JP2019115980A - Manufacturing method of cover, molded form and molding die - Google Patents

Abstract

To provide a manufacturing method of a cover, molded form and molding die which can suppress cost increase for the production of a cover by blow molding.SOLUTION: A manufacturing method of a cover is made up of two steps. The first step is to produce a molded form 100 by blow molding, including a first cover part 102 and a second cover part 104, which are used for a cover, and a first cut-off part 103, which is in contact with the first cover part 102 and the second cover part 104. The second step is to cut the molded form 100 and detach the first cover part 102, the first cut-off part 103 and the second cover part 104.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a method of manufacturing a cover, a molded article, and a mold for molding.

  There is a bed apparatus such as a stretcher having a lifting function for moving up and down a bed unit, and as the lifting apparatus, for example, an actuator such as a hydraulic cylinder may be used. Moreover, the structure which provides a cover around a hydraulic cylinder is also known as a raising / lowering apparatus. The cover prevents the body fluid and dust from adhering to the hydraulic cylinder, and also prevents the user from touching the sliding portion of the hydraulic cylinder. In addition, this cover also has the effect of improving the appearance, such as providing a sense of solidity and a sense of security due to the size by covering the hydraulic cylinder with the cover. As one of such covers, a telescopic cover that expands and contracts according to the expansion and contraction of a hydraulic cylinder is known.

  The telescopic cover is formed, for example, by concentrically combining a plurality of substantially cylindrical covers having different diameters. Then, the entire length can be changed by pulling out the small diameter cover from the large diameter cover or housing the small diameter cover in the large diameter cover. The plurality of covers used for the telescopic cover are individually formed, for example, by vacuum forming a sheet formed of a thermoplastic resin material.

JP, 2015-159944, A

  However, since vacuum forming is performed by vacuuming a sheet to form a formed product, it is difficult to increase the thickness of the formed product, that is, the thickness (thickness) of the cover, as compared to, for example, blow molding. In the case where the thickness of the cover is thin, defects, breakage and the like due to insufficient strength tend to occur. For this reason, there is a possibility that the manufacturing cost of the cover may increase due to the decrease in yield. In addition, if the cover is damaged after the bed apparatus attached with the cover is shipped, maintenance costs such as replacement of the cover may occur.

  Comparing vacuum molding and blow molding, for example, when the molded product by vacuum molding has a cylindrical shape, the thickness is often thin, but the thickness of the molded product by blow molding can be easily adjusted. , Can be as thick as required. In addition, when forming a substantially cylindrical molded article by vacuum molding, the molded article is formed with a line based on the parting line (PL) of the mold surrounding the outer periphery in the radial direction. On the other hand, in a blow-molded article, a line based on the parting line is formed to surround the outer periphery in the axial direction. Also, in the case of vacuum forming, it is necessary to provide a draft in the mold, and the molded product has a shape based on the draft of the mold. On the other hand, in the case of blow molding, it is not necessary to provide a draft in the mold, and a molded article having no shape based on the draft of the mold may be molded. Further, in the vacuum forming, the surface of the molded product loses the wrinkled pattern due to the sheet material molding with the wrinkled pattern (embossed pattern), and the transferability is poor even if the wrinkled pattern (grained texture) is attached to the mold. On the other hand, in blow molding, it is easier to emboss the surface of a molded article than in vacuum molding.

  This invention is made in view of the above-mentioned subject, Comprising: In manufacture of the cover using blow molding, the manufacturing method of a cover which can suppress the increase in manufacturing cost, a molded article, and the metal mold | die for shaping | molding are provided. The purpose is to

  According to the present invention, a method of manufacturing a cover comprises blow molding a molded article having a first cover portion and a second cover portion used for the cover, and a first cutting portion contacting the first cover portion and the second cover portion. And a step of cutting the molded product to separate the first cover portion, the first cutout portion, and the second cover portion.

  Further, according to the present invention, the method of manufacturing the cover can further include the step of combining the separated first and second cover portions.

  Further, according to the present invention, the method of manufacturing the cover can further include the step of separating the first cover portion from the second cutting portion in contact with the first cover portion, and the first cover portion and the second cutting portion And the outer diameter of the first opening of the first cover formed by separating the second cover from the outer diameter of the second opening of the second cover formed by separating the second cover and the first cutout. The outer diameter of the second opening is larger than the inner diameter of the third opening of the first cover formed by separating the first cover and the first cutout.

  Further, according to the present invention, the cover can be used for a bed apparatus provided with a pedestal, an elevating device, and a bed unit.

  Further, according to the present invention, the molded product is in contact with the first cover portion, the second cover portion, the first cutting portion in contact with the first cover portion and the second cover portion, and the first cover portion, A second cutting portion separated from the cover portion, and a third cutting portion in contact with the second cover portion and separated from the first cover portion, the first cutting portion separating the first cover portion from the second cutting portion The outer diameter of the first cut position is larger than the outer diameter of the second cut position where the second cover portion and the first cut portion are separated, and the outer diameter of the second cut position is the first cover portion and the first cut portion The outer diameter of the third cutting position is larger than the outer diameter of the third cutting position where the second cover portion and the third cutting portion are separated.

  Further, according to the present invention, the first cover part separated from the first and second cutout parts, and the second cover part separated from the second and third cutout parts are combined to form a cover. Used for

  Further, according to the present invention, the first cover portion and the second cover portion have parting lines.

  Further, according to the present invention, the mold for molding includes the first cover, the second cover, the first cutout contacting the first cover and the second cover, and the second cover contacting the first cover. And a cavity having a shape corresponding to a third cutout spaced from the first cover portion and in contact with the second cover portion. At this time, in the cavity, the inner diameter at the first position where the first cover portion and the second cutout contact each other is larger than the inner diameter at the second position where the second cover portion and the first cutout contact each other. The inner diameter is larger than the inner diameter at the third position where the first cover portion and the first cutout contact, and the inner diameter at the third position is larger than the inner diameter at the fourth position where the second cover and the third cutout contact. large.

  Further, according to the present invention, in the molded article molded using the mold, the first cover portion, the second cover portion, the first cutout portion, the second cutout portion, and the third cutout portion are respectively separated.

