JP2019049124A - handrail - Google Patents

Abstract

An object of the present invention is to provide a handrail excellent in safety that can surely prevent a lock mechanism from being unlocked accidentally while being a handrail that can be expanded and contracted. An outer handrail 11 and an inner handrail 12 having a nesting structure, a switching mechanism 13 fixed to one handrail 11, and a lock mechanism 14 accommodated in the other handrail 12 are provided. The switching mechanism 13 includes a transmission structure that is rotated by the operation tool 40, and a screw structure that converts the rotational operation of the transmission structure into a reciprocating operation. The switching mechanism 13 and the lock mechanism 14 are connected by a switching shaft 16 that transmits a reciprocating motion. The lock mechanism 14 includes a movable cam block 53 that receives a reciprocating motion of the switching shaft 16 and switches between a lock posture and a lock release posture. The movable cam block 53 switched to the locked posture is in close contact with the inner surface of the handrail 12 and locks and fixes both handrails 11 and 12 so that they cannot expand and contract. [Selection] Figure 1

Description

  The present invention relates to, for example, a handrail that is disposed between adjacent columns and that can be adjusted to expand and contract depending on the difference in the adjacent spacing of the columns.

  The applicant manufactures and sells care products for the purpose of fall prevention, assistance in movement, assistance in transfer, and rehabilitation. For example, according to the indoor situation and the exercise capacity of the care recipient, etc., the purpose is to construct a brace-fixed type post installed between the floor and the ceiling wall and a handrail connecting the adjacent posts. I am able to help. Since this kind of care product is widely applied from care facilities to general homes, it is necessary to install a support in relation to the position of a bed installed in a living room, for example, avoiding a wall outlet provided on the wall. Adjacent spacing often varies from construction site to construction site. Therefore, conventionally, a longer handrail is prepared, and when the support position of the support is determined, both ends of the handrail cut to a necessary length are fixed and supported by the bracket fixed to the support.

  If expansion and contraction adjustment can be performed according to the difference in the distance between adjacent columns, it is not necessary to cut the handrail to a required length, and construction work is simplified by preparing a plurality of handrails with different adjustment ranges. Can be However, in the case of assistance handrails, it is necessary to demonstrate the same feeling of use as a rod-like handrail not equipped with an adjustment function, and obstacles such as a screw operation head and an adjustment ring project in the middle part Technical hurdles are high because it is considered that structural requirements are not made.

  The present applicant has previously proposed an auxiliary handrail that allows the height of the handrail body to be finely changed and adjusted according to the difference in the physical constitution of the user and the difference in the level difference of the rising heel (Patent Document 1). . There, the auxiliary handrail is constituted by a bracket fixed to the step portion of the rising ridge and a handrail main body erected and supported by the bracket. The handrail main body includes a first leg supported by the bracket, a second leg supported on the lower floor of the step, and two types of handrails supported by the both legs. The bracket is equipped with a clamp device that can fix the first pedestal in any vertical position, and the second pedestal has a nested adjustment leg, a fixed leg, and a lock that fixes the adjustment leg in any adjustment position. Have. According to such an auxiliary handrail, the height of the handrail main body can be finely changed and adjusted by operating the clamp device and the locking tool.

  With respect to the handrail of the present invention, it is disclosed in Patent Document 2 that a telescopic adjustable clothesline is constituted by a nested outer pole and a pair of left and right inner poles. There, the cross-sectional shape of the outer pole and the pair of left and right inner poles is formed in a substantially square shape, and the expandable lock body is provided at the inner end of the inner pole inserted into the outer pole. The telescopic lock body includes a shaft fixed to the end of the inner pole and a pair of crimped bodies which are expanded and contracted by the shaft, and by rotating the inner pole and the shaft in a predetermined direction, The crimped body can be extended and deformed to be in close contact with the inner surface of the outer pole, and the inner pole can be fixed to the outer pole at any adjustment position.

JP, 2005-89974, A (abstract, FIG. 1) JP, 2017-64313, A (paragraph number 0025, FIG. 7)

  According to the clothes dryer of Patent Document 2, by rotating the outer end of the inner pole, the inner pole can be fixed at any adjustment position with respect to the outer pole. No obstructions on the outside of each pole. Therefore, when the adjustment structure of Patent Document 2 is applied to a handrail, a handrail that can exhibit a feeling of use equivalent to that of a rod-like handrail not having an adjustment function can be configured. However, in the case of the clothes dryer of Patent Document 2, it is necessary to make the cross-sectional shape of the outer pole and the pair of left and right inner poles into a square in order to prevent the pair of crimped bodies from rotating with the inner pole and the shaft. It is unsuitable for applying to handrails for nursing care. By the way, although the cross section of the handrail for care is basically circular, depending on the purpose of assistance, an oval or an oval shape with flat upper and lower surfaces is used.

  Further, in the clothes dryer of Patent Document 2, by rotating the inner pole 90 degrees with respect to the outer pole, the crimped body is extended and deformed to be in close contact with the inner surface of the outer pole, and the inner pole is arbitrarily adjusted. It can be fixed to the outside pole. However, there is a possibility that the expansion posture of the crimped body may be released and the expandable lock body may be unlocked only by rotating the inner pole in the reverse direction with respect to the outer pole. For example, the position of the care recipient who is walking while holding the inner pole may collapse, and the inner pole may be rotated in a direction in which the lock is released. In addition, when the handrail is used on a daily basis, there is also a possibility that the inner pole may be rotated little by little in the direction for unlocking. If the telescopic lock body has been unlocked, the inner pole and the outer pole can slide relative to each other, so that the weight of the care recipient in need of posture may act on one of the pillars, which is sufficient for safety. Can be a fatal flaw in care products that are required.

SUMMARY OF THE INVENTION An object of the present invention is to provide a handrail excellent in safety that can securely prevent the lock mechanism from being unlocked while being a telescopic adjustable handrail.
The object of the present invention is to eliminate excessive external force acting on the component parts of the switching mechanism, and to prevent premature failure or wear of the component parts, and hence durability and reliability in long-term use To provide a handrail that is excellent in expansion and contraction adjustment.

  In the handrail according to the present invention, the switching mechanism is fixed to the connecting end of the outer handrail 11 and the inner handrail 12 of the nested structure disposed between the adjacent columns 1 and 1 and the column 1 of either handrail 11 13 and a lock mechanism 14 housed inside the other handrail 12 and supported by a fixed frame 15 fixed to the switching mechanism 13. The outer handrail 11 and the inner handrail 12 are each non-rotatably connected to the support 1. The switching mechanism 13 includes a transmission structure rotated by the operation tool 40 from the outer surface of the handrail 11 and a screw structure converting a rotational movement of the transmission structure into a reciprocating movement. As shown in FIG. 1, the switching mechanism 13 and the locking mechanism 14 are connected by a switching shaft 16 that transmits the reciprocating motion converted by the screw structure to the locking mechanism 14. The lock mechanism 14 is provided with a movable cam block 53 which is operated to be displaced between a lock posture in which it is crimped to the inner surface of the other handrail 12 in response to the reciprocation of the switching shaft 16 and a lock release posture. In a state where the outer handrail 11 and the inner handrail 12 are extended and contracted to an arbitrary adjustment position, the movable cam block 53 is switched to the lock posture by rotating the switching mechanism 13 in a predetermined direction by the operation tool 40. It is characterized in that it adheres closely to the inner surface of the other handrail 12 and the handrails 11 and 12 can be locked so as not to be stretchable.

