U.S. patent application number 10/294920 was filed with the patent office on 2003-05-22 for oscillating restrictor.
This patent application is currently assigned to KNF Neuberger GmbH. Invention is credited to Hauser, Erwin.
Application Number | 20030095883 10/294920 |
Document ID | / |
Family ID | 7706528 |
Filed Date | 2003-05-22 |
United States Patent
Application |
20030095883 |
Kind Code |
A1 |
Hauser, Erwin |
May 22, 2003 |
Oscillating restrictor
Abstract
A reciprocating piston machine (1) with at least one inlet
and/or outlet valve that has a strip, tongue or lamella shaped
closing member (5). The opening movements (8) of the closing member
(5) are limited through a stroke restrictor (6) assigned to each
valve. The stroke restrictor (6) has or defines at least one
ventilation hole (8) inside the contact area of the closing member
(5). This ventilation hole (8) prevents the formation of air
cushions (7) between the closing member (5) and the corresponding
stroke restrictor (6) effectively. In the absence of the
ventilation hole (8), the air cushion (7) can limit the opening
movements of the closing member (5) prematurely, which in turn
could lead to the generation of additional noise.
Inventors: |
Hauser, Erwin; (Emmendingen,
DE) |
Correspondence
Address: |
VOLPE AND KOENIG, P.C.
SUITE 400, ONE PENN CENTER
1617 JOHN F. KENNEDY BOULEVARD
PHILADELPHIA
PA
19103
US
|
Assignee: |
KNF Neuberger GmbH
Freiburg
DE
|
Family ID: |
7706528 |
Appl. No.: |
10/294920 |
Filed: |
November 14, 2002 |
Current U.S.
Class: |
417/569 ;
137/855; 137/856 |
Current CPC
Class: |
Y10T 137/7891 20150401;
F04B 39/1073 20130101; Y10T 137/7892 20150401 |
Class at
Publication: |
417/569 ;
137/855; 137/856 |
International
Class: |
F04B 039/10 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 22, 2001 |
DE |
101 57 234.4 |
Claims
What is claimed is:
1. A reciprocating piston machine (1) with at least one inlet
and/or at least one outlet valve (3, 4) with a strip, tongue or
lamella shaped closing member (5), a stroke restrictor
corresponding to the valve (3, 4) to limit opening movements of the
closing member (5), wherein the stroke restrictor (6) includes or
defines at least one ventilation hole (8) in a contact region of
the closing member (5).
2. A reciprocating piston machine (1) according to claim 1, wherein
an external outline of the stroke restrictor (6) is complementing
to an external outline of the closing member (5).
3. A reciprocating piston machine (1) according to claim 1, wherein
the stroke restrictor (6) and the closing member (5) have strip or
tongue shape.
4. A reciprocating piston machine (1) according to claim 1, wherein
the stroke restrictor (6) has at least one ventilation hole (8),
with a point-shaped or circular cross section.
5. A reciprocating piston machine (1) according to claim 1, wherein
the stroke restrictor (6) has at least one ventilation hole (8)
with a longitudinally extended hole cross section aligned
lengthwise or crosswise to the stroke restrictor (6).
6. A reciprocating piston machine (1) according to claim 1, wherein
the stroke restrictor has a plurality of ventilation holes (8)
having axes which are parallel to one another, and the ventilation
holes (8) have a longitudinally extended opening cross 'section
that extends crosswise to the stroke restrictor (6).
7. A reciprocating piston machine (1) according to claim 1, wherein
the reciprocating piston machine (1) is a compressor.
8. A reciprocating piston machine (1) according to claim 1, wherein
the reciprocating piston machine (1) is a membrane pump.
Description
BACKGROUND
[0001] The invention relates to reciprocating piston machine with
at least one inlet and/or at least one outlet valve that has a
strip, tongue or lamella shaped closing member, the opening
movements of which are restricted by a stroke restrictor adjacent
to the valve.
[0002] Reciprocating piston machines are already known for use as
compressor pumps, the inlet and outlet valves of which have a
strip, tongue or lamella shaped closing member which perform the
task of opening and closing the inlet/outlet openings during the
pump cycle. To prevent the flexible closing member from expanding,
a stroke restrictor is provided for each closing member, which
limits the opening movement of the closing member. The outer
contours of these stroke restrictors are regularly adapted to the
outer contours of the closing members, and they are also in a
strip, tongue or lamella shape.
[0003] In case of fast pump cycles however, there is the danger
that an air cushion might be formed between the closing members and
the corresponding stroke restrictor, which may prematurely shut the
opening movement of the concerned closing member. The incomplete
opening movement can result in vibration of the closing members,
resulting in noise generation and an inadequate closing movement of
the valve, leading to degradation of the pump's performance.
SUMMARY
[0004] The object of the invention is therefore to develop a
reciprocating piston machine of the type mentioned at the above,
which is characterized by a constant performance level, and
especially by reduced noise generation.
[0005] The solution to this object according to the invention, in
the case of reciprocating piston machines of the types mentioned
earlier, is that the stroke restrictor should have at least one
ventilation hole inside the contact area of the closing member.
[0006] The stroke restrictors corresponding to the inlet and/or
outlet valves of the reciprocating piston machine in accordance
with the invention have at least one ventilation opening inside the
area of contact with the closing member. This ventilation opening
prevents the unwanted formation of air cushions between the closing
member and the stroke restrictors quite effectively. As the closing
member is not limited prematurely in its opening position by such
an air cushion, it can move back and forth between the valve seat
and the stroke restrictor even in fast pump cycles. As the closing
member is not exposed to natural oscillation, there is a reduction
in noise generation at a performance level that is constant.