  According to the present invention, an increase in manufacturing cost can be suppressed in the manufacture of a cover using blow molding.

FIG. 1 is a perspective view of a stretcher provided with a cover according to the first embodiment. FIG. 2 is a side view of the stretcher at the highest position and the lowest position of the stretcher provided with the cover according to the first embodiment. FIG. 3 is a cross-sectional view of a support provided with the cover according to the first embodiment. FIG. 4 is a view showing the side surface and the cross section of the cover according to the first embodiment in the most extended state. FIG. 5 is a cross-sectional view of the first cover, the second cover, and the third cover according to the first embodiment. FIG. 6 is a flowchart showing a method of manufacturing a support in the stretcher including the cover according to the first embodiment. FIG. 7: is a figure which shows the upper surface and side surface of the molded article which concern on 1st Embodiment. FIG. 8 is a cross-sectional view of the molded article according to the first embodiment. FIG. 9 is a cross-sectional view of a molded article in which the area AR in FIG. 8 is enlarged. FIG. 10 is a cross-sectional view of a molding die according to the first embodiment. FIG. 11 is a flowchart showing the method of manufacturing the cover according to the first embodiment. FIG. 12 is an enlarged view of a part of the cross section of the molded article according to the second embodiment.

    Embodiments will be described below with reference to the drawings. In the description, common parts are given the same reference numerals throughout the drawings.

1. First Embodiment A method of manufacturing a cover, a molded product, and a mold for molding according to the first embodiment will be described. Below, the example which used the telescopic cover for the hydraulic cylinder of the raising / lowering apparatus of the stretcher which has a raising / lowering function is demonstrated. Note that the telescopic cover is not limited to a stretcher, and may be applied to other bed devices having an elevating function such as a medical bed, a care bed, an operating table, a bed for a newborn baby, etc. The invention may be applied to products having an elevating function such as

1.1 Configuration of Stretcher First, the overall configuration of the stretcher 1 will be described using FIGS. 1 and 2. FIG. 1 shows a perspective view of the stretcher 1. FIG. 2 is a view showing the lifting and lowering operation of the stretcher 1, in which the middle floor 2 (bed section) of the stretcher 1 is most raised (hereinafter referred to as “highest position”) and the inside of the stretcher 1 The side of the stretcher 1 is shown in a state in which the floor 2 is most lowered (hereinafter referred to as "lowest"). In the following description, a person (for example, a patient) who supine (or hesitates) on the stretcher 1 is called a "user", and a person who operates the stretcher 1 is called an "operator". The user's foot side was called the "foot side" of the stretcher 1 with the stretcher 1 supposing the user, and the head side of the user was called the "head side" of the stretcher 1 and supine The right and left sides of the user are referred to as the “right side” and “left side” of the stretcher 1, respectively. Moreover, since the stretcher 1 has a structure long in the direction connecting the head side and the foot side and short on the left and right, the direction connecting the head side and the foot side of the stretcher 1 is referred to as “longitudinal direction”. The left and right direction of is referred to as Furthermore, in the stretcher 1, the direction perpendicular to the ground is referred to as “vertical direction”.

  As shown in FIG. 1, the stretcher 1 includes, for example, an inner floor 2, a carriage (base) 3, two columns 4, and a mattress 5. The number of supports 4 in the stretcher 1 is not limited to two. For example, the support 4 may be one. When the support 4 is one, the support 4 may have a mechanism for tilting the midbed 2 in the longitudinal direction or the lateral direction. Furthermore, three or more support columns 4 may be provided.

  The mattress 5 is arranged on the mid-floor 2, on which the user, for example, lies.

  The mid floor 2 includes a main frame 6, a back bottom 7, knee bottoms 8, foot bottoms 9, a transfer board 10, a transfer handle 11, a back lift lever 12, a knee lift handle 13, and a corner bumper 14.

  The main frame 6 is a component serving as a framework of the mid floor 2. The main frame 6 is provided with two rod receptacles not shown. The rod receiver is fixed to a frame extending in the lateral direction of the main frame 6 vertically penetrating the frame. One post 4 is fixed to one rod holder. Also, back bottom 7, knee bottom 8, foot bottom 9, transfer board 10, transfer handle 11, back raising lever 12, knee raising handle 13, and four corner bumpers 14 are attached to main frame 6.

  The back bottom 7, the knee bottom 8 and the foot bottom 9 are installed on the top of the main frame 6 and support the mattress 5.

  The back bottom 7 supports the upper body (head, back, etc.) of the user. The back bottom 7 has a back-raising function. The back-raising function is a function of raising the head side of the back bottom 7 and raising the upper body of the user.

  The lifting lever 12 is configured to be operable by the operator, for example. The lifting lever 12 is installed on the head side of the main frame 6 so as to be able to be pulled up. While the spine lifting lever 12 is being pulled up by the operator, the spine bottom can be pulled up or down. The back raising lever 12 is configured to be returned to a lowered position from a position where the back raising lever 12 is pulled up by a spring (not shown). When the spine lifting lever 12 is pulled down, the spine bottom 7 is fixed at that position.

  The knee bottom 8 and the foot bottom 9 support the lower part from the buttocks of the user. The knee bottom 8 and the foot bottom 9 have a knee lifting function. The knee raising function is a function of raising the foot side of the knee bottom 8 and the head side of the foot bottom 9 to bend the user's foot and lift the knee.

  The knee lifting handle 13 is configured to be operable by an operator by hand, for example. The knee lifting handle 13 is rotatably installed on the foot side of the main frame 6. By turning the knee lifting handle 13, the user can perform knee lifting or knee lifting operation.

  The transfer board 10 is installed on the right and left sides of the main frame 6. The transfer board 10 is inclinable, and includes a lock mechanism that fixes the position of the transfer board 10. The locking mechanism fixes the position of the transfer board 10 when it is locked when the transfer board 10 is in the horizontal position or the pulled up position. Also, the lock mechanism is unlocked when the transfer board 10 is pulled down. For example, when the transfer board 10 is used to prevent the user from falling, the transfer board 10 is fixed at the pulled up position. In addition, when the user gets on / off from the side of the stretcher 1, the transfer board 10 is put down. In addition, when the transfer board 10 is used as an upper arm support, the transfer board 10 is fixed at the horizontal position.