  As shown in FIG. 6, the switching mechanism 13 includes a base block 21 fixed inside the one handrail 11, a first bevel gear 22 rotatably supported by the base block 21, and a second bevel gear 23. It has a structure and a screw structure provided between the second bevel gear 23 and the switching shaft 16. By rotating the operation shaft 37 fixed to the first bevel gear 22 with the operation tool 40, the rotation center axis is converted to a direction along the center of the handrail 11 by the pair of bevel gears 22 and 23, and then the switching shaft 16 is screwed. Convert to the reciprocating operation of

  As shown in FIG. 9, the lock mechanism 14 is engaged with and supported by a fixed cam block 51 fixed to the fixed frame 15, an end block 52 fixed to the axial end of the switching shaft 16, and the end block 52 A movable cam block 53 that moves in the same direction as the movable member 52 is provided. The fixed cam block 51 and the movable cam block 53 are formed with a fixed cam body 56 and a movable cam body 69 which expand or contract the movable cam block 53 between the locking posture and the unlocking posture by contacting or separating from each other. By rotating the first bevel gear 22 with the operation tool 40 in a predetermined direction, the movable cam block 53 moves relative to the fixed cam block 51 and switches to the lock posture.

  The first bevel gear 22 is supported so as to reciprocate between a transmission attitude in which the base block 21 meshes with the second bevel gear 23 and a transmission cancellation attitude in which the second bevel gear 23 releases engagement with the second bevel gear 23. And the base block 21 is biased to move in a direction to hold the transmission posture by a limit spring 46. When the operation moment of the operation tool 40 acting on the first bevel gear 22 exceeds the appropriate value, as shown in FIG. 13, the first bevel gear 22 is switched to the transmission release posture against the biasing force of the limit spring 46 to idle. Do.

  On the opposing surfaces of the fixed cam block 51 and the movable cam blocks 53, 53, the first inclined cams 56A, 69A for converting the forward movement of the switching shaft 16 into the expanding operation of the movable cam block 53; The second inclined cam bodies 56B and 69B are formed to convert the moving operation into the expanding operation of the movable cam block 53 (see FIG. 8). Even if the rotational operation direction of the operation tool 40 is either rightward or leftward, the movable cam blocks 53 can be expanded by the fixed cam block 51 and switched to the lock posture.

  The base block 21 is composed of a pair of half blocks 21A and 21B divided by a plane passing through the rotation center axis of the second bevel gear 23 (see FIG. 5). The first bevel gear 22 and the second bevel gear 23 are rotatably supported by gear support concave portions 24 and 25 which are recessed in the joint surface of the pair of half blocks 21A and 21B, and the fixed frame 15 is paired with the half blocks 21A. It is engaged with and connected to the connecting recess 31 formed in a recess on the joint surface 21B.

  The lock mechanism 14 is provided with a pair of movable cam blocks 53 opposed to each other with the fixed cam block 51 interposed therebetween. As shown in FIG. 8, the end block 52 integrally includes an end boss 60 fastened and fixed to the axial end of the switching shaft 16 and a flange wall 61 formed so as to protrude on the circumferential surface on the fastening end side of the end boss 60. The pair of movable cam blocks 53, 53 are formed to extend over the friction lock wall 68 crimped to the inner surface of the other handrail 12, the movable cam body 69 formed on the inner surface of the wall 68, and the inner surface of the friction lock wall 68. Thus, the interlocking wall 70 for holding the flange wall 61 of the end block 52 in cooperation with the movable cam body 59 is integrally provided. The fixed cam block 51 is provided with a pair of fixed cam bodies 56 corresponding to the movable cam body 69. Movable cam blocks 53 and 53 are movably connected to the end block 52 via the movable cam body 59 sandwiching the flange wall 61 and the interlocking wall 70 and provided between the flange wall 61 and the interlocking wall 70 It is connected so as to be able to move in the radial direction via an engagement structure.

  The connection bosses 17 and 18 are provided at the connection end of the outer handrail 11 and the inner handrail 12 with the support 1, and the connection bosses 17 and 18 are fastened and fixed to the bracket 8 fixed to the support 1. And the inner handrail 12 is non-rotatably connected to and fixed to the support 1.

  The switching mechanism 13 is fixed to the connection end of the outer handrail 11 with the support 1, and the lock mechanism 14 is accommodated inside the inner handrail 12. The middle part of the fixed frame 15 is slidably guided and supported by a guide body 74 fixed to the connection end of the inner handrail 12 with the outer handrail 11. The guide body 74 doubles as a stopper that defines the extension limit of the outer handrail 11 and the inner handrail 12.

  The operating shaft 37 is fixed in a penetrating manner along the central axis of the first bevel gear 22. An operating head 37 b provided at an axial end of the operating shaft 37 faces the outer surface of the handrail 2 through an operating window 41 opened in the base block 21.

  In the handrail according to the present invention, the outer handrail 11 and the inner handrail 12 of the nested structure are connected non-rotatably to the column 1, the switching mechanism 13 fixed to either handrail 11, and the other handrail 12 It comprised with the lock mechanism 14 etc accommodated inside. Further, the switching mechanism 13 is constituted by a transmission structure and a screw structure for converting the rotational movement of the transmission structure into a reciprocating movement, and the converted reciprocating movement is transmitted to the lock mechanism 14 by the switching shaft 16. In use, the movable cam block 53 of the lock mechanism 14 is operated by rotating the switching mechanism 13 in a predetermined direction with the operation tool 40 in a state where the outer handrail 11 and the inner handrail 12 are extended and contracted to an arbitrary adjustment position. By switching to the lock position, the handrails 12 are brought into close contact with the inner surface of the other handrail 12 so that the handrails 11 and 12 can be locked and fixed so as not to be extensible.

  According to such a handrail, since the rotational movement of the transmission structure is converted to the reciprocating movement by the screw structure, the movable cam block 53 of the lock mechanism 14 is switched to the unlocking attitude unless the switching mechanism 13 is rotated by the operation tool 40. It is not possible. In addition, since the outer handrail 11 and the inner handrail 12 are non-rotatably connected to the support 1, the posture of the care recipient who is walking while holding the outer handrail 11 or the inner handrail 12 is broken. However, the movable cam block 53 does not switch to the unlocking posture. Therefore, it is a handrail that can be expanded and contracted, and even when a large external force acts on the outer handrail 11 and the inner handrail 12, it is surely prevented that the lock mechanism 14 is unlocked by mistake. Provide a handrail with excellent safety that can support the

  The switching mechanism 13 is configured by a transmission structure including the base block 21 and the pair of bevel gears 22 and 23 and a screw structure provided between the second bevel gear 23 and the switching shaft 16. In such a switching mechanism 13, only by operating the operation shaft 37 fixed to the first bevel gear 22 with the operation tool 40, the rotation center axis is converted to a direction along the center of the handrail 11 with the pair of bevel gears 22 and 23, and further The screw structure can be converted to the reciprocating motion of the switching shaft 16. That is, since the rotational movement of the operation tool 40 can be reliably converted to the reciprocating movement of the switching shaft 16 while minimizing the number of parts required for the movement conversion, the entire structure of the switching mechanism 13 is simplified and expansion and contraction adjustment is possible Can be provided at lower cost. In addition, since it is only necessary to rotate the switching mechanism 13 in a predetermined direction with the operation tool 40 in a state in which the outer handrail 11 and the inner handrail 12 are extended and contracted to an arbitrary adjustment position, the handrail installation work Everyone can do it easily.

