TECHNICAL FIELD
[0001] The present invention relates to an elevator safety apparatus that can brake running
of a car in either vertical direction.
BACKGROUND ART
[0002] Conventionally, elevator apparatuses have been proposed that include a wedge-type
emergency stop device in which braking is activated electrically if an elevator abnormality
has occurred. In these conventional elevator apparatuses, a braking force is applied
to a car by displacing a wedge using an electromagnetic actuator to engage the wedge
between a guide rail that guides the car and a bracket that is disposed on the car
(see Patent Literature 1, for example).
[0003] Conventionally, elevator safety apparatuses have also been proposed that perform
the car braking action by combining actions of a pair of electromagnets to pivot a
pivoting member vertically. A top braking shoe and a bottom braking shoe are disposed
on the pivoting member. A guide rail that guides the car is gripped between the bottom
braking shoe and a fixed shoe by upward pivoting of the pivoting member, and is gripped
between the top braking shoe and the fixed shoe by downward pivoting of the pivoting
member. The car is braked by the guide rail being gripped between either the top braking
shoe or the bottom braking shoe and the fixed shoe (see Patent Literature 2, for example).
[0004]
[Patent Literature 1]
W02004/083091
[Patent Literature 2]
European Patent Application Publication No. 1460020 (Specification)
DISCLOSURE OF THE INVENTION
PROBLEM TO BE SOLVED BY THE INVENTION
[0005] However, in the elevator apparatus that is disclosed in Patent Literature 1, a plurality
of emergency stop devices that perform a braking action individually either in an
upward direction or in a downward direction must be mounted to the car. Consequently,
in order to perform a braking action on the car in either vertical direction, the
emergency stop device as a whole is enlarged.
[0006] In the elevator safety apparatus that is disclosed in Patent Literature 2, because
a pair of electromagnets must be used in order to pivot the pivoting member, the drive
portion is also enlarged.
[0007] The present invention aims to solve the above problems and an object of the present
invention is to provide an elevator safety apparatus that can achieve reductions in
size, and that can perform a car braking action in either vertical direction more
reliably and in a shorter amount of time.
MEANS FOR SOLVING THE PROBLEM
[0008] In order to achieve the above object, according to one aspect of the present invention,
there is provided an elevator safety apparatus characterized in including: a housing
that is supported by a car that is guided by a guide rail, and that is displaceable
horizontally relative to the car; a bearing rail stopper that is disposed on the housing;
a pivoting rail stopper that is disposed on the housing such that the guide rail is
disposed between the pivoting rail stopper and the bearing rail stopper, and that
can be pivoted vertically such that a distance to the bearing rail stopper is reduced
by the vertical pivoting; and a displacement driving mechanism that displaces the
housing relative to the car in a direction in which the pivoting rail stopper separates
from and contacts with the guide rail, the guide rail being gripped between the pivoting
rail stopper and the bearing rail stopper by the pivoting rail stopper being pivoted
in a direction that corresponds to a direction of movement of the car while contacting
the guide rail.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
Figure 1 is a structural diagram that shows an elevator apparatus according to Embodiment
1 of the present invention;
Figure 2 is a structural diagram that shows an emergency stopping apparatus from Figure
1;
Figure 3 is a cross section that has been taken along line III - III in Figure 2;
Figure 4 is a side elevation of the emergency stopping apparatus in Figure 2;
Figure 5 is a structural diagram that shows a state in which a central contacting
surface of a pivoting rail stopper from Figure 2 contacts a car guide rail;
Figure 6 is a cross section that has been taken along line VI - VI in Figure 5;
Figure 7 is a structural diagram that shows a state in which a lower frictional surface
of the pivoting rail stopper from Figure 2 contacts the car guide rail;
Figure 8 is a cross section that has been taken along line VIII - VIII in Figure 7;
Figure 9 is a structural diagram that shows an emergency stopping apparatus according
to Embodiment 2 of the present invention;
Figure 10 is a cross section that has been taken along line X - X in Figure 9;
Figure 11 is a cross section that has been taken along line XI - XI in Figure 9;
Figure 12 is a structural diagram that shows a state in which a central contacting
surface of a pivoting rail stopper from Figure 9 contacts a car guide rail;
Figure 13 is a cross section that has been taken along line XIII - XIII in Figure
12;
Figure 14 is a structural diagram that shows a state in which a lower frictional surface
of the pivoting rail stopper from Figure 9 contacts the car guide rail; and
Figure 15 is a cross section that has been taken along line XV - XV in Figure 14.