  The transport handle 11 is installed on the head side of the main frame 6 and is used when the operator moves the stretcher 1. The transport handle 11 is, for example, a foldable type, and when moving the stretcher 1, the transport handle 11 is pulled up and used.

  Four corner bumpers 14 are installed at the four corners of the main frame 6. The corner bumpers 14 reduce the impact when the stretcher 1 collides with a wall or the like.

  The carriage 3 includes a carriage cover 15, a moving device, and a lifting device.

  The dolly cover 15 is installed on a dolly frame (not shown) of the dolly 3 for the purpose of preventing adhesion of body fluid, dust and the like of the user to the dolly 3 and contact prevention of the user and the operator.

  The moving device includes four casters 16, a caster operation pedal 17, and a center wheel (not shown).

  Four casters 16 are provided at the four corners of the carriage 3. The caster 16 has a wheel, an axle, and a lock mechanism that locks the rotation of the wheel and the rotation of the axle. The wheels of the caster 16 are rotatably supported on the axle of the caster 16. The axles of the casters 16 are rotatably supported by the carriage 3. The lock mechanism switches locking and unlocking of the rotation of the wheels and axles of the caster 16 by the operation of the caster operating pedal 17.

  The center wheel is provided at the center of the carriage 3. The center wheel includes a wheel, an axle, and a lifting mechanism for lifting and lowering the wheel. The wheels of the center wheel are longitudinally rotatably supported on the axle of the center wheel. The axle of the center wheel is supported by the carriage 3 so as to be tiltable in the longitudinal direction. For example, the lifting mechanism of the center wheel switches the axle between the horizontal position and the inclined position by the operation of the caster operation pedal 17. When the center wheel axle is in the horizontal position, the wheels are housed within the bogie frame and do not touch the ground. When the center wheel axle is in the inclined position, one end of the axle supporting the wheel is lowered, and the wheel contacts the ground. By grounding the wheels of the center wheel, the straightness and turning of the stretcher 1 are improved, and the travel of the stretcher 1 is stabilized.

  For example, the caster operation pedal 17 is configured to be operable by the operator with his / her hands and feet. The caster operation pedal 17 is an operation means used for operating the lock mechanism of the caster 16 and the elevation mechanism of the center wheel. The caster operation pedals are provided at four corners of the carriage 3 and above the casters 16 respectively. The four caster operation pedals 17 are interlocked, and by operating any one of the caster operation pedals 17, the other three caster operation pedals 17 perform the same operation. The caster operation pedal 17 has a structure that can be folded in the longitudinal direction. The caster control pedal 17 has three settings: a horizontal first position, a second position at the head side, and a third position at the foot side. For example, in the first position, the wheels of the center wheel are not grounded, and the wheels and axles of the four casters 16 are not locked. In the second position, the wheels of the center wheel are grounded and the wheels and axles of the four casters 16 are not locked. Also, in the third position, the wheels of the center wheel are not grounded, and the wheels and axles of the four casters 16 are locked.

  The lifting device is used to lift and lower the mid floor 2 of the stretcher 1. The lifting device comprises a lift pedal 18, a foot pedal 19, a head pedal 20, a down pedal 21 and two hydraulic cylinders 22.

  The hydraulic cylinder 22 comprises a cylinder 31 and a piston rod 32. The cylinder 31 and the piston rod 32 support the middle floor 2 as a support 4. A hydraulic cylinder 22 on the head side and a hydraulic cylinder 22 on the foot side are respectively provided corresponding to the column 4 on the head side and the foot side. The hydraulic cylinder 22 on the head side and the hydraulic cylinder 22 on the foot side have the same structure. As the hydraulic cylinder 22 expands and contracts, the support 4 expands and contracts, and the mid floor 2 moves up and down.

  The raising pedals 18 are provided on the right and left sides of the carriage 3 and are configured to be operable by an operator, for example, by the hands and feet. The raising pedal 18 raises the hydraulic pressures of the two hydraulic cylinders 22 and extends the two hydraulic cylinders 22 by a depression operation. When the raising pedal 18 is depressed, it is returned upward by a spring (not shown), and can be repeatedly depressed. The lift pedal 18 is an operating means for extending the two hydraulic cylinders 22.

  The foot pedal 19 is provided on the right side and the left side of the carriage 3 and is configured to be operable by the operator using his / her hands and feet, for example. During the depressing operation, the toe pedal 19 reduces the hydraulic pressure of the hydraulic cylinder 22 on the foot side and contracts the hydraulic cylinder 22 on the foot side. The foot pedal 19 is configured to return upward by a spring (not shown) when depressed. The foot pedal 19 is an operating means for contracting the hydraulic cylinder 22 on the foot side.

  The head-carried pedal 20 is provided on the right and left sides of the carriage 3 and is configured to be operable by an operator, for example. During the depressing operation, the head-lifting pedal 20 reduces the hydraulic pressure of the hydraulic cylinder 22 on the head side, and contracts the hydraulic cylinder 22 on the head side. The head-lifting pedal 20 is configured to return upward by a spring (not shown) when depressed. The head lift pedal 20 is an operating means for contracting the hydraulic cylinder 22 on the head side.

  The lowering pedal 21 is provided on the foot side of the carriage 3 and, for example, the operator can be operated by the hands and feet. The lowering pedal 21 reduces the hydraulic pressure of the two hydraulic cylinders 22 during the depressing operation, and contracts the two hydraulic cylinders 22. The down pedal 21 is configured to return upward by a spring (not shown) when depressed. The lowering pedal 21 is an operating means for contracting the two hydraulic cylinders 22.

  As shown in FIG. 2, in the lifting device, when the lift pedal 18 is operated to extend the two hydraulic cylinders 22, the two columns 4 extend and the mid-floor 2 rises. Also, with the two hydraulic cylinders 22 extended, operating the foot pedal 19 and the head pedal 20 or operating the down pedal 21 to retract the two hydraulic cylinders 22 causes the two columns 4 to The inner floor 2 descends by contracting.