  The lock mechanism 14 includes the fixed cam block 51, the end block 52, and the movable cam block 53, and the fixed cam body 56 and the movable cam body 69 are formed on the fixed cam block 51 and the movable cam block 53. I made it. According to the lock mechanism 14, by rotating the first bevel gear 22 with the operation tool 40, the movable cam block 53 can be moved relative to the fixed cam block 51 and switched to the lock posture. Further, the movable cam block 53 can not be returned to the unlocked position unless the first bevel gear 22 is rotated by the operation tool 40 in the reverse direction. Therefore, even when a large external force acts on the outer handrail 11 or the inner handrail 12, the movable cam block 53 is reliably prevented from switching to the unlocking posture, thereby further improving the safety of the handrail that can be expanded or contracted. can do.

  The first bevel gear 22 is supported by the base block 21 so as to be able to reciprocate, and the first bevel gear 22 is moved and biased by the limit spring 46 in the direction of holding the transmission posture. According to the switching mechanism 13, when the operation moment of the operation tool 40 acting on the first bevel gear 22 exceeds the appropriate value, the first bevel gear 22 is switched to the transmission release posture against the biasing force of the limit spring 46. Go around idle. Therefore, excessive external force acting on the component parts such as the gear teeth of the bevel gears 22 and 23 of the switching mechanism 13 and screw threads of the screw structure is eliminated, and the component parts may be damaged or worn prematurely. It can be eliminated. Accordingly, it is possible to provide a handrail that can be extended and contracted with excellent durability and reliability during long-term use.

  In the lock mechanism 14 in which the first inclined cam bodies 56A and 69A and the second inclined cam bodies 56B and 69B are formed on the fixed cam block 51 and the movable cam blocks 53 and 53, the rotational operation direction of the operation tool 40 is right and left. Regardless of the direction, the movable cam blocks 53 can be expanded by the fixed cam block 51 to switch from the unlocked position to the locked position. Therefore, the operator only has to turn the operation shaft 37 to either the left or the right with the operation tool 40, so that the lock fixing operation of the handrails 11 and 12 can be performed easily.

  The base block 21 is composed of a pair of half blocks 21A and 21B, and both bevel gears 22 and 23 are rotatably supported by gear support recesses 24 and 25 formed on the pair of half blocks 21A and 21B. Further, the fixed frame 15 is engaged with and coupled to the connecting recess 31 formed in the pair of half blocks 21A and 21B. According to the switching mechanism 13, after temporarily assembling the first and second bevel gears 22 and 23, the limit spring 46, the fixed frame 15 and the like into one half block 21B, the other half block 21A is firstly assembled. Since it is sufficient to join the half-split block 21B, a series of assembly operations can be performed easily and accurately while visually checking.

  For example, when the lock mechanism 14 is provided with a pair of movable cam blocks 53 opposed to each other with the fixed cam block 51 in between, the movable cam blocks 53 are made opposite to each other in close contact with the opposing wall of the inner surface of the inner handrail 12 The lock can be held in a firm state. Therefore, as compared with the case where the lock state is held by only one movable cam block 53, the lock mechanism 14 can be held in the lock posture more reliably to further improve the safety of the handrail. Further, the pair of movable cam blocks 53 and 53 and the end block 52 are movably connected in the same row, and are movably connected in the radial direction. According to the lock mechanism 14, after the fixed cam block 51 is fixed to the fixed frame 15 and the end block 52 is fixed to the switching shaft 16, the pair of movable cam blocks 53 is engaged with and coupled to the end block 52. Then, the lock mechanism 14 can be assembled. Therefore, it is possible to carry out a series of assembly operations in a reliable and easy manner while viewing.

  The outer bosses 11 and the inner handrail 12 are fixed to the support 1 by fastening and fixing the connection bosses 17 and 18 provided at the connection end of the outer handrail 11 and the inner handrail 12 with the support 1 to the bracket 8 fixed to the support 1. Fixed to connect non-rotatably. Thus, when the outer handrail 11 and the inner handrail 12 are connected and fixed to the support 1 via the connection bosses 17 and 18, the outer handrail 11 and the inner handrail 12 are properly fixed by the connection bosses 17 and 18 fixed to the support 1. By supporting it, the structural strength of the outer handrail 11, the inner handrail 12 and the support 1 can be enhanced to improve the safety of the handrail.

  When the switching mechanism 13 is provided on the outer handrail 11 and the lock mechanism 14 is provided on the inner handrail 12 and the middle portion of the fixed frame 15 is guided and supported by the guide body 74 fixed to the inner handrail 12, the lock mechanism 14 rattles in the radial direction. It is possible to extend and retract the handrails 11 and 12 in a stable state by restraining Further, when the handrails 11 and 12 are extended to the limit, the guide body 74 receives the lock mechanism 14 and functions as a stopper, so that the handrails 11 and 12 are erroneously separated and operated. It can prevent.

  When the operating head 37b of the operating shaft 37 fixed to the first bevel gear 22 faces the outer surface of the handrail 2 through the operating window 41 of the base block 21, the operating head 37b is used unless the operating tool 40 is used. Since the rotation operation can not be performed, the operation shaft 37 can be prevented from being rotated by mischief.

It is a partially broken front view of the handrail concerning the present invention. It is a front view of a support and a handrail which shows the example of use of a handrail. It is a top view of a handrail. It is an exploded plan view of a handrail. It is a disassembled perspective view of a switching mechanism. It is the sectional view on the AA line in FIG. It is the BB sectional drawing in FIG. It is an exploded perspective view of a lock mechanism. It is the CC sectional view taken on the line in FIG. It is the DD sectional view taken on the line in FIG. It is a partially broken plan view which shows the connection structure of a handrail and a support | pillar. It is a cross-sectional top view which shows operation | movement of a locking mechanism. It is a longitudinal cross-sectional front view which shows the state which the 1st bevel gear switched to the transmission cancellation | release attitude | position.

(Example) The Example of the handrail which concerns on this invention is shown in FIGS. In the present invention, front / rear, left / right, upper / lower follow the arrow shown in FIGS. 1 to 3 and the front / rear, left / right, upper / lower indication described in the vicinity of each arrow. In FIG. 2, the code | symbol 1 is a support | pillar fixedly fixed between a ceiling and a floor surface, and the handrail 2 which concerns on this invention is connectingly fixed between adjacent support | pillars 1. As shown in FIG. The column 1 has a ceiling-side pipe 3 and a floor-side pipe 4 which are relatively slidably inserted and connected, a ceiling base 5 mounted on the upper end of the ceiling-side pipe 3, and a floor base mounted on the lower end of the floor-side pipe 4 A telescopic locking member 7 or the like is provided at a connecting portion of the floor side pipe 4 and the ceiling side pipe 3 of the floor side pipe 4. A bracket 8 for connecting the handrail 2 is fastened and fixed to a midway portion of the floor side pipe 4. The ceiling-side pipe 3 and the floor-side pipe 4 are each formed of a round pipe made of aluminum, and after adjusting the insertion amount of both pipes 3 and 4, swing the lock lever 9 of the extensible locking tool 7 Thus, the ceiling-side pipe 3 and the floor-side pipe 4 can be supported so as not to move.

