JP2015039358A - Octagonal hollow tube for greenhouse - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hollow tube for a greenhouse which may be cheaply produced by utilizing a conventional hollow tube producing facility, have high fastening strength a variety of joints such as cross, and have easiness in machining to make curve.SOLUTION: A hollow tube for a greenhouse is consisting of a combination of: a hollow straight tube entirely having straight octagonal section in a longitudinal direction; and a hollow curve tube having straight octagonal section comprising a straight eave part at one end, an approximate straight roof part at the other end and a curve part curved in an arced-shape at middle section. The hollow curve tube comprises flat surfaces at a curve outer surface at the outermost position of the curve part and at a curve inner surface at the innermost position. In addition, at least parts of surfaces of the hollow curve tube and the hollow straight tube have increased friction coefficient by satin-finish processing for forming rough surfaces.

Description

  The present invention relates to a greenhouse hollow tube having a special cross-sectional shape.

Conventionally, a hollow tube having a circular cross section is often used as a pipe material for assembling into a greenhouse.
When this hollow tube having a circular cross section is joined in a vertical and horizontal cross shape using a conventionally known cross joint, the vertical hollow tube and the horizontal hollow tube are in direct contact with each other with their circular surfaces intersecting each other. It must be in a bonding form, and the contact area is a point contact with an extremely small contact area.
For this reason, when the steel material thickness of the cross joint is the same, the tightening strength depends on the frictional force of the point contact of the vertical and horizontal members, and there is a limit to improve the tightening strength of the joint.

Japanese Utility Model Laid-Open No. 06-067727

  An object of the present invention is to provide a greenhouse hollow tube that can be manufactured inexpensively and easily using conventional hollow tube manufacturing equipment and has high tightening strength of various joints such as a cross.

  In addition, greenhouse hollow tubes are usually the required number of arch members, which are two hollow tubes joined at the ridge, spaced apart in the ridge direction, and both lower ends thereof are inserted into the ground or used as a concrete foundation. The greenhouse is constructed by burying and then connecting a plurality of arch members with horizontal linear members by various joints.

By the way, this arch member is manufactured by connecting two hollow curved pipes obtained by bending a hollow straight pipe having a circular cross section at a central portion excluding both ends with a connecting pipe.
Therefore, the present invention also aims to provide a hollow tube for a greenhouse that is easy to bend and that is not damaged at a bending portion to be bent even if the cross-sectional shape of the hollow tube is polygonal. It is said.

In order to achieve the above-mentioned object, the invention according to claim 1 is a straight straight octagonal hollow straight tube over the entire length direction, a straight eave portion at one end and a substantially straight end at the other end. A hollow tube for a greenhouse composed of a combination of a hollow curved tube having an octagonal cross section that is a curved portion whose middle portion is curved in an arc shape at the roof portion, and the hollow curved tube is an outermost portion of the curved portion The curved outer surface located on the innermost side and the curved inner surface located on the innermost side are flat surfaces.
The invention according to claim 2 is characterized in that at least a part of the surface of the hollow curved tube and the hollow straight tube is roughened to increase the friction coefficient.

According to the first aspect of the present invention, the conventional hollow tube for a greenhouse that is a hollow tube having a circular cross section has a simple configuration having an octagonal cross section, and is inexpensive using a conventional hollow tube manufacturing facility. Therefore, it is possible to provide a hollow tube for a greenhouse that can be easily manufactured, has high tightening strength of various joints such as a cross, and is less damaged in a bent portion subjected to bending.
According to the invention of claim 2, the tightening strength of various joints can be further increased.

It is sectional drawing of the hollow tube for greenhouses which concerns on this invention. It is a figure which shows the joining structure which joined the hollow tubes for greenhouses which concern on this invention in the cross shape, the left is a front view, and the right is a side view. It is a perspective view which shows the joining structure of the arch member which consists of a pair of hollow curved pipe, and the hollow straight pipe of a ridge direction. It is a figure which shows the joining structure which joined the hollow tube for greenhouses and the film receiving member which concern on this invention to the cross shape, the left is a front view, and the right is a side view. It is a perspective view of the framework of the greenhouse constructed by assembling the greenhouse hollow tube according to the present invention. It is a figure which shows the joining structure which joined the hexagon hollow tube for greenhouses in the cross shape, the left is a front view, and the right is a side view.