  Further, in the lifting device, when the two hydraulic cylinders 22 are extended, the head side lifting pedal 20 is operated to contract the head side hydraulic cylinder 22, the head side support 4 contracts and the foot side support 4 Is extended and the head side of the midbed 2 is lowered. Such a state is called "Trendenburg".

  In the lifting device, when the two hydraulic cylinders 22 are extended, the foot pedal 19 is operated to contract the hydraulic cylinders 22 on the foot side, the head side pillars 4 are extended and the foot side columns 4 are extended. Is in a contracted state, and the foot side of the middle floor 2 is lowered. Such a state is called "Riverstran Derenberg".

  In addition, although the case where hydraulic cylinder 22 was used for a raising / lowering apparatus was demonstrated, it is not limited to hydraulic cylinder 22. FIG. It may be an air cylinder or an electric actuator. Furthermore, although the manual (foot-operated) hydraulic cylinder 22 has been described, it may be an electric hydraulic cylinder 22.

  Next, the configuration of the support 4 will be described with reference to FIG. FIG. 3 shows a cross-sectional view of the head side strut 4 cut along the longitudinal direction. In addition, the support | pillar 4 of the foot side is also the same structure.

  As shown in FIG. 3, the support 4 includes a cylinder 31 and a piston rod 32 of a hydraulic cylinder 22, a telescopic cover 23, and an upper lid 36.

  The cylinder 31 is fixed, for example, to a frame 39 extending in the lateral direction of the carriage frame using a mounting bracket 40.

  The piston rod 32 is moved in and out of the cylinder 31 in accordance with the hydraulic pressure of the hydraulic cylinder 22 and moves on a straight line in the vertical direction. The upper end of the piston rod 32 is fixed to a rod receiver 37 of the main frame 6.

  The upper lid 36 is disposed above the frame 38 extending in the lateral direction of the main frame 6 and covers a portion of the frame 38 and the rod receiver 37 fixed to the frame 38. The upper lid 36 sandwiches the frame 38 together with the first cover 33 of the telescopic cover 23. For example, a clip (not shown) or the like is attached to the screw hole 41 of the first cover 33 and the screw hole 42 of the upper lid 36, and the upper lid 36 is attached to the first cover 33. The first cover 33 and the upper lid 36 are fixed to the main frame 6 by sandwiching the frame 38 and move up and down together with the middle floor 2. Further, the upper lid 36 prevents the user's body fluid, dust and the like from entering the telescopic cover 23.

  The telescopic cover 23 has a three-tiered configuration including a first cover 33, a second cover 34, and a third cover 35 having different diameters. The number of stages of the telescopic cover 23 may be two or more. The second cover 34 is disposed inside the first cover 33, the third cover 35 is disposed inside the second cover 34, and the cylinder 31 is disposed inside the first cover 33, the second cover 34, and the third cover 35. And the piston rod 32 is passed through.

  Next, the configuration of the telescopic cover 23 will be described in detail with reference to FIGS. 4 and 5. FIG. 4 shows the configuration of the telescopic cover 23 in the most extended state in a partial cross section. In the example of FIG. 4, the left half of the drawing shows the side surface of the telescopic cover 23, and the right half of the drawing shows the cross section of the telescopic cover 23. FIG. 5 shows a cross-sectional view of the first cover 33, the second cover 34, and the third cover 35. As shown in FIG. In the following description, the large diameter end of each cover is referred to as "one end" and the small diameter end is referred to as "the other end".

  As shown in FIG. 4, each of the first cover 33, the second cover 34, and the third cover 35 has a conical tubular shape having an outer diameter at one end larger than the outer diameter at the other end. The first cover 33, the second cover 34, and the third cover 35 may have a polygonal tubular shape. The thicknesses of the first cover 33, the second cover 34, and the third cover 35 are substantially the same.

  As shown in FIG. 5, the first cover 33 has an inner flange 50 that gradually decreases in diameter from one end to the other end and radially and annularly protrudes on the inner peripheral surface of the other end. The inner diameter of the opening of the inner flange 50 is smaller than the inner diameter of the first cover 33. In the first cover 33, an attachment portion 43 of a substantially tetrahedron having two screw holes 41 at two positions symmetrical in the radial direction on one end side of the first cover 33 protrudes from the outer peripheral surface It is provided.

  The second cover 34 has an outer diameter smaller than the inner diameter of the first cover 33, and the inner diameter gradually decreases from one end to the other end. The second cover 34 has an outer flange 51 and an inner flange 52. The outer flange 51 is provided at one end of the second cover 34, and has an annular shape formed to have an outer diameter smaller than the inner diameter of the first cover 33 and larger than the inner diameter of the inner flange 50 of the first cover 33. Have. The inner flange 52 is provided at the other end of the second cover 34, has an inner diameter smaller than the inner diameter of the second cover 34, and has a shape projecting radially in an annular manner on the inner peripheral surface of the other end.

  The third cover 35 has an outer diameter smaller than the inner diameter of the second cover 34, and the inner diameter gradually decreases from one end to the other end. The third cover 35 has an outer flange 53 and an inner flange 54. The outer flange 53 is provided at one end of the third cover 35, and has an annular shape formed to have an outer diameter smaller than the inner diameter of the second cover 34 and larger than the inner diameter of the inner flange 52 of the second cover 34. Have. The inner flange 54 is provided at the other end of the third cover 35, has an inner diameter smaller than the inner diameter of the third cover 35, and has a shape projecting radially in an annular manner on the inner peripheral surface of the other end. Further, the inner flange 54 is larger than the outer diameter of the cylinder 31 and suppresses backlash with the cylinder 31. The inner flange 54 may be discarded.