BEST MODE FOR CARRYING OUT THE INVENTION
[0010] Preferred embodiments of the present invention will now be explained with reference
to the drawings.
Embodiment 1
[0011] Figure 1 is a structural diagram that shows an elevator apparatus according to Embodiment
1 of the present invention. In the figure, a car 1 and a counterweight (not shown)
are suspended by a main rope 2. The main rope 2 is wound around a drive sheave of
a hoisting machine. The drive sheave is rotated by a driving force from the hoisting
machine. The car 1 and the counterweight are raised and lowered inside a hoistway
by the rotation of the drive sheave. A pair of car guide rails 3 that guide raising
and lowering of the car 1, and a pair of counterweight guide rails (not shown) that
guide raising and lowering of the counterweight are installed in the hoistway.
[0012] The raising and lowering of the car 1 and the counterweight are controlled by an
elevator control board 4. Respective information from a car speed detecting sensor
5 that detects speed of the car 1, a door opening and closing detecting sensor 6 that
detects whether a doorway (not shown) of the car 1 is open or closed, and a main rope
breakage detecting sensor 7 that detects presence or absence of a breakage in the
main rope 2 is sent to the control board 4. An encoder, or a resolver, etc., that
generates a signal that corresponds to rotational speed of the drive sheave, for example,
can be used as the car speed detecting sensor 5. A position sensor, etc., that detects
the position of a door that opens and closes the doorway of the car 1, for example,
can be used as the door opening and closing detecting sensor 6. A tension detector,
etc., that detects tension of the main rope 2, for example, can be used as the main
rope breakage detecting sensor 7.
[0013] A braking command portion 8 that detects presence or absence of an elevator abnormality
based on respective information from the car speed detecting sensor 5, the door opening
and closing detecting sensor 6, and the main rope breakage detecting sensor 7 is disposed
on the control board 4. The braking command portion 8 outputs a braking command if
the occurrence of an elevator abnormality is detected.
[0014] The braking command portion 8 includes a computer that has: an arithmetic processing
portion (a CPU, etc.), a storage portion (ROM, RAM, hard disk, etc.), and a signal
input-output portion. The functions of the braking command portion 8 can be implemented
by arithmetic processing by the computer.
[0015] A pair of emergency stopping apparatuses 9 that constitute a braking apparatus that
brakes the car 1 by gripping the car guide rail 3 are mounted to the car 1. Each of
the emergency stopping apparatuses 9 performs a braking action that brakes the car
1 when a braking command is received from the braking command portion 8.
[0016] Figure 2 is a structural diagram that shows an emergency stopping apparatus 9 from
Figure 1. Figure 3 is a cross section that has been taken along line III - III in
Figure 2. In addition, Figure 4 is a side elevation of the emergency stopping apparatus
9 in Figure 2. In the figure, a mounting frame 10 is mounted to the car 1. An upper
guide rod 11 and a lower guide rod 12 that are disposed so as to be spaced apart from
each other vertically are mounted onto the mounting frame 10. The upper guide rod
11 and the lower guide rod 12 are disposed horizontally so as to be parallel to each
other.
[0017] A housing 13 is disposed inside the mounting frame 10. Sliding guides 13a through
13d are disposed above and below the housing 13. The upper guide rod 11 passes through
the sliding guides 13a and 13c. The lower guide rod 12 passes through the sliding
guides 13b and 13d. Thus, the housing 13 is slidable relative to the mounting frame
10 along the upper guide rod 11 and the lower guide rod 12. In other words, the housing
13 is displaceable horizontally relative to the car 1.
