CN213030629U

CN213030629U - Portable infrared blood vessel locator

Info

Publication number: CN213030629U
Application number: CN202021348025.8U
Authority: CN
Inventors: 黄正辉; 刘高伦; 赵文芳
Original assignee: First Peoples Hospital of Longquanyi District Chengdu
Current assignee: First Peoples Hospital of Longquanyi District Chengdu
Priority date: 2020-07-10
Filing date: 2020-07-10
Publication date: 2021-04-23
Anticipated expiration: 2030-07-10

Abstract

The utility model relates to a portable infrared blood vessel locator, which comprises an arm support, a guide mechanism, a slide bar, a support mechanism, a bottom plate, a clamping mechanism, an infrared blood vessel projector and an extension spring, wherein the arm support is of a groove-shaped structure with openings at two ends, and the side walls at two sides are arc-shaped; the guide mechanism is fixed at two ends of the outer surface of the bottom groove wall of the arm support along the width direction of the arm support, and a slideway is arranged in the length direction of the guide mechanism; the sliding rods are symmetrically arranged at two ends of the guide mechanism, are perpendicular to the guide mechanism, and are arranged in the slide way in a sliding manner at the ends, so that the sliding rods can slide along the slide way; the extension springs are symmetrically and fixedly connected to the end of the sliding rod; the supporting mechanism is arranged in an area enclosed by the guide mechanism and the sliding rod, one end of the supporting mechanism is fixed on the outer surface of the bottom groove wall of the arm support, and the other end of the supporting mechanism is fixed on the lower surface of the bottom plate; the clamping mechanism is arranged on the upper surface of the bottom plate, and the infrared blood vessel projector is clamped in the clamping mechanism.

Description

Portable infrared blood vessel locator

Technical Field

The utility model relates to the field of medical equipment, concretely relates to portable infrared blood vessel locator.

Background

In the process of clinical vessel puncture, part of patients have thick epidermis, blood vessels are thin and difficult to find, part of trauma patients have excessive blood loss, are unconscious and are not full of blood vessels, so that medical staff cannot find the blood vessels during intravenous injection, and infant patients have difficulty in finding the blood vessels due to physiological reasons and character characteristics of the infant patients, so that the time of the medical staff on a single patient is greatly increased, and the risks of body pain and mental stress of the patients are increased.

To solve this problem, it is critical how the blood vessels can be found. According to research, the near infrared light source can distinguish the red blood cells of subcutaneous veins or arteries from surrounding tissues according to specific wavelengths, the near infrared light penetrates through tissues of a human body, and the specific absorption spectrum characteristic of deoxyhemoglobin is utilized, so that the hemoglobin absorption peak value in venous blood is highest. By utilizing the characteristic of infrared light, the infrared blood vessel projection equipment capable of projecting blood vessels under the skin onto the skin after irradiating the skin is manufactured, the production of the equipment effectively lightens the labor intensity of medical staff on patients difficult to find blood vessels, and increases the accuracy of blood vessel finding.

Present infrared blood vessel projection equipment has handheld and non-handheld, and the precision of handheld is slightly low than the precision of non-handheld, only can play the effect of instructing the blood vessel, can not be to the precision that non-handheld, but handheld compare in the infrared blood vessel projection equipment of non-handheld, small and exquisite light, conveniently carries.

For general infusion and injection, the position of a blood vessel can be indicated by using the handheld infrared blood vessel projection device, and the positioning function is realized, so that the handheld infrared blood vessel projector is completely suitable for infusion and injection. However, although the handheld infrared blood vessel projector is small and exquisite and convenient to carry, it is still inconvenient for medical staff to perform an injection, for example, during the injection, the medical staff needs both hands to perform an operation, and at this time, the medical staff has no ability to use the handheld infrared blood vessel projector and perform the injection operation. For a conscious patient, medical staff can still use the infrared blood vessel projection equipment by themselves to assist the medical staff to insert a needle, but for a unconscious patient or a patient who is not awake after operation, the method is not feasible, and for the tense manpower resources in hospitals, the method is unrealistic by adding an auxiliary medical staff. For some patients needing frequent transfusion, in order to reduce the pain of puncturing veins each time, a trocar can be kept in a vein, even considering that the patients need long-term transfusion, a transfusion catheter can be kept in a vena cava, and in addition, the patients needing hemodialysis treatment need jugular vein or femoral vein puncturing catheterization, but veins at the positions are deep and difficult to find by naked eyes, so that the working difficulty of medical staff is increased.