  The extension operation of the telescopic cover 23 will be briefly described. As the hydraulic cylinder 22 extends, the first cover 33 ascends with the middle floor 2. At this time, the second cover 34 is pulled out from the other end of the first cover 33 by its own weight, but when the outer flange 51 of the second cover 34 is hooked on the inner flange 50 of the first cover 33 The second cover 34 ascends together. Furthermore, when the second cover rises, the third cover 35 is pulled out from the other end of the second cover 34 by its own weight, but when the outer flange 53 of the third cover 35 is hooked on the inner flange 52 of the second cover 34 , And the third cover 35 together with the second cover 34.

  Next, the inner diameters of one end and the other end of the first cover 33, the second cover 34, and the third cover 35 will be described in detail. In the following description, the inner diameter of one end of the first cover 33 is W1, and the inner diameter of the inner flange 50 is W2. The inner diameter of the outer flange 51 of the second cover 34 is W3 and the inner diameter of the inner flange 52 is W4. The inner diameter of the outer flange 53 of the third cover 35 is W5, and the inner diameter of the inner flange 54 is W6.

  From the relationship of the first cover 33, the second cover 34, and the third cover 35 described above, the inner diameter W3 of the outer flange 51 of the second cover 34 is smaller than the inner diameter W1 of one end of the first cover 33, It is larger than the inner diameter W2 of the flange 50. Similarly, the inner diameter W5 of the outer flange 53 of the third cover 35 is smaller than the inner diameter W3 of the outer flange 51 of the second cover 34 and larger than the inner diameter W4 of the inner flange 54. Further, the inner diameter W5 of the outer flange 53 of the third cover 35 is smaller than the inner diameter W2 of the inner flange of the first cover 33 and larger than the inner diameter W6 of the inner flange 54 of the third cover 35. Therefore, the inner diameters W1 and W2 of the first cover 33, the inner diameters W3 and W4 of the second cover 34, and the inner diameters W5 and W6 of the third cover 35 have a relationship of W1> W3> W2> W5> W4> W6.

  In the example of FIG. 4, the other end of the first cover 33 is provided with the inner flange 50, the other end of the second cover 34 is provided with the inner flange 52, and the other end of the third cover 35 is provided with the inner flange 54. Although the case where it is provided has been described, it may not be provided at the other end of each cover, as long as it is provided near the other end. Similarly, although the case where the outer flange 51 is provided at one end of the second cover 34 and the outer flange 53 is provided at one end of the third cover 35 has been described, it may not be provided at one end of each cover , And may be provided in the vicinity of one end.

1.2 Method of Producing Struts Next, a method of producing the struts 4 in the stretcher 1 will be described with reference to FIG. FIG. 6 is a flowchart showing a method of manufacturing the support 4.

  As shown in FIG. 6, first, the hydraulic cylinder 22 is attached to the carriage 3 (step S1). More specifically, the lifting device is installed on the carriage 3. At this time, the mounting fitting 40 is used to fix the cylinder 31 of the hydraulic cylinder 22 to the frame 39 of the carriage frame.

  Next, the hydraulic cylinder 22 is disposed inside the telescopic cover 23 (step S2). More specifically, the hydraulic cylinder 22 is passed through the first cover 33, the second cover 34, and the third cover 35 in a state where the first cover 33, the second cover 34, and the third cover 35 are combined.

  Next, the upper part of the hydraulic cylinder 22 is attached to the middle floor 2 (step S3). More specifically, for example, the piston rod 32 of the hydraulic cylinder 22 is inserted from below into a rod receiver 37 attached to the frame 38 of the main frame 6, and fixed with a bolt or the like.

  Next, the upper cover 36 and the telescopic cover 23 are attached to the main frame 6 (step S4). More specifically, the rod receiver 37 and a part of the frame 38 are covered with the upper lid 36, and the upper lid 36 and the first cover 33 sandwich the frame 38. Next, the first cover 33 is attached to the upper lid 36. The upper cover 36 and the first cover 33 are fixed to the main frame 6 by sandwiching the frame 38. Thus, the support 4 is completed.

1.6 Structure of Molded Product of First to Third Covers Next, a structure of a molded product of the first cover 33, the second cover 34, and the third cover 35 will be described with reference to FIGS. In this embodiment, the case where one molded product including the first cover 33, the second cover 34, and the third cover 35 is molded by blow molding will be described. For molded articles, thermoplastic resins suitable for blow molding such as polystyrene (PS), polypropylene (PP), polyethylene (PE), low density polypropylene (LDPE), and ABS resin are used, for example. FIG. 7 shows a top view, a first side view, and a second side view of the molded article 100. FIG. 8 shows a cross-sectional view of the molded article 100 when cut along the second direction. FIG. 9 shows an enlarged view of a region AR near the second cutout portion 103 shown in FIG.

  In the following description, the end on the first cutout portion 101 side of the molded article 100 is referred to as “one end”, and the end on the fourth cutout portion 107 side is referred to as “the other end”. A view from one end of the molded article 100 is a top view. Let the direction which looked at attachment part 43 in the front be the 1st direction, and let the side seen from the 1st direction be the 1st side. Let the direction which looked at attachment part 43 from the side be the 2nd direction, and let the side seen from the 2nd direction be the 2nd side. Further, in FIG. 7, a position corresponding to PL (parting line) of the mold of the molded article 100 is indicated by a two-dot chain line. Moreover, in the example of FIG.8 and FIG.9, the cutting position of the molded article 100 is shown by the figure of a dashed-two dotted line and a blade (cutter).

  As shown in FIG. 7, the molded article 100 includes a first cutout 101, a first cover 102, a second cutout 103, a second cover 104, a third cutout 105, a third cover 106, and a third cover. 4 includes a cutting unit 107. In the molded article 100, the first cutaway portion 101, the first cover portion 102, the second cutaway portion 103, the second cover portion 104, the third cutaway portion 105, the third cover portion 106, and the fourth cutaway portion 107 are continuous. Provided. After being cut, the first cutaway portion 101, the second cutaway portion 103, the third cutaway portion 105, and the fourth cutaway portion 107 are melted again and, for example, reused for forming. The molded article 100 is a part of the first cutaway portion 101, the first cover portion 102, the second cutaway portion 103, the second cover portion 104, the third cutaway portion 105, the third cover portion 106, and the fourth cutaway portion 107. May have burrs based on PL of the mold. In other words, the first cutting portion 101, the first cover portion 102, the second cutting portion 103, the second cover portion 104, the third cutting portion 105, the third cover portion 106, and the fourth cutting portion 107 are molds. Have a PL based on

  The first cutout portion 101 is located at one end of the molded article 100 and in contact with one end of the first cover portion 102. For example, when air is blown from one end of the molded article 100 in blow molding, an air blowing port may be formed in the first cutout portion 101.

