Compact pump

A compact pump composed by combining a cylinder into which a diaphragm portion is to be inserted, a case which accommodates a driving portion for driving the diaphragm portion and a valve housing, and clamping and fixing a combination of the members with a spring.

BACKGROUND OF THE INVENTION
 a) Field of the Invention
 The present invention relates to a compact pump comprising a diaphragm
 portion composing a pump chamber and a valve body disposed in a valve
 chamber which are integrated with each other.
 b) Description of the Prior Art
 A conventional compact pump having a diaphragm which is, for example, of a
 type having three pump chambers has a configuration shown in FIGS. 1
 through 4.
 In FIG. 1, a reference numeral 1 represents a compact DC motor, a reference
 numeral 2 designates an output shaft of the motor 1, a reference numeral 3
 denotes a case which is formed in a cup shape having a bottom surface
 attached to a side surface of an output shaft of the motor 1 with screws
 4, a reference numeral 5 represents a collar fixed to the output shaft 2,
 a reference numeral 6 designates a driving shaft which is fixed to the
 collar 5 so that it is inclined at a predetermined angle relative to the
 output shaft 2 and its tip is located on a center axis of the output shaft
 2, a reference numeral 7 denotes a driving body having a hole 8, a
 reference numeral 9 represents a cylindrical support portion which is
 formed integrally with the driving body 7 so as to extend downward from
 its center, and a reference numeral 10 designates a steel ball which is
 used to reduce friction between the driving shaft 6 and the driving body
 7. The support portion 9 is loosely fitted over the driving shaft 6 and
 when the output shaft 2 rotates, the driving shaft 6 is rotated in an
 inclined condition, whereby a peripheral portion having the hole of the
 driving body 7 reciprocally moves up and down relative to the center of
 the driving body 7. A reference numeral 11 denotes a cylinder portion
 which is composed, for example, by forming three holes 12 in a plate like
 member as shown in FIG. 2, fixing three cylinders to these holes and
 forming three holes 13.
 A reference numeral 14 represents a diaphragm body made of a soft rubber, a
 reference numeral 15 designates three diaphragm portions having a form of
 hanging bells which are disposed at intervals of 120 degrees, integrated
 with one another and extended from the diaphragm body 14, a reference
 numeral 16 denotes a driving portion located at a center of the diaphragm
 portion, a reference numeral 17 represents a head portion which is formed
 at a tip of the driving portion 16 by way of a thin neck portion, and a
 reference numeral 18 designates a valve body portion which is formed
 integrally with the diaphragm body so as to extend upward from its center
 and has, for example, a cylindrical form. The head portion 17 runs through
 the hole 8 of the driving body 7 and extrudes from a bottom surface of the
 driving body 7, whereby the driving portion 16 is sustained by the driving
 body 7. At locations corresponding to the holes 13 in the cylinder portion
 11 (see FIG. 2), holes 19 are similarly formed in the diaphragm body 14
 (see FIG. 3).
 The diaphragm body 14 described above consists of the three diaphragm
 portions 15, the valve portion 18 and other portions which are integrated
 with one another and made of an elastic material such as rubber.
 A reference numeral 20 represents a lid body which serves also as a valve
 housing as shown in FIG. 4, a reference numeral 22 designates a hole which
 is formed to affix a valve, a reference numeral 23 denotes six air suction
 holes which are formed around the hole 22, a reference numeral 24
 represents a valve chamber portion which is formed upward over a center of
 the lid body 20 and a reference numeral 25 designates an exhaust hole
 which is formed in a thinned tip of the valve chamber portion 24.
 As shown in FIG. 1, the lid body 20 is combined with the cylinder portion
 11 with the diaphragm body 14 interposed, and fixed to the case 3 with
 screws 27 utilizing the holes 26 formed in the lid body 20, the holes 13
 formed in the cylinder portion 11 and the holes 19 formed in the diaphragm
 body 14 so that three pump chambers 28 are formed by the lid body 20 and
 the diaphragm portions 15.
 The lid body 20 has a common chamber 29 which is formed in the valve
 chamber portion 24 and notch-shaped grooves 30 which are formed inside
 (toward a center of the lid body) the circumferential portions of the air
 suction holes 23 (circumferences of portions at which the pump chambers 28
 are located) so as to communicate with the common chamber 29. Accordingly,
 the pump chambers 28 are communicated at centers thereof commonly to the
 common chamber 29. Furthermore, the valve body portion 18 is in contact
 with an inner circumferential surface of the valve chamber portion 24 so
 as to close communication paths.