(Handrail structure)
In FIG. 3 and FIG. 4, the handrail 2 is accommodated inside the inner handrail 12 and the switching mechanism 13 fixed to the connection end of the outer handrail 11 and the inner handrail 12 of the nested structure and the support 1 of the outer handrail 11. A lock mechanism 14, a fixed frame 15 connecting the two mechanisms 13 and 14, and a switching shaft 16 for transmitting the switching operation of the switching mechanism 13 to the lock mechanism 14 are provided. The connection bosses 17 and 18 are respectively fixed to the connection ends of the outer handrail 11 and the inner handrail 12 with the column 1, and the connection bosses 17 and 18 are fastened and fixed to the bracket 8, thereby the outer handrail 11 and the inside The handrail 12 is integrated with the support 1.

  The outer handrail 11 and the inner handrail 12 are each made of a composite material in which a wood decorative resin layer is coated on the circumferential surface of an aluminum pipe member having a circular cross section, and a cap 19 is attached to the outer end of the outer handrail 11 connected to the inner handrail 12. It is fixed in place. By providing the cap 19, the level difference between the handrails 11 and 12 can be changed gradually, and while using the handrail 2 with a nested structure, a feeling of use close to a rod-like handrail can be exhibited. On the inner surface of the inner handrail 12, a pair of fastening ribs 12a having a C-shaped cross section are integrally formed. The fixing frame 15 is made of an aluminum tube having a rectangular cross section, and connection holes 15a are opened in opposite walls at both ends (see FIG. 5).

(Switching mechanism)
5 to 7, the switching mechanism 13 includes a plastic base block 21 fixed to the end of the outer handrail 11, and a first bevel gear 22 and a second bevel gear 23 rotatably supported by the base block 21. A screw structure or the like for converting the rotational movement of the second bevel gear 23 into the reciprocating movement of the switching shaft 16 is provided. In FIG. 5, the base block 21 is composed of a pair of half blocks 21A and 21B divided by a plane passing through the rotation center axis of the second bevel gear 23. In the joint surfaces (division surfaces) of the blocks 21A and 21B, gear support concave portions 24 and 25 for rotatably supporting the bevel gears 22 and 23 are formed to be recessed, and between the two gear support concave portions 24 and 25 A gear tooth recess 26 for accommodating the meshing gear teeth is concavely formed in a crosswise L-shape.

  The joint surfaces of the blocks 21A and 21B are formed with five pins 27 and pin holes 28 which are positioned and engaged with each other, and are engaged with each other to fix the two half blocks 21A and 21B inseparably. Resilient engagement claws 29 and engagement holes 30 are formed. Adjacent to the gear support recess 25 supporting the second bevel gear 23, a connection recess 31 for connecting the fixed frame 15 is formed in a recessed shape, and a square engaging protrusion 32 engaged with the previous connection hole 15a on the recessed surface. Is formed. A nut body 33 is insert-fixed to the side end of each of the half blocks 21A and 21B, and another nut 34 is engaged with and attached to the opposing peripheral surface of each half block 21A and 21B (FIG. 4, See Figure 10).

  Each of the first bevel gear 22 and the second bevel gear 23 is made of an injection-molded product made of engineering plastic, and integrally includes a shaft portion and a gear tooth portion rotatably supported by the gear support concave portions 24 and 25 described above. The number of gear teeth of the first bevel gear 22 is set to twice the number of gear teeth of the second bevel gear 23. When the first bevel gear 22 makes one revolution, the second bevel gear 23 makes two revolutions. In this embodiment, the first bevel gear 22 and the second bevel gear 23 constitute a transmission structure of the switching mechanism 13.

  An operating shaft 37 is fixed to the first bevel gear 22 in a penetrating manner along the rotation center thereof. More specifically, as shown in FIG. 6, the screw shaft 37a of the operation shaft 37 is screwed into a metal female screw body 38 having a square external cross section fixed in the first bevel gear 22 and further projecting from the female screw body 38. The operating shaft 37 is integrated with the first bevel gear 22 by screwing a nut 39 onto a screw shaft 37a. The female screw body 38 and the nut 39 function as a double nut that prevents the operating shaft 37 from rotating relative to the first bevel gear 22.

  The operating shaft 37 is a bolt with a hexagonal hole, and the operating head (operating portion) 37 b is exposed on the upper surface of the first bevel gear 22. In order to rotate the operation head 37 b from the outer surface of the handrail 2 with a hexagonal rod wrench (operation tool) 40, an operation window 41 is opened in the peripheral wall of the base block 21 facing the gear tooth recess 26. That is, the operation head 37 b provided at the shaft end of the operation shaft 37 is exposed to the outer surface of the handrail 2 through the operation window 41 opened in the base block 21. As described above, when the operation head 37b of the operation shaft 37 fixed to the first bevel gear 22 faces the outer surface of the handrail 2 through the operation window 41 of the base block 21, the operation is performed unless the operation tool 40 is used. Since the head 37b can not be rotated, the operating shaft 37 can be prevented from being rotated by tampering.

  The screw structure provided between the second bevel gear 23 and the switching shaft 16 has a metal screw body 44 made of metal and having a square outer cross section fixed to the second bevel gear 23 and a screw shaft formed at the axial end of the switching shaft 16. It consists of a part 45. When the second bevel gear 23 is rotated by the first bevel gear 22, the switching shaft 16 is moved to either the left or right to transmit the switching operation of the switching mechanism 13 to the lock mechanism 14. The screw hole of the female screw body 44 and the screw shaft 45 are formed by right-handed screws.

  The base of the first bevel gear 22 is to prevent the first bevel gear 22 from being rotationally operated with excessive operating force and crushing the gear teeth of both gears 22 and 23 meshing with each other and the thread of the female screw 44 and the switching shaft 16. A block 21 supports reciprocating movement. Specifically, the first bevel gear 22 is in a transmission posture (the state shown in FIG. 6) in which the gear 22 meshes with the second bevel gear 23 and a transmission release posture (the one in FIG. 13) that releases the meshing state with the second bevel gear 23. Slide-guided by the gear support recess 24 so as to be able to move back and forth between In addition, the first bevel gear 22 is moved and urged in the direction of holding the transmission posture by the limit spring 46 disposed between the gear 22 and the upper wall of the gear tooth recess 26. Since the limit spring 46 is formed of a corrugated spring, the switching mechanism can be minimized by minimizing the space for accommodating the limit spring 46 despite the ability to move and bias the first bevel gear 22 with a greater spring force. 13 can be made compact.

(Locking mechanism)
As shown in FIGS. 8 and 9, the lock mechanism 14 is engaged by a fixed cam block 51 fixed to the end of the fixed frame 15, an end block 52 fixed to the axial end of the switching shaft 16, and an end block 52. A pair of movable cam blocks 53 which are integrally supported and move in the same direction as the block 52 are provided.