Therefore, if the problem that the medical staff cannot perform the needle inserting operation when using the infrared blood vessel projection equipment can be solved, the working difficulty of the medical staff can be effectively reduced.

So the utility model discloses just design to these problems, in order to solve the problem that medical personnel can't carry out the operation of pricking when using infrared blood vessel projection equipment at present.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that the unable fine solution of prior art can't carry out the problem of the operation of pricking when using infrared blood vessel projection equipment at present medical personnel.

The utility model discloses a following technical scheme realizes:

the portable infrared blood vessel locator comprises an arm support, a guide mechanism, a sliding rod, a supporting mechanism, a bottom plate, a clamping mechanism, an infrared blood vessel projector and an extension spring, wherein the arm support is of a groove-shaped structure with openings at two ends, and the side walls at two sides of the arm support are arc-shaped; the guide mechanism is fixed at two ends of the outer surface of the bottom groove wall of the arm support along the width direction of the arm support, and a slideway is arranged in the length direction of the guide mechanism; the sliding rods are symmetrically arranged at two ends of the guide mechanism, are perpendicular to the guide mechanism, and are arranged in the slide way in a sliding manner at the ends, so that the sliding rods can slide along the slide way; the extension springs are symmetrically and fixedly connected to the end of the sliding rod; the supporting mechanism is arranged in an area enclosed by the guide mechanism and the sliding rod, one end of the supporting mechanism is fixed on the outer surface of the bottom groove wall of the arm support, and the other end of the supporting mechanism is fixed on the lower surface of the bottom plate; the clamping mechanism is arranged on the upper surface of the bottom plate, and the infrared blood vessel projector is clamped in the clamping mechanism. For general infusion and injection, the position of a blood vessel can be indicated by using the handheld infrared blood vessel projection device, and the positioning function is realized, so that the handheld infrared blood vessel projector is completely suitable for infusion and injection. However, although the handheld infrared blood vessel projector is small and exquisite and convenient to carry, it is still inconvenient for medical staff to perform an injection, for example, during the injection, the medical staff needs both hands to perform an operation, and at this time, the medical staff has no ability to use the handheld infrared blood vessel projector and perform the injection operation. For a conscious patient, medical staff can still use the infrared blood vessel projection equipment by themselves to assist the medical staff to insert a needle, but for a unconscious patient or a patient who is not awake after operation, the method is not feasible, and for the tense manpower resources in hospitals, the method is unrealistic by adding an auxiliary medical staff. So the utility model discloses just design to these problems, in order to solve the problem that medical personnel can't carry out the operation of pricking when using infrared blood vessel projection equipment at present. The utility model discloses a set up the arm support, can block the arm support on the forearm that is close to the wrist, make the whole equipment that sets up on the arm support block and on medical personnel's arm, liberated medical personnel's both hands, make medical personnel can use infrared blood vessel projection equipment to carry out the projection of blood vessel when pricking the needle, carry out preliminary location to the blood vessel, reach the effect of instructing the blood vessel position; the slide rod can slide along the slide way on the guide mechanism by arranging the guide mechanism and the slide rod; the symmetrically arranged slide bars can be connected through the extension spring by arranging the extension spring at the end of the slide bar, and the slide bar can restore the relative state of the slide bar through the elasticity of the extension spring after the force which makes the slide bar relatively far away is removed; meanwhile, by arranging the supporting mechanism and the bottom plate, the bottom plate can be far away from the bottom plate after the supporting mechanism is stretched, and the bottom plate is in a certain inclination, so that irradiation light projected by infrared blood vessels arranged on the bottom plate and projection light can be conveniently radiated to the skin on the back of the hand; the limiting groove is formed in the bottom plate, the limiting strip is arranged on the sliding rod, so that the limiting strip can be clamped into the limiting groove under the condition that the hinged blocks are closed, namely the bottom plate is not far away from the arm support and is embedded in an area defined by the guide mechanism and the sliding rod, the purpose of fixing the bottom plate is achieved, and meanwhile, the infrared blood vessel projector arranged on the bottom plate is fixed; the pull block is pulled to drive the extension spring to extend, so that the limit fixing state of the bottom plate can be released; through setting up fixture, can be with the infrared blood vessel projecting apparatus centre gripping between the supporting rod that the symmetry set up, the supporting rod is the body of rod that has certain elastic restoring force for the infrared blood vessel projecting apparatus centre gripping can make the supporting rod outwards crooked when between the supporting rod, and the supporting rod produces inside restoring force simultaneously, thereby live infrared blood vessel projecting apparatus centre gripping.

