Patent Description:
Patent Literature <NUM> describes an example of a breast pump that includes a main body, a diaphragm, and a handle. A hood and a bottle are attached to the main body. The hood is fitted to a breast, and the bottle collects milk. The diaphragm is arranged in an internal passage that connects the bottle and a milking port in the hood. The diaphragm causes the pressure of the internal passage to become negative. The handle is manually operated to move the diaphragm. When the diaphragm is lifted by operating the handle, the volume of the internal passage is increased so that the pressure of the internal passage becomes negative in the breast pump. The negative pressure collects the milk extracted from the nipple in a temporary reservoir that is part of the internal passage. When the internal passage returns from the negative pressure state to a normal pressure state, a valve of the temporary reservoir opens and the milk flows from the temporary reservoir into the bottle. Patent Literature <NUM> discloses a non-return valve.

It is important that hygiene be maintained in the internal passage through which the pumped milk flows, and the internal passage should be cleaned after use. For cleaning, parts such as the hood, bottle, and diaphragm are removed from the main body and cleaned with the hands or scrubbed with a brush.

In the breast pump, the handle is operated to deform the diaphragm and cause the pressure of the internal passage to be negative. The amount the diaphragm is displaced is in accordance with the amount the handle is manual operated. Thus, the displacement amount of the handle is not large. When the internal passage has a larger volume, the pressure changed by displacement of the diaphragm will be smaller. This will lower the milk-pumping efficiency. Accordingly, the internal passage is usually narrow and small in diameter and thus difficult to clean with fingers and the like.

An objective of the present disclosure is to provide a breast pump that allows the internal passage to be cleaned easily without lowering the milk-pumping efficiency. Solution to Problem.

Abreast pump that solves the above problem includes a main body, a diaphragm, a handle, a connecting portion, and a volume reduction portion. The main body includes a hood attaching portion, a bottle attaching portion, and an internal passage. A hood is attached to the hood attaching portion. The hood is fitted to a breast and includes a milking port. A bottle is attached to the bottle attaching portion and collects milk. The internal passage extends between the hood attaching portion and the bottle attaching portion. The diaphragm is attached to the internal passage and is configured to generate negative pressure in the internal passage. The handle is manually operated. The connecting portion connects the diaphragm and the handle and is configured to displace the diaphragm in a lifting direction in accordance with movement of the handle. The volume reduction portion is inserted into the internal passage and is configured to reduce a volume of the internal passage.

With the above structure, even though the internal passage is increased in diameter to be cleaned easily, the volume reduction portion is inserted into the portion where the diameter is increased. Thus, the volume of the internal passage is not increased, and decreases in the milk-pumping efficiency are minimized.

In the breast pump, the connecting portion is a lift plate that includes a plate portion and a connection projection. The plate portion is arranged on an inner surface of the diaphragm. The connection projection extends from the plate portion through the diaphragm, projects out of an outer surface of the diaphragm located at a side opposite to the inner surface, and is connected with the handle. The volume reduction portion is arranged on the plate portion.

With this structure, the volume reduction portion is arranged on the lift plate. This facilitates processes like cleaning and assembling/disassembling. The volume reduction portion is moved in cooperation with the movement of the handle.

In the above breast pump, the handle may be pivotally attached to the main body and configured to lift the diaphragm using the connecting portion in a direction intersecting a bottle axis that extends in a height direction of the bottle. With this structure, the volume reduction portion is moved in the internal passage in accordance with the pivoting operation of the handle.

In the above breast pump, the internal passage may include a negative pressure passage closed by the diaphragm, and the volume reduction portion may be inserted in the negative pressure passage. With this structure, the volume reduction portion reduces the volume of the negative pressure generation passage.

In the above breast pump, the breast pump may include a gap formed between an inner circumferential surface of the negative pressure generation passage and an outer circumferential surface of the volume reduction portion. With this structure, the gap allows the volume reduction portion to be smoothly reciprocated in the negative pressure generation passage.

The present invention allows the internal passage to be cleaned easily while minimizing decreases in the milk-pumping efficiency.

A breast pump will now be described with reference to <FIG>.