  The fixed cam block 51 is a rod-shaped plastic molded product having a cross section of a weight-shaped rod, and has a rectangular cross section for connecting the fixed frame 15 therein and a cross section for connecting the end block 52. A connecting hole 55 is formed to communicate the two holes. In the lower half portion of the arc circumferential surface, there is formed a fixed cam body 56 having a pair of first inclined cam bodies 56A and a second inclined cam body 56B formed between the two cam bodies 56A. . The first inclined cam body 56A and the second inclined cam body 56B are formed as inclined cams inclined in opposite directions to each other. As shown in FIG. 9, the end portion of the fixed frame 15 is inserted to the back end of the frame connection hole 54, and the screw 57 screwed in from the peripheral surface of the fixed cam block 51 is engaged with the connection hole 15a. 51 are integrated with the fixed frame 15. The partial arc-shaped groove provided on the peripheral surface of the fixed cam block 51 avoids contact interference with the pair of fastening ribs 12 a provided on the inner surface of the inner handrail 12, and the fixed cam block also when the screw 57 is loosened. This is to prevent the rotation of the inner handrail 51 relative to the inner handrail 12.

  The end block 52 is integrally provided with an end boss 60 having an oval cross section which is fastened and fixed to the axial end of the switching shaft 16 and a weight-shaped flange wall 61 which is formed so as to overhang on the fastening end side of the end boss 60. It consists of plastic moldings. On the inner lower half side of the end boss 60, a female screw body 62 made of metal and having a rectangular outer cross section is insert-fixed, and the screw shaft portion 63 of the switching shaft 16 is screwed into the female screw body 62. The end block 52 is integrated with the switching shaft 16 by screwing the nut 64 into the protruding screw shaft portion 63. The female screw body 62 and the nut 64 function as a double nut that prevents the end block 52 from rotating relative to the switching shaft 16. The flange wall 61 is formed with a pair of elongated holes 65 which are long in the radial direction. The reason why the flange wall 61 is formed in a weight shape is to prevent contact interference with the fastening rib 12 a as in the fixed cam block 51 and to prevent the end block 52 from rotating relative to the inner handrail 12. .

  The movable cam block 53 is formed on a friction lock wall 68 having a partial arc shape in cross section to be crimped to the inner surface of the inner handrail 12, a movable cam body 69 formed on the inner surface of the wall 68, and a side end inner surface of the friction lock wall 68. It is made of a plastic molding integrally provided with a partial ring-shaped interlocking wall 70 which is formed in an overhanging manner. The movable cam body 69 corresponds to the fixed cam body 56, and includes a pair of first inclined cam bodies 69A and a second inclined cam body 69B formed between the two cam bodies 69A. The first inclined cam body 69A and the second inclined cam body 69B are formed as inclined cams which are inclined in opposite directions to each other.

  The pair of first inclined cam bodies 69A and the interlocking wall 70 are opposite to each other with a gap therebetween, and the flange wall 61 of the end block 52 engaged with the clearance portion is the first inclined cam body 69A and the interlocking wall 70 Sandwiching The interlocking wall 71 is formed with an interlocking projection 71 that engages with the elongated hole 65. As described above, by sandwiching the flange wall 61 between the first inclined cam body 69A and the interlocking wall 70, the pair of movable cam blocks 53 can move along with the end block 52. Further, the pair of movable cam blocks 53 can be expanded and contracted in the radial direction with respect to the end block 52 through the engagement structure (long hole 65 and interlocking projection 71) provided between the flange wall 61 and the interlocking wall 70 It is connected. According to the lock mechanism 14, after the fixed cam block 51 is fixed to the fixed frame 15 and the end block 52 is fixed to the switching shaft 16, the pair of movable cam blocks 53 is engaged with and coupled to the end block 52. Then, the lock mechanism 14 can be assembled. Therefore, it is possible to carry out a series of assembly operations in a reliable and easy manner while viewing.

  In FIG. 4, a guide body 74 for guiding and supporting the middle portion of the fixed frame 15 is fixed to the connection end of the inner handrail 12 with the outer handrail 11. The guide body 74 is made of a plastic molding integrally provided with a fitting shaft portion 75 having a weight-shaped cross section and a flange wall 76, and a guide groove 77 for guiding the fixing frame 15 is formed in the central portion thereof. The guide shaft 74 is inserted by inserting the fitting shaft portion 75 into the inner handrail 12 and screwing the screw 78 inserted into the flange wall 76 into the fastening rib 12 a in a state where the flange wall 76 abuts against the end of the inner handrail 12. Is fixed to the inner handrail 12. As described above, when the guide frame 74 fixed the middle part of the fixed frame 15 to the inner handrail 12 guides and supports it, the lock mechanism 14 prevents the rattling in the radial direction and the two handrails 11 and 12 are always stable. It can expand and contract. In addition, when the handrails 11 and 12 are extended to the limit, the guide body 74 receives the lock mechanism 14 and functions as a stopper, thereby reliably preventing the two handrails 11 and 12 from being separated by mistake. it can.

  The connection boss 17 of the outer handrail 11 is made of a cylindrical plastic molded product having both ends open, and a cap hole 81 (see FIG. 6) externally fitted to the base block 21 and a bracket 8 fixed to the support 1 A fastening hole 82 to be connected is formed. With the connection boss 17 fitted on the base block 21, a tool hole 83 for inserting a hexagonal bar wrench 40 is opened in the peripheral wall of the cap hole 81 facing the operation window 41 of the base block 21. . Further, on the inner surface of the fastening hole 82, an engaging groove 84 to be engaged with the bracket 8 is formed, and a bolt insertion hole 85 is formed on the opposite surface of the groove 84. The cap hole 81 and the fastening hole 82 are divided by the dividing wall 86, and the dividing wall 86 is formed with a pair of screw holes. The connection boss 18 of the inner handrail 12 basically has the same structure as the connection boss 17 of the outer handrail 11, but a point where the diameter of the boss is slightly smaller and a point where the tool hole 83 is not formed is a connection for the outer handrail 11 It is different from the boss 17.

  The handrail 2 configured as described above is assembled according to the following procedure, and then the connection bosses 17 and 18 at both ends thereof are connected to the bracket 8 to be integrated with the support 1. First, as shown in FIG. 4, the switching mechanism 13 and the locking mechanism 14 are connected by the fixed frame 15 and the switching shaft 16 to form an operation unit. For example, after assembling the first bevel gear 22, the second bevel gear 23, the limit spring 46, etc. on one half block 21B, the screw shaft 45 is screwed into the female screw 38, and the switching shaft 16 is switched to the switching mechanism 13 Unify. Furthermore, the fixed frame 15 externally fitted to the switching shaft 16 is engaged with and attached to the connecting recess 31, and the fixed frame 15 is integrated with the switching mechanism 13. In this state, the other half-split block 21A is assembled to the half-split block 21B to integrate the half-split blocks 21A and 21B. As described above, when the base block 21 is configured by the pair of half blocks 21A and 21B, the first and second bevel gears 22 and 23, the limit spring 46, the fixing frame 15 and the like can be divided into one half block 21B. Since the other half-split block 21A may be joined to the first half-split block 21B after temporary assembly, a series of assembly operations can be carried out easily and accurately while visually checking.

