16 on the piston 2.
• the closure piece of the inlet valve 12 is a spring tongue 18, which is part of a valve plate 19 fastened between the cylinder and cylinder head 4. When the inlet valve 12 is closed, the spring tongue 18 of the mouth 20 of the inlet chamber or line 14 rests.
• FIGS. 2a to 2c show an inlet valve 12 fastened approximately centrally on the cylinder head 4, the closure piece 21 of which comprises a rotationally symmetrical valve tongue 22 which is connected to an edge 24 via annular spring sections 23 (FIG. 2b).
• the spring tongue 22 of the mouth 20 of the gas inlet chamber 14 lies in the scooping chamber 5.
• Either the sleeve 26 itself (eg from Viton) or an elastomer ring 29 form the valve seat.
• the edge 24 of the closure piece 21 is clamped between the fastening nut 27 and an elastomer ring 31.
• the fastening nut 27 has a hollow shaft which is equipped with cutouts 32 for the passage of the spring sections 23.
• the valve plate 8 of the gas outlet valve 7 surrounds the inlet valve 12 and can be pressure-controlled or - via the tappet 16 - piston-controlled.
• the closure piece 8 of the gas outlet valve 7 is fastened to the cylinder head 4 with the aid of an elastic bellows 35 (metal or elastomer material).
• the interior of the bellows 35 forms the gas inlet chamber 14.
• the gas enters the scoop chamber 5 via a bore 36 in the valve plate 8.
• the plate 8 of the gas outlet valve 7 is equipped or coated with an elastomer membrane 37.
• the membrane 37 is equipped with openings 39 which are arranged offset with respect to the bore 36 and which, with sufficient negative pressure in the scoop chamber 5, allow the gases to pass through (shown in FIG. 3, left half).
• a spring tongue 40 - similar to the solution according to Figure 1 - assigned, which is fastened to the valve plate 8 by means of the screw 41.
• FIG. 5 shows a valve seat 43 screwed tightly into a thread on the cylinder head 4 (elastomer ring 42) with passage bores 44.
• the passage bores 44 arranged on a circle are assigned an annular closure piece 45 which is under the action of a compression spring 46.
• the spring 46 is supported on a stroke limiter 47 and determines the pretension of the gas inlet valve 12.
• part of the cross-sectional area of the cylinder bore is used for the arrangement of the gas inlet 12; the majority, however, is available for the large-area gas outlet 7.
• the position of the gas inlet valve 12 is particularly advantageous since it can initiate its opening movement under pressure control immediately after the start of the suction stroke.
• the gas entry takes place via an opening 50 (bore or slot) opening laterally into the scooping chamber 5.
• the inlet valve 12 is located in a chamber 51 in the cylinder wall 3.
• the gas inlet line 14 opens into the chamber 51.
• the locking mechanisms of the solutions according to FIGS. 6 to 8 are similar to the locking mechanisms according to FIGS. 1, 2 and 5 (spring tongues 18, 21 or spring-loaded annular closure piece 45).
• a per se known non-return valve with a under the action of the compression spring 52 ⁇ stationary ball 53 as a closure piece, which is associated with a conically shaped seat 54.
• the bores 50 in the solutions according to FIGS. 6 to 9 are each located in the immediate vicinity of the end face of the cylinder wall 3 facing the outlet valve 7, so that the valves 12 open under pressure control as early as possible when the suction stroke begins.
• a further gas inlet 55 controlled by the piston 2 (FIG. 8) which is designed as a circumferential groove 56 in the cylinder wall 3.
• the gas inlet line 14 also opens into this groove 56.
• the solutions according to FIGS. 6 to 9 have the advantage that the cross section of the outlet valve 7 is not impaired by the arrangement of a gas inlet valve 12 and that there is sufficient space on the side next to the cylinder for accommodating the gas inlet valve 12.
• an exhaust valve that is free of damage is easy to implement. It is essential in these solutions that the gas inlet 50 is located in the immediate vicinity of the end face of the cylinder bore, so that the gas inlet valve 12 is able to open under pressure control when the suction stroke begins.
• the piston 2 is equipped on the end face with a sleeve 61 with an outer lip 62. Furthermore, the piston 2 with one axially extending groove 63, which - when the piston 2 is at its top dead center - extends from the piston end to the gas inlet 55 (ring ⁇ groove 56 in the cylinder wall 3).
• the lip 62 which forms the gas inlet valve 12 together with the cylinder wall, lifts off the cylinder wall, so that the connection between the gas inlet 55 and the scoop chamber 5 is established via the groove 63.
• the function of the groove 63 can also fulfill an annular gap between the piston skirt and the cylinder wall.
• the inlet 55 expediently has the form of a circle of holes so that the sleeve can be moved to the bottom dead center via the inlet.
• the gas inlet can be located in the end face 66 of the piston 2.
• the gas inlet valve 12 is designed as a tongue valve ( Figures 1 and 6).
• the spring tongue 18 is fastened to the piston 2 by means of the screw 65 and lies in the closed state of the mouth 20 of the gas inlet channel 14.
• Other valve shapes are also possible (e.g. ball valve).
• NEN valve plate 8 in Figure 3, piston face in Figures 4 and 10, piston shirt in Figure 5, cylinder wall in Figure 6
• the closure elements and / or seats of the inlet valves 12 can also be equipped with a layer.
• the materials are selected (e.g. elastomer or polytetrafluoroethylene).
• the actuation of the outlet valve 7 can be pressure- or piston-controlled.
• Valves made of spring steel sheet, which combine the valve plate and spring tongues in one piece.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Compressor (AREA)
• Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
• Reciprocating Pumps (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7904655

Family Applications (1)

Country Status (5)

Cited By (3)

Families Citing this family (16)

Citations (11)

Family Cites Families (6)

• 1999
  • 1999-04-15 DE DE19917009A patent/DE19917009A1/de not_active Withdrawn
• 2000
  • 2000-03-03 WO PCT/EP2000/001845 patent/WO2000063557A1/de active IP Right Grant
  • 2000-03-03 DE DE50010975T patent/DE50010975D1/de not_active Expired - Lifetime
  • 2000-03-03 EP EP00909301A patent/EP1169572B1/de not_active Expired - Lifetime
  • 2000-03-03 AU AU31636/00A patent/AU3163600A/en not_active Abandoned
  • 2000-04-14 TW TW089106978A patent/TW571025B/zh active

Patent Citations (11)

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