As shown in <FIG>, a breast pump <NUM> is a manual breast pump that is sized so that a user can operate it with one hand. The breast pump <NUM> includes a main body <NUM>, a bottle <NUM>, a hood <NUM>, a diaphragm <NUM> (refer to <FIG>), a handle <NUM>, a handle base <NUM>, and a lift plate <NUM>.

The main body <NUM> is a member to which the bottle <NUM> is connected and the hood <NUM> is attached. The bottle <NUM> collects milk. The hood <NUM> is fitted to a breast. The main body <NUM> is a molded product of a synthetic resin material that is hard and light in weight. Specifically, the main body <NUM> is formed from a synthetic resin material such as polypropylene, polycarbonate, polycycloolefin, polyethersulfone, and/or polyphenylsulfone.

As shown in <FIG>, the main body <NUM> includes a bottle attaching portion <NUM>, a hood attaching portion <NUM>, and an internal passage <NUM>. The bottle attaching portion <NUM> is located toward a lower side of the main body <NUM> than the hood attaching portion <NUM>. The bottle <NUM> is a container that collects milk and includes an open bottle portion 12a connected to the bottle attaching portion <NUM>. An external thread 12b is formed in the outer circumferential surface of the circumferential wall of the open bottle portion 12a. When an artificial nipple is attached to the open bottle portion 12a instead of the main body <NUM>, the bottle <NUM> can be used as a feeding bottle. The bottle attaching portion <NUM> includes a recess allowing the open bottle portion 12a to be fastened therein. The inner circumferential surface of the bottle attaching portion <NUM> defining the recess includes an internal thread 21a that can be mated with the external thread 12b.

The hood attaching portion <NUM> is cylindrical. The hood <NUM> is dome-shaped or horn-shaped in correspondence with the shape of a breast. The hood <NUM> includes a large-diameter portion 13a and a cylindrical portion 13b. The large-diameter portion 13a is fitted to a breast. The cylindrical portion 13b is arranged at the peak of the large-diameter portion 13a. The large-diameter portion 13a includes a milking port 13c. In the large-diameter portion 13a, an elastic pad or the like is attached to the edge of the open end so that the large-diameter portion 13a can be tightly fitted to the breast. The cylindrical portion 13b is inserted into and fitted in the hood attaching portion <NUM>.

As shown in <FIG>, the internal passage <NUM> is arranged inside the main body <NUM>. The internal passage <NUM> extends between and connects the bottle attaching portion <NUM> to the hood attaching portion <NUM>. Also, the internal passage <NUM> extends between and connects the bottle attaching portion <NUM> and the hood attaching portion <NUM> to an attachment end <NUM> where and the diaphragm <NUM> is attached. The internal passage <NUM> includes an inflow passage <NUM>, a temporary reservoir <NUM>, and a negative pressure generation passage <NUM>.

The inflow passage <NUM> connects the hood attaching portion <NUM> and the temporary reservoir <NUM>. The inflow passage <NUM> is located at the inner side of the hood attaching portion <NUM> and extends downward to the temporary reservoir <NUM>. The temporary reservoir <NUM> is located at the inner side of the bottle attaching portion <NUM> and extends downward. The temporary reservoir <NUM> is an open area for temporarily collecting the milk flowing from the inflow passage <NUM> when negative pressure is generated. For example, the temporary reservoir <NUM> is lies along a bottle axis 12x. The bottle axis 12x is parallel to the center axis of the bottle <NUM> that extends in a height direction (up-down direction) of the bottle <NUM> when attached to the bottle attaching portion <NUM>. In an example, the centerline of the temporary reservoir <NUM> coincides with the bottle axis 12x. The lower end of the temporary reservoir <NUM> faces the open bottle portion 12a in a state in which the bottle <NUM> is attached to the bottle attaching portion <NUM>. The angle of the inflow passage <NUM> with respect to the temporary reservoir <NUM>, that is, the angle θ1 of the center line 25x of the inflow passage <NUM> with respect to the bottle axis 12x of the temporary reservoir <NUM>, is the angle at which milk flows from the inflow passage <NUM> into the temporary reservoir <NUM>.