  The first cover portion 102 corresponds to the first cover 33. The other end of the first cover portion 102 is in contact with one end of the second cutout portion 103. The first cover 33 is formed by separating the first cover portion 102 from the first cutout portion 101 and the second cutout portion 103.

  The second cover portion 104 is a portion corresponding to the second cover 34. One end of the second cover portion 104 is in contact with the other end of the second cutout portion 103, and the other end of the second cover portion 104 is in contact with one end of the third cutout portion 105. The second cover 34 is formed by separating the second cover portion 104 from the second cutout portion 103 and the third cutout portion 105.

  The third cover portion 106 corresponds to the third cover 35. One end of the third cover 106 is in contact with the other end of the third cutout 105, and the other end of the third cover 106 is in contact with one end of the fourth cutout 107. The third cover 35 is formed by separating the third cover portion 106 from the third cutout portion 105 and the fourth cutout portion 107.

  The fourth cutout 107 is located at the other end of the molded article 100. In addition, for example, when air is blown in from the other end of the molded article 100 in blow forming, an air blowing port may be formed in the fourth cutout portion 107.

  In the example of FIG. 7, the mold of the molded article 100 surrounds the outer periphery in the axial direction of the molded article 100, and PL is provided at a position where the mounting portion 43 is a target in the radial direction. The mold PL can be set arbitrarily.

  Next, the cross-sectional shape and the cutting position of the molded article 100 will be described.

  As shown in FIG. 8, when the molded article 100 is cut to form the first cover 33, the second cover 34, and the third cover 35, six cutting positions are provided. The molded product 100 is cut with a cutter at a cutting position indicated by a two-dot chain line, and the first cover 33, the second cover 34, and the third cover 35 are formed. In the following description, the cutting position of the first cutting portion 101 and the first cover portion 102, that is, the cutting position corresponding to one end of the first cover 33 is the first cutting position 111.

  As shown in FIG. 9, the cutting position of the first cover portion 102 and the second cutting portion 103, that is, the cutting position corresponding to the other end of the first cover 33 is the second cutting position 112. The cutting position of the second cutting portion 103 and the second cover portion 104, that is, the cutting position corresponding to one end of the second cover 34 is the third cutting position 113.

  Returning to FIG. 8, the cutting position of the second cover portion 104 and the third cutting portion 105, that is, the cutting position corresponding to the other end of the second cover 34 is the fourth cutting position 114. The cutting position of the third cutting portion and the third cover portion 106, that is, the cutting position corresponding to one end of the third cover 35 is the fifth cutting position 115. The cutting position of the third cover portion 106 and the fourth cutting portion 107, that is, the cutting position corresponding to the other end of the third cover 35 is the sixth cutting position 116.

  In the following description, assuming that the outer diameters of the molded product 100 at the first cutting position 111 to the sixth cutting position 116 are Wc1, Wc2, Wc3, Wc4, Wc5, and Wc6, respectively, from the relationship described in FIG. Wc1> Wc3> Wc2> Wc5> Wc4> Wc6.

1.7 Mold for Forming Next, a mold for forming 200 will be described with reference to FIG. FIG. 10 shows a cross-sectional view of a mold 200 having split molds 210 and 220. The example of FIG. 10 shows the case where air is blown from one end of the molded article 100. Further, a case where a portion corresponding to the screw hole 41 has a concave shape in the molded product 100 is shown. The portion corresponding to the screw hole 41 may have a convex shape in the molded article 100. Further, the PL of the mold 200 may be different from the PL position in the molded article 100 shown in FIG. 7. In this case, the shapes of the two split dies 210 and 220 may be different from each other.

  As shown in FIG. 10, the mold 200 includes two split molds 210 and 220. The mold 200 forms one molded article 100 with two divided molds 210 and 220. The split mold 210 includes a cavity 211, a blow port 212, and a biting portion 213. Similarly, the split mold 220 includes a cavity 221, a blow port 222, and a biting portion 223. The split molds 210 and 220 contact each other at the split surface along the PL during blow molding.

  The cavities 211 and 221 each have a concave shape corresponding to a part of the outer surface of the molded article 100. By combining the split molds 210 and 220 with the split surfaces, the shape produced by the cavities 211 and 221 is the cavity of the mold 200 and is a depression in the shape of the outer surface of the molded article 100. More specifically, the cavity of the mold 200 corresponds to the first cutaway portion 101, the first cover portion 102, the second cutaway portion 103, the second cover portion 104, the third cutaway portion 105, and the third cover of the molded article 100. It includes a concave shape corresponding to the outer surface of the portion 106 and the fourth cutout 107.

  The blow blow ports 212 and 222 were pressed against the softened tube-shaped thermoplastic resin material (hereinafter referred to as “parison”) in the mold 200 in a state where the split molds 210 and 220 are combined in the blow molding. Used when introducing air.

  The biting portions 213 and 223 cut the parison and press and seal the parison at the bottom in the cavities 211 and 221 when the split molds 210 and 220 are put together to pinch off the parison in blow molding.

1.5 Method of Manufacturing First to Third Covers Next, a method of manufacturing the first cover 33, the second cover 34, and the third cover 35 will be described with reference to FIG.

  As shown in FIG. 11, first, a molded article 100 including the first cover 33, the second cover 34, and the third cover 35 is molded by blow molding (step S11). In addition, the kind of blow molding is not limited. The following description demonstrates the case where a molded article is molded by direct blow. More specifically, first, the parison is extruded from the extruder. The extruded parison is pinched by the split molds 210 and 220 to perform clamping and at the same time pinch off one end of the parison to close it. Pressurized air is blown into the parison in the mold 200 to mold the molded article 100. Next, the split mold 210 and the split mold 220 are separated to separate the molded article 100 from the mold 200. Also, the molded article 100 may be separated from the mold 200 after being cooled by the mold 200, and may be cooled after being separated from the mold 200.

