Valve structure

摘要

To provide a valve structure in which a valve sheet is not fused to outer sheets when heat-sealing to a sealed bag. The left and right sides of three valve constituting sheets are side-sealed, and opposed valve constituting sheets are brought into close contact with each other to restrict a fluid from moving. The inside and outside of a bag body are partitioned by a partition seal, the valve is disposed across the inside and outside of the bag body, and welded to the bag body by the partition seal. One of the opposed surfaces of the valve constituting sheets is formed of a non-weldable film that is not welded by welding of the side seals and the partition seal. The side seals become non-welded portions and side-entering preventive sealed portions that block flows of the fluid into the movement channel are provided continuously to the partition seal.

主权项

1. A valve structure comprising:
a valve and a bag body made of sheets, the bag body comprising a partition seal partitioning the bag body into an inside portion and an outside portion, the valve comprising:
a plurality of valve constituting sheets disposed to layer each other;a fluid movement channel defined by a portion between opposed surfaces of at least two valve constituting sheets opposed to each other and layered together of the plurality of valve constituting sheets;side seals extending in an up-down direction defined by a movement direction from an upstream side to a downstream side of a fluid to be stored in the bag body, the side seals being provided on a left side and a right side of the fluid movement channel, respectively, and defining a width of the movement channel, the side seals being formed by welding the at least two valve constituting sheets, which define the fluid movement channel, to each other,wherein the fluid movement channel is configured to restrict the fluid to be received in the movement channel from moving when bringing the opposed valve constituting sheets into close contact with each other, the partition seal extends in a direction across the fluid movement channel, and the valve is disposed across the inside portion and the outside portion of the bag body, and welded to the bag body by the partition seal;a seal limiting sheet is provided on at least one of the opposed surfaces of the at least two valve constituting sheets which define the fluid movement channel, said seal limiting sheet including a non-weldable film on a whole surface thereof, said non-weldable film being positioned within the fluid movement channel and between the at least two valve constituting sheets which define the fluid movement channel, the non-weldable film extending to overlap with the side seals and not being welded to an opposed valve constituting sheet surface that faces the non-weldable film, such that the side seals include non-welded portions at a location where the side seals overlap with the non-weldable film, and such that the partition seal include non-welded portions at a location where the partition seal overlaps with the non-weldable film, wherein the non-weldable film maintains overlapping with the partition seal when the valve is in both an open state where the fluid is allowed to flow in the fluid movement channel, and a closed state where the fluid is restricted from flowing in the fluid movement channel; and side-entering preventive sealed portions provided on a more downstream side than the partition seal in a forward flow of the fluid, and on an outer sides in a left-right direction of the non-welded portions of the side seals, and provided continuously to the partition seal, said side-entering preventive sealed portions being configured to block flows of the fluid into the fluid movement channel from the non-welded portions of the side seals, wherein: the non-weldable film is not welded by welding of the side seals and the partition seal, a width of the seal limiting sheet in a direction vertical to the up-down direction is equal to a width of the plurality of valve constituting sheets in the direction vertical to the up-down direction, a width of the seal limiting sheet in the up-down direction is larger than a width of the partition seal in the up-down direction, an upper distal end of the seal limiting sheet is provided on a more upstream side than an upper distal end of the partition seal in the up-down direction, a lower distal end of the seal limiting sheet is provided on a more downstream side than a lower distal end of the partition seal in the up-down direction, and a lower distal end of each of the side-entering preventive sealed portions that is extended from the partition seal toward the more downstream side than the partition seal in the up-down direction is provided at the same position as, or on a more downstream side than, the lower distal end of the seal limiting sheet in the up-down direction.