FIG. 1 shows a cross-sectional shape of an octagonal empty tube according to the present invention.
In order to increase the contact area between pipes when joining polygonal pipes, such as a cross, each cross-section has a quadrilateral, hexagonal, octagonal, dodecagonal, or dodecagonal shape. However, of these, the rectangular cross section has the largest contact area and can increase the tightening strength. On the other hand, it is difficult to produce a stable hollow curved tube that is easily damaged during bending.

When the cross section of the hexagonal cross section is cross-joined, as shown in FIG. 6, the upper tube 1 and the lower tube 2 are in contact with each other while the flat portions are in surface contact with each other. The number of contact surfaces between the cross joint 3 and the inner surface of the winding portion 31 of the cross joint 3 is 3, and the edge of the receiving portion 32 corresponding to the hexagonal hollow tube formed on both sides of the cross joint 3 is inserted there. The number of contact portions with the other tube 2 is 2 on the front and back sides.
This is because the lower surface of one tube 1 is located below the upper edge 321 of the receiving portion 32 of the cross joint 3 and the two do not contact each other.

For this reason, when a hollow tube having a hexagonal cross section is cross-joined, a large contact surface between the tubes can be secured, while the hollow tube restraining force of the cross joint itself restraining the hollow tube by the cross joint is reduced.
In order to cope with this, it is necessary to increase the thickness of the steel material of the cross joint, and there arises a problem that the manufacturing cost increases.
Furthermore, the one with a dodecagonal cross section is difficult to adopt because the contact area between the hollow pipes is conspicuously limited compared to the hollow pipe with a hexagonal cross section.

On the other hand, when cross-jointing hollow tubes having an octagonal cross section, as shown in FIG. 2, the cross-section of one tube 1 and the cross joint 3 can be secured while ensuring a reasonably large contact surface between the tubes. The number of contact surfaces with the inner surface of the portal-shaped winding portion 31 is 5, especially the vertical surface of the hollow tube 1 is constrained, and the receiving portion corresponding to the octagonal hollow tube 2 formed on both sides of the cross joint 3 The number of contact portions between the 32 edges and the hollow straight pipe 2 inserted therethrough is 4 on each side.
That is, the contact area between the hollow tubes 1 and 2 and the hollow tube restraining force of the cross joint 3 itself are ensured in a well-balanced manner.
Therefore, the present invention employs a hollow tube having an octagonal cross section.

  This hollow tube for a greenhouse is a ridge direction member of a greenhouse, and a straight straight octagonal hollow straight tube over the entire length direction, an eave portion and a roof portion are straight, and an intermediate portion is an arc. It is composed of a combination with a curved curved tube having an octagonal cross section.

The pair of hollow bending tubes are formed in a substantially horseshoe-shaped arch member 4, as shown in FIG. It is.
The outer surface 12 and the inner surface 11 of the arch member 4, that is, the curved outer surface located on the outermost side of the curved portion of the hollow curved tube and the curved inner surface located on the innermost side are flat surfaces. There is no inner surface.
With this configuration, the joint portion between the hollow curved pipe 1 constituting a large number of arch members 4 built at intervals in the ridge direction and the hollow straight pipe 2 disposed in the ridge direction is flat on each pipe. The parts face each other and directly contact each other, and a large contact area is ensured.

FIG. 2 shows a joint structure of the cross joint 3 of the hollow bending tube 1 and the hollow straight tube 2 which are constituent members of the arch member.
The left side of FIG. 2 is a front view of the cruciform joint structure as seen from the surface of the greenhouse. The right side of the figure is a side view thereof.

  This cruciform joint 3 is obtained by changing a conventionally known cruciform joint for a hollow round tube to an octagonal hollow tube. The cross-jointed portal 31 of the cross joint 3 is applied to the hollow curved tube 1 to The hollow straight tube 2 is inserted into the receiving portion 32 corresponding to the octagonal hollow tube formed on both sides, and the wedge member 34 is driven into the engagement piece 33 formed at the lower part of the cross joint, thereby forming the hollow straight tube 2 as described above. The hollow curved tube 1 was tightened.