  Next, deburring of the molded article 100 is performed (step S12). Alternatively, the parison may be clamped with the division surfaces of the division molds 210 and 220 in the shape of a knife. Since the excess parison outside the cavities 211 and 212 is removed when the parison is clamped by forming it into a blade shape, the deburring process of step S12 is omitted.

  Next, the molded article 100 is cut, and the first cover 33, the second cover 34, and the third cover 35 are formed (step S13). The cutting of the molded article 100 may be manual work, or a dedicated jig or device may be used to enhance the alignment accuracy of the cut surface of the molded article 100. The manufacturer of the molded article 100 may ship the molded article 100 before the cutting operation of step S13, and the cutting operation may be performed by a customer (for example, a stretcher manufacturer) who has purchased the molded article 100.

  Next, the screw holes 41 are opened in the first cover 33 (step S14). More specifically, when the mold 200 shown in FIG. 10 is used, the portion corresponding to the screw hole 41 of the molded article 100 has a concave shape. Therefore, the screw hole 41 is formed by opening the recess with a drill. In addition, when the part corresponded to the screw hole 41 of the molded article 100 is made into convex shape, you may cut a convex part with a blade and may form the screw hole 41, for example. The order of steps S13 and S14 may be reversed.

  Next, the first cover 33, the second cover 34, and the third cover 35 are combined to form the telescopic cover 23 (step S15). The manufacturer of the molded article 100 ships the first cover 33, the second cover 34, and the third cover 35 before the assembling operation in step S15, and the assembling operation is performed by the first cover 33, the second cover 34, And customers who purchased the third cover 35 (e.g., a stretcher manufacturer). More specifically, for example, the cover assembly operation may be performed in the manufacturing process of the support 4 described in FIG.

1.8 Effects According to Present Embodiment With the configuration according to the present embodiment, it is possible to suppress an increase in the manufacturing cost of the cover by blow molding. Hereinafter, this effect will be described in detail.

  For example, if each cover of the telescopic cover is separately molded by blow molding, it is necessary to prepare a mold matched to each cover, and the cost of the mold increases according to the number of covers. In addition, in order to form each cover separately, the processing capacity of the blow molding machine needs to have the ability to compensate for the number of telescopic covers required multiplied by the number of covers used for telescopic covers. Such costs will increase. Furthermore, when the apparatus price of the vacuum forming machine and the blow molding machine are compared, the blow molding machine requires a parison extruder etc., so even with the same processing capacity, the price is higher than that of the vacuum forming machine, and the initial cost increases. There is a case.

  On the other hand, in the configuration according to the present embodiment, the molded article 100 including each cover of the telescopic cover 23 is formed by blow molding, and the molded article 100 is cut to form each cover of the telescopic cover 23 it can. That is, since a plurality of covers can be formed by one mold 200, the number of molds required when manufacturing one telescopic cover 23 can be reduced. Thus, the cost of the mold can be reduced.

  Furthermore, since the configuration according to the present embodiment can form each cover of the telescopic cover in a single blow molding, it is possible to reduce the required processing capacity of the blow molding machine. Thus, the cost of the blow molding machine can be reduced. Furthermore, by using blow molding, it is possible to form a cover which is thicker than vacuum forming and which is excellent in strength and rigidity. Therefore, the reduction in yield can be suppressed more than when vacuum forming is used. Therefore, with the configuration according to the present embodiment, an increase in the manufacturing cost of the cover by blow molding can be suppressed.

  Furthermore, with the configuration according to the present embodiment, by using blow molding, it is possible to form a cover that is thicker than vacuum forming and is excellent in strength and rigidity. Therefore, it is possible to reduce the probability that defects such as breakage of the cover will occur after shipping the bed apparatus attached with the cover. Therefore, maintenance costs such as replacement of the cover can be reduced.

  Furthermore, with the configuration according to the present embodiment, each cover of the telescopic cover 23 can be formed by one mold 200. For this reason, when changing the shape of each cover of the telescopic cover 23, the shape of each cover can be changed by changing the shape of the mold 200. Therefore, the number of molds to be changed can be reduced compared to molding each cover individually, and the cost of the molds associated with the change can be reduced.

  Also, by using blow molding, a relatively tall cover can be formed as compared to the case of using vacuum molding. For this reason, the number of covers of the telescopic cover can be reduced as compared with the case of using vacuum forming. As a result, the diameter of the telescopic cover can be reduced, so that the increase in the area of the telescopic cover in the horizontal direction can be suppressed.

2. Second Embodiment Next, a second embodiment will be described. In the second embodiment, a case will be described in which a shape serving as a guide for a cutter or the like is provided when cutting at the cutting position in the molded article 100.

2.1 Cross-Sectional Shape of Molded Product The cross-sectional shape of the molded product 100 will be described with reference to FIG. FIG. 12 shows an enlarged view in a region AR in the vicinity of the cross section of the second cutout portion 103 in the molded article 100 of the present embodiment, as in FIG. 9 of the first embodiment.

  As shown in FIG. 12, the molded article 100 in the present embodiment has a concave guide 112 a corresponding to the second cutting position 112 and a concave guide 113 a corresponding to the third cutting position 113. In the example shown in FIG. 12, the guides 112a and 113a are shown, but the molded article 100 has the guide 111a corresponding to the first cutting position 111, the guide 114a corresponding to the fourth cutting position 114, and the fifth cutting position 115 And a guide 116a corresponding to the sixth cutting position 116, respectively.

  The guide 112 a facilitates visual recognition of the second cutting position 112, and the side surface of the concave portion prevents positional deviation of the second cutting position 112 by applying the blade into the recess when cutting with a blade or the like. The same applies to the guide 113a. Each guide may be provided so as to surround the outer periphery of the molded article 100, or may be provided on a part of the outer periphery. Furthermore, the shape to be a guide is not limited to the concave shape. For example, a convex shape may be used, and a convex shape may be provided above and below the cutting position of the molded article 100 to cut between the two convex shapes.