 A reference numeral 31 represents a valve body which is made of a soft
 rubber and has a shape of an umbrella, a reference numeral 32 designates a
 pole brace which is formed integrally with the valve body 31 so as to
 extend upward from its center, a reference numeral 33 denotes a head which
 is formed on a tip of the pole brace 32 so as to have a diameter larger
 than that of the pole brace. The valve body 31 is formed so as to have a
 size large enough to cover the air suction holes 23 and the pole brace 32
 passes through the hole 22 so that the head 33 is located outside and will
 not come off the lid body 20.
 Now, description will be made of operations of the compact pump which is
 configured as described above. When the motor 1 is electrically energized
 and the output shaft 2 is rotated, the driving shaft 6 is also rotated,
 whereby points at ends of the outer circumferential surface of the driving
 body 7 sequentially move up and down to vibrate the driving portions 16 of
 the diaphragm portions 15 in a vertical direction with a phase difference
 of 120 degrees. That is, the diaphragm portions 15 make piston movements
 in the cylinder. The piston movements of the diaphragm portions
 periodically vary volumes of the pump chambers 28. When the driving
 portion 16 moves downward and the volume is increased, an internal
 pressure of the pump chamber 28 is lowered, whereby the valve body portion
 18 closes as it is brought into contact with the valve chamber portion 24,
 whereas the valve body 31 opens to introduce air through the air suction
 holes 23. When the driving portion 16 moves upward and the volume is
 reduced at the next stage, the internal pressure of the pump chamber 18 is
 enhanced, whereby the valve body 31 closes as it is brought into close
 contact with the lid body 20, whereas the valve body portion 18 which
 closes the groove 30 of the pump chamber is opened to exhaust air from the
 pump chamber through the groove 30, the common chamber 29 and the exhaust
 port 25, from the pump chamber 28 through the common chamber 29 and the
 exhaust port 25.
 This compact pump performs a pump function by operating the three diaphragm
 portions so as to repeat the movements described above with the definite
 phase difference, thereby suctioning air through the separate air suction
 holes 23 and exhausting the air through the common valve chamber 29 and
 the exhaust port 25.
 The diaphragm pump which has the configuration described above combines the
 case 3 accommodating the driving portion which consists of the collar 5
 attached to the output shaft 2 of the motor, the drive shaft 6, the
 driving body 7, etc. with the cylinder portion 11, the diaphragm body 14
 and the lid body (valve housing) 20, and fixes these members as a whole
 with the screws. Furthermore, the case 3, cylinder portion 11, lid body
 20, etc. are made of a synthetic resin material and these members which
 are made of the synthetic resin material are fixed with metallic screws.
 Accordingly, each of these members made of the synthetic resin material
 expands with a coefficient of expansion larger than that of the metallic
 screws and is deformed at portions fixed with the screws and surroundings
 thereof in particular when it is heated by operation of the pump and rise
 of ambient temperature. When temperature lowers after stopping operation
 of the pump or the expanded case and other members are cooled for a cause,
 in contrast, they are contracted and resume their initial conditions.
 When temperature is raised and lowered repeatedly as described above, the
 screws are loosened, thereby causing air leakage in some cases.
 FIG. 5 is schematic diagram showing locations, etc. of diaphragm portions
 15 arranged in a pump which has two diaphragm portions (pump chambers).
 Since tapped holes are formed at locations indicated by a reference
 numeral 37, the pump requires spaces for affixing it with screws utilizing
 the tapped holes, or such excessive spaces for affixing the pump with
 screws 27 as shown in FIG. 6. Similarly, FIG. 7 shows an outline of a pump
 which has a single diaphragm portion. This pump also requires spaces for
 fixing screws.
 Accordingly, pumps can be configured within certain limits and it is
 difficult to remarkably shorten external dimensions of pumps without
 reducing volumes (displacements) of pumps in particular.
 SUMMARY OF THE INVENTION
 A primary object of the present invention is to provide a compact pump
 which comprises a diaphragm body consisting of at least a diaphragm
 portion composing a pump chamber and a valve body portion formed at a
 location nearly in contact with the diaphragm portion which are integrated
 with each other, a cylinder portion into which the diaphragm portion is to
 be inserted, a case accommodating a driving portion which performs a pump
 function by driving the diaphragm portion, and a valve housing which has a
 suction valve at a location corresponding to each pump chamber, a valve
 chamber in which the valve body is to be inserted and an exhaust port
 communicating therewith, and is composed by sequentially overlapping and
 combining the case, the cylinder portion, the diaphragm body and the valve
 housing, and clamping and fixing these members as a whole with a spring.