[0018] The housing 13 has: a housing main body 14; a mounting guide portion 15 that projects
from the housing main body 14 toward the car guide rail 3; and an adjusting bolt mount
portion 16 that projects from the housing main body 14 away from the car guide rail
3.
[0019] The mounting guide portion 15 is disposed in a position that is offset relative to
the car guide rail 3 in a direction of displacement of the housing 13. The mounting
guide portion 15 has: a bearing portion 15a that extends vertically; and a pair of
horizontal portions 15b and 15c that extend toward the car guide rail 3 from an upper
end portion and a lower end portion, respectively, of the bearing portion 15a.
[0020] A bearing rail stopper 17 and a pivoting rail stopper 18 that face each other from
opposite sides of the car guide rail 3 in a horizontal direction are disposed on the
housing 13. In other words, the car guide rail 3 is disposed between a bearing rail
stopper 17 and a pivoting rail stopper 18 that are disposed on a common housing 13.
Thus, the bearing rail stopper 17 and the pivoting rail stopper 18 are displaced together
with the housing 13. The bearing rail stopper 17 and the pivoting rail stopper 18
are both able to contact with and separate from the car guide rail 3 by displacement
of the housing 13 relative to the mounting frame 10.
[0021] The bearing rail stopper 17 is disposed between each of the horizontal portions 15b
and 15c. The bearing rail stopper 17 is guided along each of the horizontal portions
15b and 15c. A plurality of (in this example, two) shoulder bolts 19 that pass through
the bearing portion 15a are fixed to the bearing rail stopper 17. Each of the shoulder
bolts 19 is slidable horizontally relative to the bearing portion 15a. The bearing
rail stopper 17 is thereby displaceable horizontally relative to the housing 13.
[0022] Pressing elements 22 and adjusting elements 23 through which the respective common
shoulder bolts 19 are passed are disposed between the bearing rail stopper 17 and
the bearing portion 15a (i.e., on an opposite side of the bearing rail stopper 17
from the car guide rail 3).
[0023] The pressing elements 22 have a plurality of disk springs, for example. The pressing
elements 22 force the bearing rail stopper 17 toward the car guide rail 3 (i.e., away
from the bearing portion 15a) using elastic resilience due to the disk springs being
compressed. The adjusting elements 23 adjust the magnitude of the elastic resilience
of the pressing elements 22. In this example, the adjusting elements 23 have a plurality
of spacers that are stacked on each other. Adjustment of the magnitude of the elastic
resilience of the pressing elements 22 is performed by the adjusting the number of
spacers.
[0024] Each of the shoulder bolts 19 is passed through a washer 20, and is screwed into
a positioning nut 21. The washers 20 and the positioning nuts 21 can be engaged with
the bearing portion 15a. Displacement of the bearing rail stopper 17 toward the car
guide rail 3 is restricted by the engagement of the washers 20 and the positioning
nuts 21 with the bearing portion 15a. Adjustment of the position of the bearing rail
stopper 17 in a horizontal direction relative to the housing 13 is performed by adjusting
an amount of thread engagement of the positioning nuts 21 on the shoulder bolts 19.
[0025] When the bearing rail stopper 17 is displaced toward the bearing portion 15a, the
pressing elements 22 generate even larger elastic resilience in opposition to the
displacement of the bearing rail stopper 17.
[0026] The pivoting rail stopper 18 is mounted by means of a bearing 25 to a horizontal
shaft (a main shaft) 24 that is fixed to the housing main body 14. In this example,
the bearing 25 is a sliding bearing. The pivoting rail stopper 18 is thereby pivotable
vertically around the main shaft 24. If the pivoting rail stopper 18 contacts the
car guide rail 3 while the car 1 is moving, it is pivoted in a direction that that
corresponds to the direction of movement of the car 1 while contacting the car guide
rail 3. Specifically, when the pivoting rail stopper 18 contacts the car guide rail
3, the pivoting rail stopper 18 is pivoted upward if the car 1 is descending, and
the pivoting rail stopper 18 is pivoted downward if the car 1 is ascending.