A valve member <NUM> is attached to the lower end of the temporary reservoir <NUM> inside the open bottle portion 12a. The valve member <NUM> is a check valve, for example, a duckbill valve. The valve member <NUM> checks backflow of milk and air from the bottle <NUM> to the main body <NUM>. Also, the valve member <NUM> partitions the internal passage <NUM> and the interior space of the bottle <NUM> to form a negative pressure state in the internal passage <NUM>. The valve member <NUM> is formed from a synthetic resin material that is flexible and elastic, such as silicone rubber and/or elastomer, or natural rubber.

The valve member <NUM> includes a pair of flexible flaps, and a slit is formed between the flaps. When the internal passage <NUM> is in a negative pressure state, the flaps of the valve member <NUM> abut each other and close the slit. This closes the lower end of the temporary reservoir <NUM> to temporarily collect the milk flowing from the inflow passage <NUM>. When the pressure of the internal passage <NUM> becomes normal, the flaps separate from each other and open the slit. This connects the temporary reservoir <NUM> and the inside of the bottle <NUM> so that the milk collected in the temporary reservoir <NUM> flows into the bottle <NUM>.

The negative pressure generation passage <NUM> is separate from the inflow passage <NUM> and branched off from the temporary reservoir <NUM>. Specifically, the negative pressure generation passage <NUM> extends upward from the upper end of the temporary reservoir <NUM> or the outlet of the inflow passage <NUM> leading to the temporary reservoir <NUM>. In an example, the negative pressure generation passage <NUM> is larger than the inflow passage <NUM> in diameter. Further, in an example, the negative pressure generation passage <NUM> is larger than the temporary reservoir <NUM> in diameter. The negative pressure generation passage <NUM> has a diameter allowing a user to insert, for example, a finger. The angle of the negative pressure generation passage <NUM> with respect to the temporary reservoir <NUM>, that is, the angle θ2 of the center axis 27x of the negative pressure generation passage <NUM> with respect to the bottle axis 12x of the temporary reservoir <NUM> is set so that milk does not flow backward toward the diaphragm <NUM>. The negative pressure generation passage <NUM> is tilted at the side of the temporary reservoir <NUM> opposite the inflow passage <NUM>. The upper end of the negative pressure generation passage <NUM> corresponds to the attachment end <NUM> where the diaphragm <NUM> is attached. The attachment end <NUM> is flanged and extends outward to increase the area of the opening. Further, the outer circumferential surface of the attachment end <NUM> includes an attachment groove 24a for attachment of the diaphragm <NUM>.

The diaphragm <NUM> is a negative pressure generation member that causes the pressure of the internal passage <NUM> to become negative. The diaphragm <NUM> is formed from a synthetic resin material that is flexible and elastic such as silicone rubber and/or elastomer, or natural rubber. The diaphragm <NUM> is engaged with the attachment groove 24a to close the attachment end <NUM>. The internal passage <NUM> includes three ends, namely, the end of the inflow passage <NUM> where the hood <NUM> is attached, the lower end of the temporary reservoir <NUM> where the valve member <NUM> is attached, and the attachment end <NUM>. When the hood <NUM> is fitted to a breast and the milking port 13c is closed, that is, the end of the inflow passage <NUM> is closed, the other ends, which are the lower end of the temporary reservoir <NUM> and the attachment end <NUM>, are respectively closed by the valve member <NUM> and the diaphragm <NUM>. Thus, the internal passage <NUM> becomes a substantially sealed space. The lift plate <NUM> is arranged at the inner side of the diaphragm <NUM> and serves as a connecting portion that connects to the handle <NUM>.

The lift plate <NUM> is a molded body of a synthetic resin material that is harder than the diaphragm <NUM>. The lift plate <NUM> is formed from a synthetic resin material such as polycarbonate, polycycloolefin, polyethersulfone, and/or polyphenylsulfone. The lift plate <NUM> is a portion connecting the handle <NUM> and includes a plate portion <NUM> and a connection projection <NUM>. The plate portion <NUM> is arranged on the inner surface of the diaphragm <NUM>. The connection projection <NUM> projects from a central part of the surface of the plate portion <NUM> that faces the diaphragm <NUM>. The central part of the diaphragm <NUM> includes a through hole 14a through which the connection projection <NUM> projects outward from the diaphragm <NUM>. The connection projection <NUM> has a spherical tip and an engagement groove 32a that is formed in the lower end of the sphere.