 Another object of the present invention is to provide a compact pump which
 comprises a diaphragm body consisting of at least a diaphragm portion
 composing a pump chamber and a valve body portion formed at a location
 nearly in contact with the diaphragm portion which are formed integrally
 with each other, a cylinder portion into which the diaphragm portion is to
 be inserted, a case accommodating a driving portion which performs a pump
 function by driving the diaphragm portion, and a valve housing which has a
 suction valve at a location corresponding to each pump chamber, a valve
 chamber into which the valve body is to be inserted and an exhaust port
 communicating therewith, and is composed by interposing the diaphragm body
 between the cylinder portion and the valve housing, soldering the cylinder
 portion to the valve housing, further combining the case with the valve
 housing, the diaphragm portion and the cylinder portion which are soldered
 and integrally fixed, and clamping and fixing these members as a whole
 with a spring.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 FIG. 8 is a perspective view schematically showing an appearance of the
 compact pump preferred as a first embodiment of the present invention and
 FIG. 9 is a longitudinal sectional view of the first embodiment.
 In FIG. 9 showing the compact pump according to the present invention, a
 reference numeral 1 represents a motor, a reference numeral 2 designates a
 rotating shaft, a reference numeral 3 denotes a case for accommodating a
 driving portion, a reference numeral 5 represents a collar, a reference
 numeral 6 designates a driving shaft, a reference numeral 7 denotes a
 driving body, a reference numeral 11 represents a cylinder portion, a
 reference numeral 14 designates a diaphragm body, a reference numeral 15
 denotes a diaphragm portion, a reference numeral 18 represents a valve
 body portion, a reference numeral 20 designates a lid body (valve
 housing), a reference numeral 25 denotes a discharge port and a reference
 numeral 29 represents a common chamber: these members being substantially
 the same as those of the conventional pump shown in FIG. 1.
 As shown in these drawings, the compact pump according to the present
 invention is composed by combining the case 3, the cylinder portion 11,
 the diaphragm body 14 and the lid body 20, and clamping and fixing these
 members with a leaf spring 40 which is shown in the perspective view
 presented as FIG. 8. In addition, a reference numeral 20a represents a
 convexity which is formed on a circumference of an upper end surface of
 the lid body 20 to prevent a tip of the leaf spring 40 from coming off the
 lid body and it is desirable to shape a circumference of a lower end
 surface of the case 3 so as to have a similar form.
 The clamping with the leaf spring makes it extremely easy to fix the case,
 the cylinder portion and the diaphragm body. Moreover, the clamping with
 the leaf spring is capable, unlike screwing, of always maintaining the
 clamped and fixed conditions securely even when temperature is raised and
 lowered due to operation and stop of the pump (even in an environment
 where temperature is raised and lowered repeatedly).
 A plan view of the diaphragm body 14 is shown in FIG. 10, wherein a
 reference numeral 15 represents the diaphragm portion and a reference
 numeral 43 designates a convexity formed around the diaphragm portion 15.
 The first embodiment of the present invention is configured to be composed
 by combining the case 3, the cylinder portion 11 and the lid body (valve
 housing) 20 as shown in FIG. 8, and then clamping and fixing these members
 with the leaf spring 40, and can be assembled extremely easily.
 Furthermore, when the convexities 43 are formed around the diaphragm
 portions 15 of the diaphragm body 14 as shown in FIG. 10 and the pump is
 clamped and fixed with the leaf spring 40 as shown in FIG. 8, the
 convexities 43 are compressed and function to seal pump chambers
 completely. Moreover, the leaf spring which is adopted in place of
 clamping screws makes the pump free from a problem of rattling since a
 clamping force of the leaf spring is not weakened even when a volume (an
 outside diameter) of the pump is varied by expansion due to temperature
 rise caused by operating the pump (in a high temperature environment) and
 contraction due to temperature drop after stopping the pump. Accordingly,
 the convexities formed around the diaphragm portions provide sealing which
 is always secure and highly airtight for a long term, thereby making is
 possible to obtain a pump which has extremely high performance.