[0007] To be able to support the closing member in its opening
position evenly, it is advantageous to adapt the external outline
of the stroke restrictor to the external outline of the closing
member. A preferred embodiment in accordance with the invention
ensures that the closing member and the stroke restrictors are
tongue or strip shaped.
[0008] The stroke restrictor can, for example, be made of a wire or
some other similar material frame adapted to the external contours
of the closing member, and it can limit the ventilation opening.
However, if the stroke restrictor is made of a strip or
tongue-shaped material, it can be advantageous if the stroke
restrictor has at least one ventilation hole, preferably several
ventilation holes with point or circle shaped hole cross
sections.
[0009] In another embodiment in accordance with the invention, it
is ensured that the stroke restrictor has at least one ventilation
hole with a hole cross section extended in a longitudinal or
crosswise direction of the stroke restrictor.
[0010] It can be advantageous if the stroke restrictor has several
ventilation holes, the axes of which are aligned parallel to one
another, so that they have a longitudinal hole cross section
extended crosswire to the direction of the stroke restrictor.
[0011] It is especially advantageous, if the reciprocating piston
machine in accordance with the invention is designed as a
compressor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Further characteristics of the invention are evident in the
following description of a preferred embodiment in accordance with
the invention, in connection with the claims as well as the
drawings.
[0013] The individual characteristics can be implemented singly or
together in an embodiment to the invention.
[0014] In the drawings:
[0015] FIG. 1 is a partial longitudinal section of a reciprocating
piston machine in the area of its inlet and outlet valves in which
one stroke restrictor is assigned to each of the closing members of
the valves.
[0016] FIG. 2 is a side view of the outlet valve of the
reciprocating piston machine according to FIG. 1, with the closing
member in the open position.
[0017] FIG. 3 is a top view of a stroke restrictor of the
reciprocating piston machine according to FIGS. 1 and 2, in which
the stroke restrictors in the contact area of the closing members
have several circle-shaped or point-shaped ventilation holes.
[0018] FIG. 4 is a top view of a stroke restrictor with a
ventilation hole that extends longitudinally along the stroke
restrictor's length.
[0019] FIG. 5 is a top view of a stroke restrictor with several
ventilation holes, the axes of which are aligned parallel to one
another, and that are longitudinally extended in a cross direction
to the length of the stroke restrictor.
[0020] FIG. 6 is a top view of a stroke restrictor without a
ventilation hole, and
[0021] FIG. 7 is a side view of the stroke restrictor of FIG. 6,
with the closing member in the open position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] A partial longitudinal section of a reciprocating piston
machine 1 is represented in FIG. 1 that serves as a pump and
especially as a compressor. The pump 1 includes a pump head 2
having an inlet valve 3 and an outlet valve 4 that alternately open
and close in a pump cycle. Each valve has a closing member 5 for
this purpose, which moves back and forth between an open and a
closed position.
[0023] A stroke restrictor 6 is provided for each valve to prevent
the closing member from expanding during the opening movements.
[0024] As is clear from FIGS. 3 to 6, the external outlines of the
stroke restrictors 6 are adapted to the external outlines of the
closing members 5 to which they are assigned. The stroke
restrictors are also designed as tongue-shaped units. The closing
member 5 and the stroke restrictor 6 assigned to it are aligned on
top of each other in such a way that in its open position, the
closing member 5 can lie uniformly against the stroke restrictor
6.
[0025] It can be recognized from FIG. 7 that especially in fast
pump cycles, an air cushion 7 may be formed between the closing
member 5 and the stroke restrictor 6, which limits the opening
movement of the closing member prematurely. The limited opening
movements can cause the closing member to oscillate. This kind of
oscillation is associated with the generation of additional noise,
which can lead to undesirable efficiency losses.
[0026] It can be recognized from FIGS. 1 to 5 that one stroke
restrictor is assigned to each of the valves 3, 4 of the pump. Each
stroke restrictor 6 has at least one ventilation hole 8 in the
contact area of the closing member 5.
[0027] This at least one ventilation hole 8 prevents the formation
of undesirable air cushions between the closing member 5 and the
assigned stroke restrictor 6 quite effectively. As the opening
movement of the closing member 5 is not restricted by such an air
cushion 7, it can move back and forth between the valve seat and
the stroke restrictor 6 even in fast pump cycles. As the closing
member 5 is not subjected to oscillation, generation of sound is
reduced under conditions of a constant performance level of the
pump.
[0028] It is recognizable in FIG. 3 that that the pump 1
illustrated in FIGS. 1 and 2 has a stroke restrictor 6 with several
ventilation holes 8 with point shaped or circle shaped cross
sections. These ventilation holes 8 are arranged here in two rows
aligned parallel to each other along the length of the stroke
restrictor.
[0029] As shown in FIG. 4 and FIG. 5, the stroke restrictor 6 can
also have at least one ventilation hole 8 with a longitudinally
extended hole cross section aligned lengthwise or in a cross
direction to the stroke restrictor 6.
[0030] While the stroke restrictor represented in FIG. 4 has a
ventilation hole 8 with a longitudinally extended hole cross
section aligned along the length of the stroke restrictor 6, the
stroke restrictor 6 represented in FIG. 5 has several ventilation
holes 8, the axes of which are aligned parallel to one another, and
that have longitudinally extended hole cross sections that are
arranged crosswise to the stroke restrictor 6.
* * * * *