An insertion member <NUM> is attached to the plate portion <NUM>. The insertion member <NUM> includes a volume reduction portion 30a and an attachment flange 30b. The attachment flange 30b is attached to and overlapped with the plate portion <NUM>. In an example, the attachment flange 30b may be fixed to the plate portion <NUM> with an adhesive or the like. Alternatively, the outer circumferential portion of the attachment flange 30b may be engaged with an engagement piece arranged on the plate portion <NUM>. Furthermore, the attachment flange 30b may be integrated with the plate portion <NUM> by a welding process such as ultrasonic welding or heat-welding. The volume reduction portion 30a is a cylindrical portion projecting from the attachment flange 30b.

The volume reduction portion 30a is inserted into the negative pressure generation passage <NUM> to reduce the volume of the negative pressure generation passage <NUM>. The volume reduction portion 30a has a diameter such that a gap 30c is formed between the outer circumferential surface of the volume reduction portion 30a and the inner circumferential surface of the negative pressure generation passage <NUM>. The volume reduction portion 30a projects from the attachment flange 30b and is inserted into the interior space of the negative pressure generation passage <NUM>. The projecting shape of the volume reduction portion 30a corresponds to the internal shape of the negative pressure generation passage <NUM>, into which the volume reduction portion 30a is inserted. In an example, the volume reduction portion 30a is a projection portion that has the form of a column or a cylinder with a closed end. In an example, the negative pressure generation passage <NUM> has the form of a hollow cylinder and includes an interior space. The volume reduction portion 30a is set to have an outer diameter that is smaller than the inner diameter of the negative pressure generation passage <NUM>.

When the negative pressure generation passage <NUM> is inserted, the gap 30c allows the volume reduction portion 30a to smoothly move upward and downward even if the volume reduction portion 30a is slightly tilted with respect to the negative pressure generation passage <NUM>. Further, the volume reduction portion 30a has a length set such that the volume reduction portion 30a will not close the outlet of the inflow passage <NUM> leading to the temporary reservoir <NUM> when the diaphragm <NUM> is lifted. Thus, when negative pressure is generated, milk flows from the inflow passage <NUM> into the temporary reservoir <NUM>. The volume reduction portion 30a has a length set such that the volume reduction portion 30a will be located at the outlet of the inflow passage <NUM> or the upper end of the temporary reservoir <NUM> when the diaphragm <NUM> is not deformed.

The handle <NUM> is supported by the handle base <NUM> and pivots relative to the main body <NUM>. The handle base <NUM> is attached in a rotatable manner to a cylindrical bottom part of the attachment end <NUM>. The handle base <NUM> is rotatable about the base part of the attachment end <NUM> in a circumferential direction within a range excluding the hood attaching portion <NUM>, which is for attachment of the hood <NUM>.

The handle base <NUM> includes an attachment portion <NUM> and a pivot support piece <NUM>. The attachment portion <NUM> is C-shaped. The bottom part of the attachment end <NUM> is cylindrical and includes a groove-like guide portion <NUM> extending in the circumferential direction. The attachment portion <NUM> is fitted to the guide portion <NUM> in a manner rotatable in the circumferential direction. The rotation range of the handle base <NUM> is limited to the range described above by having the ends of the C-shaped attachment portion <NUM> come into contact with the ends of the guide portion <NUM>. The pivot support piece <NUM> is a curved elongated piece extending upward from the attachment portion <NUM> such that the distal end of the pivot support piece <NUM> is located upward of the diaphragm <NUM>. The distal end of the pivot support piece <NUM> includes a pivot shaft <NUM> that pivotally supports the handle <NUM>.