As is apparent from these drawings, the flat portions of the respective octagonal hollow tubes according to the present invention are in contact with each other.
For this reason, the hollow tube for greenhouses of the present invention can secure a much larger contact area than the contact area of point contact when the conventional hollow round tubes are joined to each other, thereby obtaining a strong tightening strength. ing.

  The cross joint 3 shown in FIG. 3 includes straight portions such as a roof portion, an eave portion, and a skirt portion of the arch member 4 in which the hollow curved tube 1 of the greenhouse shown in FIG. It is used as a fastening metal fitting at the intersection of the hollow straight pipe 2.

The cross joint shown in FIG. 3 is a cross joint 3 in a greenhouse ridge.
Reference numeral 41 denotes a connecting pipe in which the upper ends of the hollow curved tube 1 having an octagonal cross section are inserted into both end portions thereof and both are connected in the axial direction to form an arch-shaped arch member 4 as a whole.
Since the connecting pipe 41 is one in which the octagonal hollow bending tube 1 is inserted at both ends, the cross-sectional shape is naturally a hollow octagon over the entire length.

Further, the central portion 42 of the connecting pipe 41 is linear in the horizontal direction in order to increase the contact area between the connecting pipe 41 and the hollow straight pipe 2 and between the connecting pipe 41 and the cross joint 3.
Accordingly, the flat portions of the lower surface of the connection pipe 41 and the upper surface of the hollow straight pipe 2 are opposed to each other, and the flat portions of the upper surface of the connection pipe 41 and the inner surface of the cross joint 3 are opposed to each other. The three members are in direct surface contact with each other when tightening by means of the above, and the tightening strength of the crossing portion in the ridge portion is strengthened in the same manner as other cross joint portions.

On the other hand, in a greenhouse, the surface of a framework is often covered with a synthetic resin coating material such as a vinyl film.
FIG. 4 shows a film receiving member fixing device 6 for fixing a film receiving member 5 having a dovetail groove for covering the synthetic resin coating material to an arch member 4 having an octagonal cross section.

The film receiving member fixing device 6 includes a winding portion 61 having a U-shaped cross section for receiving the hollow bending tube 1 and a wedge 62 for pressing the hollow bending tube 1 against the bottom surface of the film receiving member 5.
Further, the upper end portion is provided with a locking portion that receives the film receiving member 5 and locks the oblique outer wall thereof, and presses the film receiving member 5 and the hollow bending tube 1 in cooperation with the wedge 62.

Since the bottom surface of the film receiving member 5 is a flat portion, the film receiving member 5 is in direct contact with the flat portion of the curved outer surface 11 of the hollow bending tube 1 to ensure a strong tightening force.
Thus, since the hollow curved tube 1 and the hollow straight tube 2 are formed into octagonal hollow tubes, and the groove shape of the film receiving member 5 is dovetail shape, the cross joint 3 or the film receiving member fixing device 6 is used. Since the flat surfaces are tightened by contacting the flat surfaces, surface contact over a wide area can be obtained, and a strong tightening force can be ensured.
In particular, it will be understood that the cruciform joint between the hollow tubes of the octagonal cross section of the present invention is remarkably strengthened as described above compared to the tightening force of the hollow tubes of the circular cross section.

  Further, if the friction coefficient is increased by forming a rough surface on the entire surface or joint portion of the hollow curved tube 1 and the hollow straight tube 2, the hollow tube having an octagonal cross section can be obtained. The tightening force between the cross joints is further increased.

DESCRIPTION OF SYMBOLS 1 Hollow curved pipe 11 Pipe inner surface 12 Pipe outer surface 2 Hollow straight pipe 3 Cross joint 4 Arch member 41 Connection pipe 42 Straight part 5 Film receiving member 6 Film receiving member fixing device

Claims (2)

A straight straight octagonal hollow straight tube over the entire length direction, a straight eave portion at one end and a substantially roof portion at the other end, and a curved portion whose middle portion is curved in an arc shape A hollow tube for greenhouse consisting of a combination of an octagonal hollow curved tube,
The hollow hollow tube for greenhouses, wherein a curved outer surface located on the outermost side of the bending portion and a curved inner surface located on the innermost side are flat surfaces.   2. The greenhouse hollow tube according to claim 1, wherein a surface of at least a part of the hollow curved tube and the hollow straight tube is roughened to increase a coefficient of friction.