  Next, with the fixed cam block 51 temporarily assembled to the fixed frame 15 and the female screw body 62 of the end block 52 being screwed into the screw shaft portion 63 of the switching shaft 16, the operating shaft 37 is rotated by the hexagonal rod wrench 40 Then, the end boss 60 of the end block 52 is drawn into and engaged with the connection hole 55. In this state, as shown in FIG. 9, the screw 57 is screwed in from the opposite surface of the fixed cam block 51, and the fixed frame 15 and the fixed cam block 51, and the switching shaft 16 and the end block 52 are integrated inseparably. Furthermore, the flange wall 61 of the end block 52 is sandwiched between the fixed cam body 56 of the pair of movable cam blocks 53 and the interlocking wall 70, and the pair of movable cam blocks 53 is integrated with the end block 52. Each part leading to the lock mechanism 14 is made into an operation unit.

  The lock mechanism 14 of the obtained operation unit is inserted into the inner handrail 12 and fitted in the inner handrail 12 with the guide groove 77 of the guide body 74 engaged with the fixed frame 15. The operation unit can be integrated with the inner handrail 12 by screwing the screw 78 (see FIG. 4) inserted into the flange wall 76 into the fastening rib 12a. In this state, the outer handrail 11 to which the cap 19 is attached is externally fitted to the inner handrail 12 from the side of the open end of the inner handrail 12, and the insertion start end is externally fitted to the base block 21. 11 can be temporarily connected to the inner handrail 12; As shown in FIG. 10, the screw insertion hole 89 is opened in the cylindrical wall of the insertion start end of the outer handrail 11, so the screw 90 inserted into the screw insertion hole 89 is provided on the circumferential surface of the base block 21. By screwing into the nut 34, the base block 21 and the outer handrail 11 can be integrated.

  Since the side end portion of the base block 21 in the above state is exposed to the outside of the insertion start end of the outer handrail 11, as shown in FIG. 11, the cap hole 81 of the connection boss 17 is externally fitted in the exposed portion. The tool hole 83 of the connection boss 17 is made to face the operation window 41 of the base block 21. Then, the connection boss 17 is integrated with the base block 21 and the outer handrail 11 by screwing a pair of screws 92 inserted into the screw holes of the dividing wall 86 into the nut body 33 of the base block 21. Similarly, the handrail 2 can be completed by externally fitting the cap hole 81 of the connection boss 18 to the inner handrail 12 and screwing the pair of screws 93 inserted into the screw holes of the section wall 86 into the fastening rib 12a. The handrail 2 is shipped from the factory with the outer handrail 11 and the inner handrail 12 being the shortest.

  At the time of construction of the handrail 2, first of all, depending on the situation of the construction site, the pole 1 is not supported by, for example, an outlet provided on the wall, or is fixed by tension in relation to the position of the bed installed in the living room. Next, for example, as shown in FIG. 11, the engagement groove 84 of the connection boss 17 on the outer handrail 11 side is engaged with the bracket 8 of the support 1 and the screw 94 inserted into the bolt insertion hole 85 is a screw hole of the bracket 8 The outer handrail 11 is non-rotatably connected to one of the columns 1 by being screwed into the shaft 1. In this state, the inner handrail 12 is pulled out of the outer handrail 11, and the connection boss 18 is non-rotatably fastened to the other support post 1 with a screw 94 in the same manner as the previous connection boss 17. Since the outer handrail 11 and the inner handrail 12 in this state can extend and contract, it is confirmed that each adjacent column 1 is vertical, and then the operating shaft 37 of the switching mechanism 13 is rotated by the hexagonal rod wrench 40 Thus, the movable cam block 53 of the lock mechanism 14 is switched to the lock posture. As described above, when the outer handrail 11 and the inner handrail 12 are connected and fixed to the support 1 via the connection bosses 17 and 18, the connection bosses 17 and 18 for fixing the outer handrail 11 and the inner handrail 12 to the support 1 properly By fixing and supporting, the structural strength of the outer handrail 11 and the inner handrail 12 and the support 1 can be enhanced to improve the safety of the handrail.

  In FIG. 6, when the operation shaft 37 is rotated clockwise by the hexagonal rod wrench 40, the first bevel gear 22, the second bevel gear 23, and the female screw 44 rotate clockwise about the central axes of the gears 22 and 23. At this time, the end of the switching shaft 16 on the side of the lock mechanism 14 is fixed to the end block 52 so as not to be relatively rotatable, and the block 52 is held by the fixed cam block 51 so as not to rotate. Is drawn to the right in FIG. As the switching shaft 16 moves to the right, the end block 52 and the movable cam block 53, which have been held in the unlocked position, move in the arrow R direction (right direction) in FIG. As described above, when the switching shaft 16 moves in the right direction (when the switching shaft 16 moves forward), the first tilt cam bodies 56A and 69A expand the moving motion of the switching shaft 16 as the movable cam block 53 Convert to open operation.

  As a result, since the movable cam body 69 of the movable cam block 53 contacts and rides on the fixed cam body 56 of the fixed cam block 51, the movable cam block 53 moves radially outward while moving in the axial center direction of the handrail 2. Move to switch to lock position. In the movable cam block 53 in this state, the pair of first inclined cam surfaces 69A of the movable cam body 69 receives the wedge action of the pair of first inclined cam bodies 56A of the fixed cam body 56 and the inner surface of the inner handrail 12 is strongly The outer handrail 11 and the inner handrail 12 are locked so as not to slide relative to each other because they are pressed. The lock mechanism 14 rotates the second bevel gear 23 and the female screw body 3 three times when the operation shaft 37 is rotated about a half turn with the hexagonal rod wrench 40. It can move and switch from the unlocked position to the locked position.

  As described above, even if the lock mechanism 14 is switched to the lock position, the movable cam block 53 can not move further to the right when the hexagonal rod wrench 40 is further rotated, so both bevel gears of the switching mechanism 13 An excessive operating force is applied to the 22.23 meshing tooth surface and the screw portion of the screw structure. In order to avoid such a situation, the first bevel gear 22 is moved and urged toward the transmission position by the limit spring 46.

  When a large operating force acts on the meshing tooth surfaces of the two bevel gears 22 and 23, the first bevel gear 22 receiving the meshing reaction force separates from the second bevel gear 23 while crushing and deforming the limit spring 46 as shown in FIG. The gear teeth of the first bevel gear 22 ride over the gear teeth of the second bevel gear 23 and idle. As described above, in a situation where the operation moment of the hexagonal rod wrench 40 acting on the first bevel gear 22 exceeds the appropriate value, the first bevel gear 22 switches to the transmission release posture against the biasing force of the limit spring 46 and idles. Therefore, it is possible to reliably prevent the gear teeth and threads from being deformed and crushed. The fact that the first bevel gear 22 is idle means that the first bevel gear 22 receives the spring force of the limit spring 46 at the same time as the gear teeth of the first bevel gear 22 get over the gear teeth of the second bevel gear 23. It is possible to clearly know by switching to the transmission position and generating a loud tapping sound.