The handle <NUM> is formed from a synthetic resin material such as polycarbonate, polycycloolefin, polyethersulfone, and/or polyphenylsulfone. The handle <NUM> includes a lifter <NUM> and a lever <NUM>. The lifter <NUM> pulls the diaphragm <NUM> using the lift plate <NUM> and includes a pit 37a. The bottom surface of the pit 37a includes an engagement hole 37b. The connection projection <NUM> of the lift plate <NUM> is inserted through the engagement hole 37b so that the edge of the engagement hole 37b engages the engagement groove 32a. In this manner, the handle <NUM> is connected to the diaphragm <NUM> by the lift plate <NUM> so that the diaphragm <NUM> can be lifted. Further, the handle <NUM> is rotatable relative to the connection projection <NUM>.

The lever <NUM> extends downward and toward the bottle <NUM> and is used as a grip. The handle <NUM> has a curved outer surface to allow for easy handling and is held by the user with fingers other than the thumb. The lever <NUM> is gradually curved outward. A shaft support <NUM> is arranged at the inner side of the handle <NUM> near the boundary between the lever <NUM> and the lifter <NUM> and engaged with the pivot shaft <NUM>. When the pivot shaft <NUM> is pivotally engaged with the shaft support <NUM>, the handle <NUM> is supported and pivots relative to the main body <NUM>. This portion serves as a fulcrum where the handle <NUM> is moved back and forth. The handle <NUM> is manually pivoted in arrowed direction D1 that is a pivot operation direction, and the handle <NUM> is pivoted by the resiliency of the diaphragm <NUM> in arrowed direction D2 that is a recovery direction.

The main body <NUM> includes a recess <NUM> below the hood attaching portion <NUM> opposing the handle <NUM>. The recess <NUM> engages the base of the thumb of the user. Specifically, in the breast pump <NUM>, the user places fingers other than the thumb on the lever <NUM> with the base of the thumb engaged with the recess <NUM> to squeeze the handle <NUM> and pivot the handle <NUM> about the pivot shaft <NUM>.

The direction in which the handle <NUM> lifts the diaphragm <NUM> using the lift plate <NUM> is perpendicular to the main surface of the diaphragm <NUM>. That is, the handle <NUM> lifts the diaphragm <NUM> using the lift plate <NUM> in arrowed direction D1 intersecting the bottle axis 12x rather than the direction in which the bottle axis 12x extends. This allows the gap 30c to be reduced and the volume of the internal passage <NUM> to be decreased.

The operation of the breast pump <NUM> will now be described.

The breast pump <NUM> is assembled as described below. The valve member <NUM> is attached to the temporary reservoir <NUM> of the main body <NUM>. The lift plate <NUM> is integrated with the insertion member <NUM>, and the volume reduction portion 30a is inserted into the negative pressure generation passage <NUM>. The connection projection <NUM> is inserted through the through hole 14a, and the diaphragm <NUM> is attached to the attachment end <NUM>. The handle base <NUM> is attached to the guide portion <NUM> of the main body <NUM>. The connection projection <NUM> is inserted through the engagement hole 37b of the handle <NUM>, and the edge of the engagement hole 37b is engaged with the engagement groove 32a. Further, the pivot shaft <NUM> of the handle base <NUM> is engaged with the shaft support <NUM> of the handle <NUM>. The bottle <NUM> is attached to the bottle attaching portion <NUM> of the main body <NUM>, and the hood <NUM> is attached to the hood attaching portion <NUM>.

As shown in <FIG> and <FIG>, when pumping milk, the user holds the breast pump <NUM> by placing fingers other than the thumb on the handle <NUM> with the base of the thumb engaged with the recess <NUM> of the main body <NUM>. Then, the hood <NUM> is fitted to the breast of the user so as to close the milking port 13c. As a result, the internal passage <NUM> becomes a substantially sealed space. In this case, the handle base <NUM> is guided by the guide portion <NUM> and the handle <NUM> is rotated about the connection projection <NUM> relative to the main body <NUM> in conformance with the body of the user or the like. This allows for easy handle operation by the user.