According to a preferred embodiment, the guide means is of a rectangular parallelepiped configuration, and the runners are channel-shaped, are provided at the center of the opposing faces of the symmetrical guide means, and are arranged along the length thereof. The sliding rod comprises a rod body, rollers, a limiting strip, a pulling block connecting rod and a pulling block, wherein the rod body is of a cuboid structure, symmetrically arranged at two ends of the guide mechanism and vertically arranged with the guide mechanism; the rollers are symmetrically arranged at the central positions of the two ends of the rod body and extend into the slide way; the pull block connecting rod is fixed at the center of the outer side wall of the rod body, and the pull block is fixed on the pull block connecting rod; the limiting strip is of an arc-shaped column structure and is fixed at the central position of the rod body relative to the other side wall of the side wall fixed with the pull block connecting rod along the length direction of the rod body. The slide bar can slide in the slide way by arranging the guide mechanism.

According to a preferred embodiment, the supporting mechanism comprises a hinge block and a hinge strip, the hinge block is of a cuboid structure, a groove with the depth being half of the width of the hinge strip is formed in the center of the hinge block along the length direction, and the hinge block is oppositely arranged on the outer surface of the wall of the bottom groove of the arm support and the lower surface of the bottom plate; the hinge bars are hinged on the side wall of the groove of the hinge block on the arm support, the other hinge bar is hinged on the side wall of the groove of the hinge block on the bottom plate, one ends of the two hinge bars are hinged, under the condition that the hinge blocks are oppositely combined, the arm support and the bottom plate are in a parallel state, and the hinge bars are embedded in the grooves of the oppositely combined hinge blocks. Through setting up supporting mechanism and making the bottom plate can reach the bottom plate through stretching out or the condensation of supporting mechanism and fix a certain position, perhaps reach the angle of a certain slope to make the infrared blood vessel projector of centre gripping on the bottom plate can reach required height or required angle, make light can reach on the skin of hand quilt.

According to a preferred embodiment, the clamping mechanism includes a clamping table fixed to the upper surface of the base plate, and clamping rods of a gamma type structure fixed to the clamping table. The clamping mechanisms are arranged symmetrically along the long edge direction of the bottom plate. Through setting up a plurality of fixture of symmetry for fixture has sufficient clamping-force and presss from both sides infrared blood vessel projecting apparatus centre gripping on the bottom plate.

According to a preferred embodiment, the bottom plate comprises a plate body, the shape of the plate body is the same as that of an area surrounded by the guide mechanism and the slide rod, and a limit groove matched with the limit strip is arranged on one side wall of the rod body corresponding to the limit strip along the long side direction of the bottom plate, so that the limit strip can be clamped into the limit groove under the condition that the hinge blocks are closed.

Compared with the prior art, the utility model, can realize one or several following beneficial effect:

the utility model discloses a set up the arm support, can block the arm support on the forearm that is close to the wrist, make the whole equipment that sets up on the arm support block and on medical personnel's arm, liberated medical personnel's both hands, make medical personnel can use infrared blood vessel projection equipment to carry out the projection of blood vessel when pricking the needle, carry out preliminary location to the blood vessel, reach the effect of instructing the blood vessel position; meanwhile, by arranging the supporting mechanism and the bottom plate, the bottom plate can be far away from the bottom plate after the supporting mechanism is stretched, and the bottom plate is in a certain inclination, so that irradiation light projected by infrared blood vessels arranged on the bottom plate and projection light can be conveniently radiated to the skin on the back of the hand; the limiting groove is formed in the bottom plate, the limiting strip is arranged on the sliding rod, so that the limiting strip can be clamped into the limiting groove under the condition that the hinged blocks are closed, namely the bottom plate is not far away from the arm support and is embedded in an area defined by the guide mechanism and the sliding rod, the purpose of fixing the bottom plate is achieved, and meanwhile, the infrared blood vessel projector arranged on the bottom plate is fixed; through setting up fixture, can be with the infrared blood vessel projecting apparatus centre gripping between the supporting rod that the symmetry set up, the supporting rod is the body of rod that has certain elastic restoring force for the infrared blood vessel projecting apparatus centre gripping can make the supporting rod outwards crooked when between the supporting rod, and the supporting rod produces inside restoring force simultaneously, thereby live infrared blood vessel projecting apparatus centre gripping.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:

fig. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic structural view of the arm support and the guiding mechanism of the present invention;

FIG. 3 is a schematic structural view of the slide bar of the present invention;

fig. 4 is a schematic structural diagram of the supporting mechanism, the bottom plate, the clamping mechanism and the infrared blood vessel projector according to the present invention;

fig. 5 is a schematic structural view of the arm support of the present invention;

FIG. 6 is a schematic structural view of the arm support and the slide bar of the present invention;

FIG. 7 is a schematic structural view of the arm support, the guide mechanism and the slide rod of the present invention;

fig. 8 is a schematic structural view of the arm support and the support mechanism of the present invention.

Reference numbers and corresponding part names in the drawings:

the device comprises an arm support 1, an arm support 2, a guide mechanism 21, a slideway 3, a slide rod 31, a rod body 32, a roller 33, a limiting strip 34, a pull block connecting rod 35, a pull block 4, a support mechanism 41, a hinge block 42, a base plate 5, a plate body 51, a limiting groove 52, a clamping mechanism 6, a clamping table 61, a clamping rod 62, an infrared blood vessel projector 7 and an extension spring 8.

Detailed Description

To make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the following examples and drawings, and the exemplary embodiments and descriptions thereof of the present invention are only used for explaining the present invention, and are not intended as limitations of the present invention.

As shown in fig. 1-8, the utility model relates to a portable infrared blood vessel locator, which comprises an arm support 1, a guide mechanism 2, a slide bar 3, a support mechanism 4, a bottom plate 5, a clamping mechanism 6, an infrared blood vessel projector 7 and an extension spring 8, wherein the arm support 1 is a groove-shaped structure with openings at two ends, and the side walls at two sides are arc-shaped; the guide mechanism 2 is fixed at two ends of the outer surface of the bottom groove wall of the arm support 1 along the width direction of the arm support 1, and a slide way 21 is arranged in the length direction of the guide mechanism; the sliding rods 3 are symmetrically arranged at two ends of the guide mechanism 2, are perpendicular to the guide mechanism 2, and are arranged in the slide rail 21 in a sliding manner at the ends thereof, so that the sliding rods 3 can slide along the slide rail 21; the extension springs 8 are symmetrically and fixedly connected to the end of the sliding rod 3; the supporting mechanism 4 is arranged in an area enclosed by the guide mechanism 2 and the slide bar 3, one end of the supporting mechanism is fixed on the outer surface of the bottom groove wall of the arm support 1, and the other end of the supporting mechanism is fixed on the lower surface of the bottom plate 5; the clamping mechanism 6 is arranged on the upper surface of the bottom plate 5, and the infrared blood vessel projector 7 is clamped in the clamping mechanism 6. The utility model discloses a set up the arm support, can block the arm support on the forearm that is close to the wrist, make the whole equipment that sets up on the arm support block and on medical personnel's arm, liberated medical personnel's both hands, make medical personnel can use infrared blood vessel projection equipment to carry out the projection of blood vessel when pricking the needle, carry out preliminary location to the blood vessel, reach the effect of instructing the blood vessel position; the slide rod can slide along the slide way on the guide mechanism by arranging the guide mechanism and the slide rod; the symmetrically arranged slide bars can be connected through the extension spring by arranging the extension spring at the end of the slide bar, and the slide bar can restore the relative state of the slide bar through the elasticity of the extension spring after the force which makes the slide bar relatively far away is removed; meanwhile, by arranging the supporting mechanism and the bottom plate, the bottom plate can be far away from the bottom plate after the supporting mechanism is stretched, and the bottom plate is in a certain inclination, so that irradiation light projected by infrared blood vessels arranged on the bottom plate and projection light can be conveniently radiated to the skin on the back of the hand; the limiting groove is formed in the bottom plate, the limiting strip is arranged on the sliding rod, so that the limiting strip can be clamped into the limiting groove under the condition that the hinged blocks are closed, namely the bottom plate is not far away from the arm support and is embedded in an area defined by the guide mechanism and the sliding rod, the purpose of fixing the bottom plate is achieved, and meanwhile, the infrared blood vessel projector arranged on the bottom plate is fixed; the pull block is pulled to drive the extension spring to extend, so that the limit fixing state of the bottom plate can be released; through setting up fixture, can be with the infrared blood vessel projecting apparatus centre gripping between the supporting rod that the symmetry set up, the supporting rod is the body of rod that has certain elastic restoring force for the infrared blood vessel projecting apparatus centre gripping can make the supporting rod outwards crooked when between the supporting rod, and the supporting rod produces inside restoring force simultaneously, thereby live infrared blood vessel projecting apparatus centre gripping.