  Depending on the worker, in FIG. 6, the operating shaft 37 may be turned counterclockwise by the hexagonal rod wrench 40. In that case, the switching shaft 16 is pushed leftward as viewed in FIG. As the switching shaft 16 moves to the left, the end block 52 and the movable cam block 53, which have been held in the unlocked position, move in the arrow L direction (left direction) in FIG. In this case, the second inclined cam body 69B at the center of the movable cam block 53 is strongly pressed against the inner surface of the inner handrail 12 by the wedge action of the second inclined cam body 56B at the center of the fixed cam body 56. The outer handrail 11 and the inner handrail 12 are locked so as not to slide relative to each other. As described above, when the switching shaft 16 moves in the left direction (when the switching shaft 16 moves in the backward direction), the second tilt cam bodies 56B and 69B expand the moving motion of the switching shaft 16 as the movable cam block 53 Convert to open operation.

  As described above, the lock mechanism 14 equally changes from the unlocking posture to the locking posture in either the case where the operating shaft 37 of the switching mechanism 13 is rotated clockwise or the case where the operating shaft 37 is rotated counterclockwise. It is possible to lock and fix the handrails 11 and 12 by switching. Therefore, the operator can simply rotate the operation shaft 37 to either the left or the right with the hexagonal rod wrench 40, so that the lock fixing operation of the two handrails 11 and 12 can be performed easily. Even when the operating shaft 37 is rotated counterclockwise and a large operating force is applied to the meshing tooth surface of both bevel gears 22 and 23, the first bevel gear 22 is switched to the transmission release attitude as described above. Since the idle rotation is performed, it is possible to reliably prevent the gear teeth and threads from being deformed and crushed.

  In the handrail 2 according to the above embodiment, the rotation center of the operation shaft 37 rotated by the hexagonal rod wrench 40 is converted to the direction orthogonal to the pair of bevel gears 22 and 23, and the rotation operation is converted to reciprocation operation by the screw structure. Thus, the switching shaft 16 can be moved in the left and right direction. In such a switching mechanism 13, only by operating the operation shaft 37 fixed to the first bevel gear 22 with the operation tool 40, the rotation center axis is converted to a direction along the center of the outer handrail 11 by the pair of bevel gears 22 and 23, Furthermore, it can be converted to the reciprocating motion of the switching shaft 16 by a screw structure. That is, since the rotational movement of the operation tool 40 can be reliably converted to the reciprocating movement of the switching shaft 16 while minimizing the number of parts required for the movement conversion, the entire structure of the switching mechanism 13 is simplified and expansion and contraction adjustment is possible Can be provided at lower cost. In addition, since it is only necessary to rotate the switching mechanism 13 in a predetermined direction with the operation tool 40 in a state where the outer handrail 11 and the inner handrail 12 are extended and contracted to an arbitrary adjustment position, the installation work of the handrail 2 Anyone can do it easily.

  In a state in which the reciprocating movement of the switching shaft 16 is moved by the switching mechanism 13, the end block 52 and the movable cam block 53 are reciprocated along the switching shaft 16 with respect to the fixed cam block 51 supported by the fixed frame 15. Thus, the movable cam block 53 can be switched to the lock posture and the lock release posture. According to the lock mechanism 14, by rotating the first bevel gear 22 with the operation tool 40, the movable cam block 53 can be moved relative to the fixed cam block 51 and switched to the lock posture. Further, the movable cam block 53 can not be returned to the unlocked position unless the first bevel gear 22 is rotated by the operation tool 40 in the reverse direction. Therefore, even when a large external force acts on the outer handrail 11 or the inner handrail 12, it is possible to reliably prevent the movable cam block 53 from switching to the unlocking posture, and to further enhance the safety of the handrail 2 capable of expansion and contraction. It can be improved.

  Further, since the rotational movement of the operating shaft 37 is converted into the reciprocating movement by the screw structure provided in the switching structure 13, the movable cam block 53 is switched to the unlocking attitude unless the operating shaft 37 is rotated by the hexagonal rod wrench 40. There is nothing to do. For example, even when the position of the care recipient who is walking while holding the handrail 2 breaks down and a large external force acts on the outer handrail 11 and the inner handrail 12, the locking posture of the movable cam block 53 is maintained. Continue to support the care recipient with certainty. In addition, even if the external handrail 11 and the inner handrail 12 receive an impact force in the expansion / contraction direction or an external force in the rotation direction, the movable cam block 53 is locked because the entire operation unit is accommodated inside the handrail 2 It is possible to provide the handrail 2 excellent in safety, which can reliably prevent the lock mechanism 14 from being unlocked by mistake without switching to the release position.

The handrail 2 configured as described above can be implemented in the following manner.
The switching mechanism 13 fixed to the connection end of the outer handrail 11 and the inner handrail 12 of the nested structure disposed between the adjacent columns 1 and 1 and the column 1 of either handrail 11 and the other handrail 12 And a lock mechanism 14 supported by a fixed frame 15 fixed to the switching mechanism 13. The outer handrail 11 and the inner handrail 12 are each non-rotatably connected to the support 1. The switching mechanism 13 includes a transmission structure rotated by the operation tool 40 from the outer surface of the handrail 11 and a screw structure converting a rotational movement of the transmission structure into a reciprocating movement.
The switching mechanism 13 and the locking mechanism 14 are connected by a switching shaft 16 that transmits the reciprocating motion converted by the screw structure to the locking mechanism 14. The lock mechanism 14 is provided with a movable cam block 53 which is operated to be displaced between a lock posture in which it is crimped to the inner surface of the other handrail 12 in response to the reciprocation of the switching shaft 16 and a lock release posture. In a state where the outer handrail 11 and the inner handrail 12 are extended and contracted to an arbitrary adjustment position, the movable cam block 53 is switched to the lock posture by rotating the switching mechanism 13 in a predetermined direction by the operation tool 40. It is characterized in that it adheres closely to the inner surface of the other handrail 12 and the handrails 11 and 12 can be locked so as not to be stretchable.

  According to the handrail described above, since the rotational movement of the transmission structure is converted to reciprocating movement by the screw structure, the movable cam block 53 of the lock mechanism 14 is in the unlocking posture unless the switching mechanism 13 is rotated by the operation tool 40. It can not be switched. In addition, since the outer handrail 11 or the inner handrail 12 is non-rotatably connected to the support 1, the posture of the care recipient who is walking while holding the outer handrail 11 or the inner handrail 12 is broken. However, the movable cam block 53 does not switch to the unlocking posture. Therefore, it is a handrail that can be expanded and contracted, and even when a large external force acts on the outer handrail 11 and the inner handrail 12, it is surely prevented that the lock mechanism 14 is unlocked by mistake. Provide a handrail with excellent safety that can support the

  Other than the above embodiment, it is not necessary to provide a pair of movable cam blocks 53, and at least one may be provided. In that case, the fixed cam block 51 or the end block 52 is integrally provided with a sliding wall having a partial arc shape in cross section that is in sliding contact with the inner surface of the inner handrail 12. It is good to receive it on the moving wall. The switching mechanism 13 can be provided on the inner handrail 12 side, and the lock mechanism 14 can be provided on the outer handrail 11 side. The handrail 2 can be connected to the support 1 in a diagonally intersecting state. Only one of the first inclined cams 56A and 69A and the second inclined cams 56B and 69B is formed on the fixed cam 56 of the fixed cam block 51 and the movable cam 69 of the movable cam block 53. May be In that case, it is preferable to provide in the vicinity of the tool hole 83 an index indicating the rotational direction in which the lock mechanism 14 switches to the lock posture. The transmission structure of the switching mechanism 13 does not have to be formed of a bevel gear, and can be formed of a bevel gear, a hypoid gear, a face gear, a spiral gear or the like.