The handle <NUM> lifts the diaphragm <NUM> using the lift plate <NUM> when the handle <NUM> is manually pivoted in arrowed direction D1, in which the lever <NUM> approaches the side surface of the bottle <NUM>. In this case, the volume reduction portion 30a is also lifted inside the negative pressure generation passage <NUM>. This forms a negative pressure state in the internal passage <NUM>, and pumped milk flows from the inflow passage <NUM> into the temporary reservoir <NUM>. In a negative pressure state, the bottom of the temporary reservoir <NUM> is closed by the valve member <NUM>. Accordingly, the milk flowing from the inflow passage <NUM> collects in the temporary reservoir <NUM>.

When the user reduces the squeezing force, the resiliency of the diaphragm <NUM> pivots the handle <NUM> in arrowed direction D2 and returns the internal passage <NUM> to normal pressure. This opens the valve member <NUM> of the temporary reservoir <NUM>, and milk flows into the bottle <NUM>. The handle <NUM> is repetitively moved back and forth to pump milk. In this case, the volume reduction portion 30a is also reciprocated inside the negative pressure generation passage <NUM>.

Although the negative pressure generation passage <NUM> has a relatively large diameter and increases the volume of the internal passage <NUM>, insertion of the volume reduction portion 30a, which is integrated with the lift plate <NUM>, decreases the volume of the internal passage <NUM>. Thus, the pressure that changes when the diaphragm <NUM> is deformed is subtly affected.

After use, the breast pump <NUM> is disassembled as shown in <FIG> for cleaning. Specifically, the bottle <NUM>, the hood <NUM>, the handle <NUM>, the handle base <NUM>, the diaphragm <NUM>, and the lift plate <NUM>, which is integrated with the volume reduction portion 30a, are removed from the main body <NUM>. Then, each part is cleaned with a hand or scrubbed with a brush. In particular, the negative pressure generation passage <NUM> of the internal passage <NUM> in the main body <NUM> has a diameter allowing for insertion of a finger. Therefore, the negative pressure generation passage <NUM> can be thoroughly cleaned with a finger or a brush. After cleaning, the breast pump <NUM> is assembled as described above.

The breast pump <NUM> has the advantages described as below.

The above-described embodiment may be modified as follows.

As shown in <FIG>, the negative pressure generation passage <NUM> may be arranged so that the center axis 27x coincides with the bottle axis 12x. In this case, the direction in which the volume reduction portion 30a is moved corresponds to arrowed direction D1 that intersects the bottle axis 12x. Thus, the volume reduction portion 30a will be tilted inside the negative pressure generation passage <NUM>. Accordingly, the gap 30c between the outer circumferential surface of the volume reduction portion 30a and the inner circumferential surface of the negative pressure generation passage <NUM> is set to be greater than that of the above embodiment. This allows the volume reduction portion 30a to be smoothly moved in the negative pressure generation passage <NUM> even when tilted and reciprocated.

As shown in <FIG>, the volume reduction portion 30a is moved in arrowed direction D1 that intersects the bottle axis 12x. The volume reduction portion 30a may be curved along arrowed direction D1, and the negative pressure generation passage <NUM> may be curved along arrowed direction D1 in correspondence with the shape of the volume reduction portion 30a. This reduces the gap 30c between the outer circumferential surface of the volume reduction portion 30a and the inner circumferential surface of the negative pressure generation passage <NUM> from that shown in <FIG>. When the gap 30c is reduced, the volume reduction portion 30a further effectively reduces the volume of the internal passage <NUM>.

The lift plate <NUM> may be formed integrally with the insertion member <NUM> as a single component. This decreases the number of parts.

The lift plate <NUM> may be adhered and fixed to the outer surface of the diaphragm <NUM>. In this case, the volume reduction portion 30a is integrally arranged on the inner surface of the diaphragm <NUM>.

The lift plate <NUM> may be omitted, and the connection projection <NUM> may be arranged on the outer surface of the diaphragm <NUM> as a connecting portion connected to the engagement hole 37b of the handle <NUM>.

The volume reduction portion 30a may be separated from the diaphragm <NUM>. In this case, in an example, the volume reduction portion 30a is connected to the attachment flange 30b by a spacer that maintains a constant distance between the volume reduction portion 30a and the attachment flange 30b. Alternatively, the volume reduction portion 30a is connected to the plate portion <NUM> of the lift plate <NUM> by a spacer. In an example, the spacer may be formed by one or more linear members or shafts that connect the volume reduction portion 30a and the attachment flange 30b or the plate portion <NUM>.