 FIG. 11 shows a modification of the first embodiment of the present
 invention, wherein similar convexities 44 are formed, in place of the
 convexities on the diaphragm body, so as to surround air suction holes 23
 on a bottom surface of a lid body (valve housing) 20. When a case 3, a
 cylinder portion 11, a diaphragm body 14 and the lid body 20 are clamped
 and fixed with a leaf springs 40 after these members are assembled, the
 convexities 44 formed on the lid body 20 are pressed to the diaphragm body
 14 and eat into the diaphragm body 14 while deforming it, whereby pump
 chambers are sealed completely. Furthermore, the clamping with the leaf
 spring is capable of always maintaining airtightness regardless of
 temperature variations such as those described above.
 FIG. 12 is a perspective view showing an appearance of a pump according to
 the present invention which has, like a conventional example shown in FIG.
 6, two pump chambers 15 arranged as shown in FIG. 13.
 The pump according to the present invention shown in FIG. 12 has the same
 configuration comprising a case 3, a cylinder portion 11, a diaphragm body
 14 and a lid body 20, except for cylinders and diaphragm portions which
 are used in pairs respectively.
 This embodiment also permits easily clamping and affixing the case 3, the
 cylinder portion 11, the diaphragm body 14 and the lid body 20 with a leaf
 spring 40 after these members are combined with one another.
 Since this embodiment uses no screw for affixing, it makes it unnecessary
 to reserve the spaces for screwing which are required for the conventional
 example, thereby making it possible to configure a pump extremely compact.
 When convexities are formed around diaphragm portions on a diaphragm body
 as in the pump preferred as the first embodiment, the pump shown in FIG.
 12 always assures complete sealing with the convexities which are clamped
 by the leaf spring.
 The concept of the present invention is applicable also to a pump which has
 a pump chamber like a conventional example shown in FIG. 7. That is, a
 pump chamber is disposed as shown in FIG. 14 in this case.
 FIG. 15A shows a second embodiment of the compact pump according to the
 present invention. This embodiment uses rod springs (linear springs) which
 are shaped as shown in FIG. 15B, in place of a leaf spring, to clamp and
 fix a combination of a case, a cylinder portion, a diaphragm body and a
 lid body.
 A diameter of a driving motor used in a compact pump may be smaller than a
 diameter of its pump portion. In such a case, a compact pump is assembled
 by forming grooves 41 outside a motor 1 in a pump portion consisting of a
 combination of a case 3, a cylinder portion 11, a diaphragm body 14 and a
 lid body 20 as shown in FIG. 15A, and clamping and fixing the case 3, the
 cylinder portion 11, the diaphragm body 14 and the lid body 20 by engaging
 the rod spring 42 shown in FIG. 15B along the grooves 41 as shown in FIG.
 15A.
 FIG. 16A shows an example wherein a compact pump which has three pump
 chambers, for example, is clamped with a rod spring shown in FIG. 16B.
 In this example, a cylindrical groove 41 is formed in a bottom surface of a
 case 3 (on a side to clamp a motor 1), a portion 42a of a rod spring 42 is
 bent into an arc shape as shown in FIG. 16B, and a pump is clamped and
 fixed with this spring as shown in FIG. 16A.
 It may be feared that the rod springs get off the compact pump preferred as
 the second embodiment shown in FIG. 15A or FIG. 16A after it is clamped
 and fixed with the rod springs. Therefore, the grooves are formed in the
 case 3 and so on to prevent the rod springs from deviating. When grooves
 are to be formed on a side of the case 3 which is to be in brought into
 contact with the motor, the motor 1 can be brought into close contact with
 the case 3 on the surface by forming grooves in the surface to be brought
 into contact with the motor 1 so as to have a depth larger than a diameter
 of rod springs and disposing the rod springs in the grooves. Even when the
 motor has a diameter which is not smaller than that of the case 3 (a
 diameter of the pump portion), it is therefore possible to obtain the
 compact pump preferred as the second embodiment of the present invention,
 or a compact pump fixed with rod springs.
 In case of a pump which is composed by combining and integrating a valve
 housing, a cylinder portion and a case like the compact pump according to
 the present invention, the valve housing and other members are generally
 made of a synthetic resin material.