Reference Signs List 1 post 2 handrail 11 outer handrail 12 inner handrail 13 switching mechanism 14 lock mechanism 15 fixed frame 16 switching shaft 21 base block 22 first bevel gear 23 second bevel gear 37 operation shaft 40 operation tool (hexagonal rod wrench)
41 operation window 46 limit spring 51 fixed cam block 52 end block 53 movable cam block 56 fixed cam body 69 movable cam body

Claims (10)

Fixed at the connecting end of the nested outer handrail (11) and the inner handrail (12) arranged between the adjacent columns (1.1) and the column (1) of one of the handrails (11) A lock mechanism (14) housed inside the other handrail (12) and supported by a fixed frame (15) fixed to the switch mechanism (13),
The outer handrail (11) and the inner handrail (12) are each connected non-rotatably to the column (1),
The switching mechanism (13) includes a transmission structure rotated by the operation tool (40) from the outer surface of the handrail (11), and a screw structure converting the rotational movement of the transmission structure into a reciprocating movement.
The switching mechanism (13) and the locking mechanism (14) are connected by a switching shaft (16) that transmits the reciprocating motion converted by the screw structure to the locking mechanism (14),
The lock mechanism (14) receives the reciprocation of the switching shaft (16), and the movable cam block (53) is operated to be displaced between the lock posture to be crimped to the inner surface of the other handrail (12) and the lock release posture. )),
In the state where the outer handrail (11) and the inner handrail (12) are extended and contracted to an arbitrary adjustment position, the movable cam block (the movable cam block (13) is operated in a predetermined direction by the operation tool (40). 53) A handrail characterized by switching to the lock position and intimately adhering to the inner surface of the other handrail (12) so that the handrail (11 12) can be locked so as not to extend and contract. The switching mechanism (13) comprises a base block (21) fixed inside the one handrail (11), a first bevel gear (22) rotatably supported by the base block (21), and a second bevel gear (23) and a screw structure provided between the second bevel gear (23) and the switching shaft (16),
By rotating the operation shaft (37) fixed to the first bevel gear (22) with the operation tool (40), the rotation center axis is oriented along the center of the handrail (11) by the pair of bevel gears (22, 23) The handrail according to claim 1, wherein the handrail is converted into a reciprocating motion of the switching shaft (16) by means of a screw structure. The lock mechanism (14) comprises a fixed cam block (51) fixed to the fixed frame (15), an end block (52) fixed to the axial end of the switching shaft (16), and an end block (52). And a movable cam block (53) that moves in the same direction as the block (52).
The fixed cam body (56) and the movable cam block (53) and the movable cam block (53) contact or separate from each other to expand and contract the movable cam block (53) between the locking attitude and the unlocking attitude The body (69) is formed,
The movable cam block (53) moves relative to the fixed cam block (51) by switching the first bevel gear (22) in a predetermined direction with the operating tool (40), and switches to the lock posture. Handrail described in 2. The first bevel gear (22) can reciprocate between the transmission attitude in which the base block (21) meshes with the second bevel gear (23) and the transmission cancellation attitude in which the second bevel gear (23) disengages. Supported and biased to move in a direction to maintain the transmission position by a limit spring (46) disposed between the first bevel gear (22) and the base block (21),
When the operation moment of the operation tool (40) acting on the first bevel gear (22) exceeds the appropriate value, the first bevel gear (22) is switched to the transmission release posture against the biasing force of the limit spring (46). The handrail according to claim 2 or 3 which idles. The first inclined cam body (56A, 69A) converts the forward movement of the switching shaft (16) into the widening operation of the movable cam block (53) on the opposing surface of the fixed cam block (51) and the movable cam block (53). And a second inclined cam body (56B, 69B) for converting the return movement of the switching shaft (16) into the expansion movement of the movable cam block (53),
Even if the rotation operation direction of the operation tool (40) is either rightward or leftward, the movable cam block (53, 53) can be expanded by the fixed cam block (51) and switched to the lock posture The handrail according to claim 3 or 4. The base block (21) is composed of a pair of half blocks (21A and 21B) divided by a plane passing through the rotation center axis of the second bevel gear (23),
The first bevel gear (22) and the second bevel gear (23) are rotatably supported by the gear support recesses (24, 25) formed in the joint surfaces of the pair of half blocks (21A, 21B) and fixed The handrail according to any one of claims 2 to 5, wherein 15) is engaged with and engaged with a connecting recess (31) formed by recessing on the joint surface of the pair of half blocks (21A, 21B). The lock mechanism (14) is provided with a pair of movable cam blocks (53, 53) facing each other with the fixed cam block (51) in between,
The end block (52) integrally includes an end boss (60) fastened and fixed to the shaft end of the switching shaft (16), and a flange wall (61) formed so as to overhang on the fastening end side peripheral surface of the end boss (60). Have
The pair of movable cam blocks (53, 53) includes a friction lock wall (68) crimped to the inner surface of the other handrail (12) and a movable cam body (69) formed on the inner surface of the wall (68). An interlocking wall (70) integrally formed on the inner surface of the friction lock wall (68) and sandwiching the flange wall (61) of the end block (52) in cooperation with the movable cam body (59); ,
The fixed cam block (51) is provided with a pair of fixed cam bodies (56) corresponding to the movable cam body (69),
The movable cam block (53, 53) is movably connected to the end block (52) via the movable cam body (59) and the interlocking wall (70) sandwiching the flange wall (61), and the flange wall The handrail according to any one of claims 3 to 6, wherein the handrail is connected so as to be capable of expanding and contracting in the radial direction via an engaging structure provided between the (61) and the interlocking wall (70).   Connecting bosses (17, 18) are provided at the connecting end of the outer handrail (11) and the inner handrail (12) with the support (1), and each connecting boss (17, 18) is fixed to the support (1) The handrail according to any one of claims 1 to 7, wherein the outer handrail (11) and the inner handrail (12) are non-rotatably connected and fixed to the support column (1) by fastening and fixing to the bracket (8). The switching mechanism (13) is fixed to the connection end of the outer handrail (11) with the column (1), and the lock mechanism (14) is accommodated inside the inner handrail (12),
The middle part of the fixed frame (15) is slidably guided and supported by a guide body (74) fixed to the connection end of the inner handrail (12) with the outer handrail (11),
A handrail according to any one of the preceding claims, wherein the guide body (74) doubles as a stopper which defines the extension limits of the outer handrail (11) and the inner handrail (12). The operating shaft (37) is fixed in a penetrating manner along the central axis of the first bevel gear (22),
The operating head (37b) provided at the shaft end of the operating shaft (37) faces the outer surface of the handrail (2) through the operating window (41) opened in the base block (21) The handrail described in any one of 9.

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