Preferably, the guide mechanism 2 is a rectangular parallelepiped structure, and the slide rail 21 is groove-shaped, is provided at the center of the opposite surfaces of the symmetrical guide mechanism 2, and is provided along the length direction thereof.

Preferably, the sliding rod 3 comprises a rod body 31, a roller 32, a limiting strip 33, a pulling block connecting rod 34 and a pulling block 35, wherein the rod body 31 is of a cuboid structure, symmetrically arranged at two ends of the guide mechanism 2 and vertically arranged with the guide mechanism 2; the rollers 32 are symmetrically arranged at the central positions of the two ends of the rod body 31, and the rollers 32 extend into the slide rail 21; the pull block connecting rod 34 is fixed at the center of the outer side wall of the rod body 31, and the pull block 35 is fixed on the pull block connecting rod 34; the position-limiting bar 33 is an arc-shaped column structure, and is fixed at the center of the rod body 31 relative to the other side wall of the side wall to which the pull block connecting rod 34 is fixed along the length direction of the rod body 31.

Preferably, the supporting mechanism 4 comprises a hinge block 41 and a hinge strip 42, the hinge block 41 is a cuboid structure, a groove with a depth being half of the width of the hinge strip 42 is formed in the center of the hinge block 41 along the length direction, and the hinge block 41 is oppositely arranged on the outer surface of the bottom groove wall of the arm support 1 and the lower surface of the bottom plate 5; the two hinge strips 42 are hinged on the side wall of the groove of the hinge block on the arm support 1, the other hinge strip is hinged on the side wall of the groove of the hinge block on the bottom plate 5, one ends of the two hinge strips 42 are hinged, under the condition that the hinge blocks 41 are oppositely arranged, the arm support 1 and the bottom plate 5 are in a parallel state, and the hinge strips 42 are embedded in the grooves of the oppositely arranged hinge blocks 41.

Preferably, the clamping mechanism 6 includes a clamping table 61 and a clamping bar 62, the clamping table 61 is fixed on the upper surface of the base plate 5, and the clamping bar 62 is of a gamma type structure and is fixed on the clamping table 61.

Preferably, the clamping mechanisms 6 are provided in a plurality, and are symmetrically arranged along the long side direction of the bottom plate 5.

Preferably, the bottom plate 5 includes a plate body 51, which has the same shape as the area enclosed by the guide mechanism 2 and the slide rod 3, and a limit groove 52 corresponding to the limit bar 33 is formed on a side wall of the rod body 31 provided with the limit bar 33 along the long side direction of the bottom plate 5, so that the limit bar 33 can be locked into the limit groove 52 when the hinge blocks 41 are coupled.