2.2 Configuration according to the present embodiment With the configuration according to the present embodiment, the same effects as in the first embodiment can be obtained.

  Furthermore, with the configuration according to the present embodiment, when cutting the molded article 100, for example, it is possible to cut along the guide without preparing a dedicated jig or device for accurately adjusting the cutting position. Therefore, the cutting operation of the molded article 100 can be facilitated. Furthermore, the cost for equipment can be reduced because a dedicated jig or device is not required.

3. Modified example etc
The embodiment is not limited to the above-described embodiment, and various modifications are possible.

  For example, although the case where the molded article 100 including the first cover 33, the second cover 34, and the third cover 35 is molded has been described in the above embodiment, the first cover 33, the second cover 34, and the third cover A molded article including a plurality of covers 35 may be molded. More specifically, for example, the molded product may have a shape in which two molded products 100 shown in FIG. 7 are connected. Since one end (first cut-out portion) and the other end (fourth cut-out portion) of the molded article 100 shown in FIG. 7 are not used as a cover, a structure in which a plurality of molded articles 100 shown in FIG. Even the shape of the cover after cutting is not affected.

  Further, in the above embodiment, although the case where the molded article 100 including the first cover 33, the second cover 34, and the third cover 35 is molded has been described, the first cover 33, the second cover 34, and the third You may shape | mold the molded article which contains two or more of any of the cover 35. FIG. More specifically, for example, a first molded article including three first covers 33, a second molded article including three second covers 34, and a third molded article including three third covers 35 are formed. By cutting these, three telescopic covers 23 may be manufactured.

  Moreover, although the said embodiment demonstrated the case where blow molding of the molded article provided with each cover of a telescopic cover was carried out, a cover is not limited to a telescopic cover. Furthermore, a molded article may be formed that includes a plurality of products having a cylindrical shape with both ends open.

  The present invention is not limited to the above embodiment, and can be variously modified in the implementation stage without departing from the scope of the invention. In addition, the embodiments may be implemented in combination as appropriate, in which case the combined effect is obtained. Furthermore, various inventions are included in the above-described embodiment, and various inventions can be extracted by a combination selected from a plurality of disclosed configuration requirements. For example, even if some configuration requirements are deleted from all the configuration requirements shown in the embodiment, the problem can be solved, and if an effect is obtained, a configuration from which this configuration requirement is removed can be extracted as the invention.

  DESCRIPTION OF SYMBOLS 1 ... stretcher, 2 ... inside floor, 3 ... truck, 4 ... post, 5 ... mattress, 6 ... main frame, 7 ... back bottom, 8 ... knee bottom, 9 ... foot bottom, 10 ... transfer board, 11 ... transportation Handle 12 12 back lift lever 13 knee lift handle 14 corner bumper 15 truck cover 16 caster 17 caster operation pedal 18 lift pedal 19 toe pedal 20 toe pedal , 21 ... lowering pedal, 22 ... hydraulic cylinder, 23 ... telescopic cover, 31 ... cylinder, 32 ... piston rod, 33 to 35 ... cover, 36 ... top cover, 37 ... rod receptacle, 38, 39 ... frame, 40 ... mounting bracket , 41, 42: threaded hole, 43: mounting portion, 50, 52, 54: inner flange, 51, 53: outer flange, 100: molded article 101, 103, 105, 107 ... cutting part, 102, 104, 106 ... cover part, 111 to 116 ... cutting position, 111a to 116a ... guide, 200 ... mold, 210, 220 ... divided mold, 211, 221 ... Cavity 212, 222 ... blow blow-in port, 213, 223 ... bite-out portion.

Claims (8)

Blow molding a molded article having a first cover part and a second cover part used for the cover, and a first cutout part contacting the first cover part and the second cover part;
And c. Cutting the molded product to separate the first cover portion, the first cutout portion, and the second cover portion. The method according to claim 1, further comprising the step of combining the first cover portion and the second cover portion which are separated. The method further includes the step of separating the first cover portion from the second cutting portion in contact with the first cover portion,
The outer diameter of the first opening of the first cover formed by separating the first cover and the second cutout is formed by separating the second cover and the first cutout. Larger than the outer diameter of the second opening of the second cover portion,
The outer diameter of the second opening is larger than the inner diameter of the third opening of the first cover formed by separating the first cover and the first cutout. Cover manufacturing method. The method for manufacturing a cover according to any one of claims 1 to 3, wherein the cover is used in a bed apparatus including a pedestal, an elevating device, and a bed unit. The first cover,
2nd cover part,
A first cutout contacting the first cover and the second cover;
A second cutout contacting the first cover and separated from the second cover;
And a third cutout contacting with the second cover and separated from the first cover,
The outer diameter of a first cutting position for separating the first cover portion and the second cutting portion is larger than the outer diameter of a second cutting position for separating the second cover portion and the first cutting portion,
The outer diameter of the second cutting position is larger than the outer diameter of a third cutting position for separating the first cover portion and the first cutting portion,
A molded article, wherein the outer diameter of the third cutting position is larger than the outer diameter of a fourth cutting position for separating the second cover portion and the third cutting portion. The first cover part separated from the first and second cutout parts and the second cover part separated from the second and third cutout parts are combined and used as a cover The molded article according to claim 5. The molded article according to claim 5, wherein the first cover portion and the second cover portion have parting lines. A first cover part, a second cover part, a first cutting part in contact with the first cover part and the second cover part, a second cutting part in contact with the first cover part and separated from the second cover part, And a cavity having a shape corresponding to a third cutout in contact with the second cover and separated from the first cover,
In the cavity, an inner diameter of a first position at which the first cover portion contacts the second cutout portion is larger than an inner diameter of a second position at which the second cover portion contacts the first cutout portion; The inner diameter at the two positions is larger than the inner diameter at the third position where the first cover portion and the first cutout contact each other, and the inner diameter at the third position is the second cover and the third cutout A mold for molding that is larger than the inner diameter of the fourth position at which it contacts.