 Such a pump may generates heat during its operation and allow the case,
 etc. to be deformed. When the valve housing and a cylinder are deformed in
 particular, a gap is formed in a seam between these members. When these
 members are deformed remarkably, it is undesirably impossible to obtain
 sufficient airtightness even with the convexities formed on the diaphragm
 body 14 and the convexities formed on the valve housing 20.
 A third embodiment of the present invention is illustrated in FIG. 17,
 wherein a reference numeral 1 represents a motor, a reference numeral 2
 designates an output shaft of the motor 1, a reference numeral 3 denotes a
 case, a reference numeral 5 represents a collar, a reference numeral 6
 designates a driving shaft, a reference numeral 7 denotes a driving body,
 a reference numeral 11 represents a cylinder portion, a reference numeral
 14 designates a diaphragm body, a reference numeral 15 denotes a diaphragm
 portion, a reference numeral 18 represents a valve body portion, a
 reference numeral 20 designates a valve housing, a reference numeral 25
 denotes an exhaust port, a reference numeral 28 represents a pump chamber
 and a reference numeral 29 designates a common chamber. These members have
 structures which are the same as those of the compact pump shown in FIG.
 9.
 The pump preferred as the third embodiment has a structure wherein the
 cylinder portion 11 and the valve housing 20 are integrated with each
 other by ultrasonic soldering or the like at a circumferential portion of
 a boarder between those members with the diaphragm body 14 interposed
 between the cylinder portion 11 and the valve housing 20.
 The pump preferred as the third embodiment is composed by combining, an
 integrated assembly 50 with the case 3, and clamping and fixing these
 members with leaf springs or the like, or has a structure which is the
 same as that of the pump shown in FIG. 8, except for the cylinder portion
 and the valve housing which are integrated with each other.
 Now, a method to solder the cylinder portion 11 to the valve housing 20
 will be described as an example below:
 An enlarged view of a portion 51 between the cylinder portion 11 and the
 valve housing 20 of the compact pump according to the present invention is
 shown in FIG. 18, wherein the members are shown in conditions before
 soldering to describe a soldering method. The cylinder portion 11 has a
 structure wherein a soldering convexity 52 is formed on a circumferential
 portion of the cylinder portion 11 and a concavity (step) lla having a
 depth corresponding to thickness of a diaphragm is formed inside the
 circumferential portion on which the convexity 52 is formed. After
 disposing the diaphragm body 14 on the convexity (step) 11a of the
 cylinder portion 11 so that the diaphragm portion 15 is inserted into a
 cylinder and overlaying the valve housing 20, ultrasonic soldering or the
 like is conducted utilizing the soldering convexity 52 to fuse the
 soldering convexity 52, thereby integrating a top surface of the
 circumferential portion of the cylinder portion 11 with a bottom surface
 of the valve housing 20 in a condition in contact with each other.
 Accordingly, the diaphragm body 14 is interposed between the cylinder
 portion 11 and the valve housing 20, and maintained in a sufficient
 airtight condition. Moreover, the cylinder portion 11 and the valve
 housing 20 which are integrated by the soldering cannot be deformed so
 remarkably as to lose the airtightness.
 FIGS. 19 and 20 are diagrams showing another example of soldering means for
 the cylinder portion and the valve housing. This means forms a plurality
 of soldering convexities 53 on the circumferential portion of the cylinder
 portion 11, bore holes 14b in the diaphragm body 14 at locations
 corresponding to the convexities 53 as shown in FIG. 20, disposes the
 soldering convexities 53 so that they are inserted into the holes 14b in
 the diaphragm body 14 at a stage to combine the diaphragm body 14 with the
 valve housing 20, and fixes and integrates the cylinder portion 11 to and
 with the valve housing by soldering utilizing the convexities 53.
 FIGS. 21 and 22 are diagrams showing another method to integrate the
 cylinder portion 11 with the valve housing 20 by soldering.
 Exemplified in FIGS. 21 and 22 is a compact pump which has two pump
 chambers and a rectangular parallelepiped appearance like that shown in
 FIG. 5 or FIG. 13.
 Soldering convexities 54 are formed on a surface of the cylinder portion 11
 which is located on a side of the valve housing as shown in FIG. 21 and
 notches 14c are formed in the diaphragm body 14 at locations corresponding
 to the convexities 54 as shown in FIG. 22. The diaphragm portion 14 is
 overlaid with the cylinder portion 11 shown in FIG. 21. At this stage, the
 members are disposed so that the convexities 54 on the cylinder portion 11
 are inserted into the notches 14c in the diaphragm portion 14.