The above-mentioned embodiments, further detailed description of the objects, technical solutions and advantages of the present invention, it should be understood that the above description is only the embodiments of the present invention, and is not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. The portable infrared blood vessel locator is characterized by comprising an arm support (1), a guide mechanism (2), a sliding rod (3), a supporting mechanism (4), a bottom plate (5), a clamping mechanism (6), an infrared blood vessel projector (7) and an extension spring (8), wherein the arm support (1) is of a groove-shaped structure with openings at two ends, and the side walls of two sides of the arm support are arc-shaped; the guide mechanisms (2) are fixed at two ends of the outer surface of the bottom groove wall of the arm support (1) along the width direction of the arm support (1), and a slide way (21) is arranged in the length direction of the guide mechanisms; the sliding rods (3) are symmetrically arranged at two ends of the guide mechanism (2) and are perpendicular to the guide mechanism (2), and the ends of the sliding rods (3) are slidably arranged in the slide ways (21), so that the sliding rods (3) can slide along the slide ways (21); the extension springs (8) are symmetrically and fixedly connected to the end heads of the sliding rods (3); the supporting mechanism (4) is arranged in an area surrounded by the guide mechanism (2) and the sliding rod (3), one end of the supporting mechanism is fixed on the outer surface of the bottom groove wall of the arm support (1), and the other end of the supporting mechanism is fixed on the lower surface of the bottom plate (5); the clamping mechanism (6) is arranged on the upper surface of the bottom plate (5), and the infrared blood vessel projector (7) is clamped in the clamping mechanism (6).

2. The portable infrared blood vessel locator as claimed in claim 1, wherein the guide mechanism (2) is a rectangular parallelepiped structure, and the slide way (21) is groove-shaped, is provided at the center of the opposite faces of the symmetrical guide mechanism (2), and is provided along the length direction thereof.

3. The portable infrared blood vessel locator as claimed in claim 2, wherein the slide bar (3) comprises a bar body (31), a roller (32), a limit strip (33), a pull block connecting bar (34) and a pull block (35), the bar body (31) is a cuboid structure, symmetrically arranged at two ends of the guide mechanism (2) and vertically arranged with the guide mechanism (2); the rollers (32) are symmetrically arranged at the central positions of two ends of the rod body (31), and the rollers (32) extend into the slide way (21); the pull block connecting rod (34) is fixed at the central position of the outer side wall of the rod body (31), and the pull block (35) is fixed on the pull block connecting rod (34); the limiting strip (33) is of an arc-shaped column structure and is fixed at the center of the rod body (31) relative to the other side wall of the side wall on which the pull block connecting rod (34) is fixed along the length direction of the rod body (31).

4. The portable infrared blood vessel positioner as claimed in claim 3, wherein the supporting mechanism (4) comprises a hinge block (41) and a hinge strip (42), the hinge block (41) is a cuboid structure, the central position of the hinge block (41) is provided with a groove with a depth half of the width of the hinge strip (42) along the length direction, and the hinge block (41) is oppositely arranged on the outer surface of the bottom groove wall of the arm support (1) and the lower surface of the bottom plate (5); the two hinge strips (42) are hinged to the side wall of the groove of the hinge block on the arm support (1), the other hinge strip is hinged to the side wall of the groove of the hinge block on the bottom plate (5), one ends of the two hinge strips (42) are hinged, under the condition that the hinge blocks (41) are oppositely arranged, the arm support (1) and the bottom plate (5) are in a parallel state, and the hinge strips (42) are embedded in the grooves of the oppositely arranged hinge blocks (41).

5. The portable infrared blood vessel locator as recited in claim 4, wherein the clamping mechanism (6) comprises a clamping table (61) and a clamping rod (62), the clamping table (61) is fixed on the upper surface of the base plate (5), and the clamping rod (62) is of a + -type structure and fixed on the clamping table (61).

6. The portable infrared blood vessel locator as claimed in claim 5, characterized in that the clamping mechanisms (6) are arranged symmetrically along the long side direction of the bottom plate (5).

7. The portable infrared blood vessel locator as claimed in claim 6, wherein the bottom plate (5) comprises a plate body (51) which has the same shape as the area enclosed by the guide mechanism (2) and the slide bar (3), and a limit groove (52) matched with the limit strip (33) is arranged on the side wall of one side of the rod body (31) corresponding to the limit strip (33) along the long side direction of the bottom plate (5), so that the limit strip (33) can be clamped into the limit groove (52) under the condition that the hinge blocks (41) are oppositely arranged.