The insertion member <NUM> may be omitted, and the volume reduction portion 30a may be formed integrally with the diaphragm <NUM> as a single component. This structure also decreases the number of parts.

The distal end surface of the volume reduction portion 30a does not have to be flat and may be, for example, convex or concave.

The outer circumferential surface of the volume reduction portion 30a may have any outer form as long as the volume of the negative pressure generation passage <NUM> is reduced. For example, in side view, the circumferential surface of the volume reduction portion 30a may be corrugated, concave, or convex.

The projecting shape of the volume reduction portion 30a does not have to correspond to the internal shape of the negative pressure generation passage <NUM>, into which the volume reduction portion 30a is inserted. For example, the projecting shape (outer shape) of the volume reduction portion 30a may be a polygonal post such as a triangular post, a square post, and a hexagonal post, and the negative pressure generation passage <NUM> may have the form of a hollow cylinder. Alternatively, the projecting shape of the volume reduction portion 30a may be a column or a cylinder, and the internal shape of the negative pressure generation passage <NUM> may correspond to a polygonal post such as a triangular post, a square post, and a hexagonal post.

The structure of the internal passage <NUM> is not limited. For example, the temporary reservoir <NUM> may be omitted. In this case, the valve member <NUM> may be omitted.

The handle <NUM> may be directly supported by the main body <NUM> in a pivotal manner instead of being supported by the handle base <NUM>. In this case, the pivot support piece <NUM>, the pivot shaft <NUM>, and the like are integrated with the main body <NUM>.

The handle <NUM> may extend toward a user where the hood <NUM> is located instead of downward toward the bottle <NUM>. In this case, the user can pivot the handle <NUM> in a supination position with the palm facing upward.

The bottle <NUM> does not have to be attachable to and detachable from the bottle attaching portion <NUM> and may be formed integrally with the bottle attaching portion <NUM>. Further, the hood <NUM> does not have to be attachable to and detachable from the hood attaching portion <NUM> and may be formed integrally with the hood attaching portion <NUM>.

The inflow passage <NUM> and the temporary reservoir <NUM> may also have a diameter allowing a user to insert, for example a finger.

The negative pressure generation passage <NUM> does not have to be tilted with respect to the temporary reservoir <NUM>.

The lever <NUM> does not have to be gradually curved outward and may be linear. Alternatively, the lever <NUM> may have a distal end that is bent toward the main body <NUM>.

Claim 1:
A breast pump (<NUM>), comprising:
a main body (<NUM>) including
a hood attaching portion (<NUM>) to which a hood (<NUM>), fitted to a breast and including a milking port (13c), is attached,
a bottle attaching portion (<NUM>) to which a bottle (<NUM>) for collecting milk is attached, and
an internal passage (<NUM>) extending between the hood attaching portion (<NUM>) and the bottle attaching portion (<NUM>);
a diaphragm (<NUM>) attached to the internal passage (<NUM>) and configured to generate negative pressure in the internal passage (<NUM>);
a handle (<NUM>) that is manually operated;
a connecting portion (<NUM>) connecting the diaphragm (<NUM>) and the handle (<NUM>) and configured to displace the diaphragm (<NUM>) in a lifting direction in accordance with movement of the handle (<NUM>); and
a volume reduction portion (30a) inserted into the internal passage (<NUM>) and configured to reduce a volume of the internal passage (<NUM>),
characterized in that
the connecting portion (<NUM>) is a lift plate (<NUM>) that includes
a plate portion (<NUM>) arranged on an inner surface of the diaphragm (<NUM>), and
a connection projection (<NUM>) connected with the handle (<NUM>), the connection projection (<NUM>) extending from the plate portion (<NUM>) through the diaphragm (<NUM>) and projecting out of an outer surface of the diaphragm (<NUM>) located at a side opposite to the inner surface; and
the volume reduction portion (30a) is arranged on the plate portion (<NUM>).