 Furthermore, the valve housing (not shown) is overlaid and integrated by
 soldering utilizing the soldering convexities 54. Accordingly, the
 cylinder portion and the valve housing are integrated with each other and
 can maintain airtightness.
 FIG. 23A shows a fourth embodiment of the compact pump according to the
 present invention as another example of the pump according to the present
 invention which is similarly configured to prevent deformation in high
 temperature environments or due to temperature variations.
 The fourth embodiment is configured to overlay or dispose a metal sheet
 (reinforcement sheet) 55 on or with a valve housing 20, and then clamp and
 fix a pump with rod springs 42.
 Speaking concretely, the compact pump preferred as the fourth embodiment is
 similar to the compact pump shown in FIG. 15 which is clamped and fixed
 with the springs 42, but composed by combining a case 3, a cylinder
 portion 11 and a valve housing 20 with one another before clamping with
 springs 42, overlaying a reinforcement sheet 52 shown in FIG. 23A with the
 valve housing 20, and then clamping and fixing the members with the
 springs 42.
 Accordingly, the compact pump preferred as the fourth embodiment of the
 present invention is capable of preventing the valve housing 20, the
 cylinder portion 11 and other members from being deformed, and always
 maintaining airtightness even in environments which are kept at high
 temperatures or subjected to remarkable temperature variations.
 The compact pump preferred as the fourth embodiment suppresses deformation
 with the metal reinforcement sheet even when the valve housing and the
 cylinder portion which are made of a synthetic resin material are deformed
 in high temperature environments or due to heat generated by operating the
 pump, thereby being capable of maintaining an airtight condition with the
 metal reinforcement sheet and the clamping springs.
 The reinforcement sheet 55 to be used in the pump preferred as the fourth
 embodiment may be formed, for example, as shown in FIG. 23B, 23C or 23D.
 Out of reinforcement sheets shown in these drawings, the one shown in FIG.
 23B is a rectangular thin metal sheet which has a size nearly equal to an
 external size of the case 3, cylinder portion 11 or the valve housing 20
 and locates the exhaust port 25 of the pump outside the reinforcement
 sheet 55, a hole 56 having an optional shape and notches 57 corresponding
 to the grooves 41 in the pump shown in FIG. 15A.
 FIG. 23C shows a reinforcement sheet 55 having two sides which are
 partially bent to form reinforcing portions 58, whereas FIG. 23D shows a
 reinforcing portion 59 which is squeezed out in nearly a rhombus shape
 around the center hole 56 corresponding to the exhaust port.
 The reinforcement sheet requires definite strength for reinforcement and is
 desirably thin from a viewpoint of a weight of the pump as a whole.
 However, it is not preferable to configure the reinforcement sheet to be
 too thin so as to lack sufficient strength.
 The reinforcement sheets shown in FIG. 23C and FIG. 23D are examples which
 are made of thin sheets but have sufficient strength imparted by the
 reinforcement portions.
 Each of the reinforcement sheets shown in FIGS. 23B, 23C and 23D is assumed
 for application to a compact pump having the structure shown in FIG. 15A
 which has the rectangular outer circumferential shape (the shape of the
 convexity 20a), and is clamped and fixed with the rod springs 42. When the
 shape of the reinforcement sheet is modified, however, it is easily
 applicable to a compact pump which has the structure shown in FIG. 8, FIG.
 12 or FIG. 13.
 By using any one of the reinforcement sheets shown in FIGS. 23B, 23C and
 23D as in the fourth embodiment, it is possible to prevent a pump from
 being deformed due to heat generated by operating the pump, thereby
 allowing the pump to always maintain airtightness.
 The compact pump according to the present invention which uses the springs
 in place of fixing screws can be fixed in simple procedures and has
 external dimensions which are not changed by influences due to temperature
 rises and drops when in environments during the use are subjected to high
 temperature and remarkable temperature variations. Furthermore, the pump
 requires no spaces for screwing and can be configured more compact. When
 the pump has one or two pump chambers in particular, it can be configured
 remarkably more compact than a pump which requires screwing. Furthermore,
 integration of the cylinder portion with the valve housing by soldering or
 a use of the reinforcement sheet makes it possible to configure the pump
 so that it is almost free from deformation and maintains airtightness even
 when it is subjected to extremely high temperatures or kept in a high
 temperature condition for a long time.