[0027] The pivoting rail stopper 18 has a shape in which a distance to the bearing rail
stopper 17 is reduced continuously by the vertical pivoting. In other words, the distance
between the pivoting rail stopper 18 and the bearing rail stopper 17 is greatest before
pivoting of the pivoting rail stopper 18, and is reduced continuously as the amount
of pivoting of the pivoting rail stopper 18 increases.
[0028] The pivoting rail stopper 18 has: a pivoting rail stopper main body 26; and an upper
braking shoe 27 and a lower braking shoe 28 (a pair of braking shoes) that are disposed
on the pivoting rail stopper main body 26.
[0029] A rail contacting surface that the car guide rail 3 can contact is disposed on an
outer circumferential portion of the pivoting rail stopper main body 26 near the car
guide rail 3. The rail contacting surface has: a central contacting surface 26a; an
upper contacting curved surface (an upper curved surface portion) 26b that is a curved
surface that is contiguous with an upper end portion of the central contacting surface
26a; and a lower contacting curved surface (a lower curved surface portion) 26c that
is a curved surface that is contiguous with a lower end portion of the central contacting
surface 26a.
[0030] In this example, the central contacting surface 26a is a flat surface that is perpendicular
to a straight line in a radial direction that passes through a pivoting center Cn
of the pivoting rail stopper 18. The upper contacting curved surface 26b is a cylindrical
surface that is centered around a position Pup that is offset upward from the pivoting
center Cn. In addition, the lower contacting curved surface 26c is a cylindrical surface
that is centered around a position Pdn that is offset downward from the pivoting center
Cn. Moreover, the center Pup of the upper contacting curved surface 26b is positioned
near the Y-axis in a second quadrant of X - Y coordinates that are centered around
the center Cn, and the center Pdn of the lower contacting curved surface 26c is positioned
near the Y-axis in a third quadrant.
[0031] In this example, a coefficient of friction µ between the car guide rail 3 and each
of the contacting curved surfaces 26b and 26c is set so as to be greater than a ratio
γ (= LY/LX) between dimensions in a Y-axis direction LY between the respective centers
Pup and Pdn of each of the contacting curved surfaces 26b and 26c and the pivoting
center Cn and a dimension in the X-axis direction LX between a rail contacting point
of the pivoting rail stopper 18 and the center of rotation Cn (i.e., such that γ <
µ). Frictional force relative to the pressing force from the pivoting rail stopper
18 can thereby be made greater than return torque due to the pressing force from the
pivoting rail stopper 18 (a load that acts in an opposite direction from the direction
the pivoting rail stopper 18 should be pivoted during braking), enabling the pivoting
rail stopper 18 to be pivoted more reliably. In order to reduce the value of the dimensional
ratio γ, radius R of the cylindrical surfaces of each of the contacting curved surfaces
26b and 26c should be increased. Methods for increasing the coefficient of friction
µ include using a construction in which oil adhesion is prevented by guiding the car
guide rail 3 using an oilless guide or disposing a large number of minute lugs that
bite into the car guide rail 3 on each of the contacting curved surfaces 26b and 26c,
etc.
[0032] The upper braking shoe 27 is disposed so as to be adjacent to an upper end of the
upper contacting curved surface 26b. An upper frictional surface (an upper flat surface
portion) 27a that is a flat surface is disposed on the upper braking shoe 27. A portion
of the upper braking shoe 27 on which the upper frictional surface 27a is disposed
projects beyond the upper end of the upper contacting curved surface 26b by a predetermined
amount.
[0033] A spacer 45 that can adjust the amount of protrusion of the upper braking shoe 27
from the rail contacting surface is disposed between a back surface of the upper braking
shoe 27 and the pivoting rail stopper main body 26. Adjustment of the amount of protrusion
of the upper braking shoe 27 is performed by adjusting the thickness of the spacer
45.
[0034] The lower braking shoe 28 is disposed so as to be adjacent to a lower end of the
lower contacting curved surface 26c. A lower frictional surface (a lower flat surface
portion) 28a that is a flat surface is disposed on the lower braking shoe 28. A portion
of the lower braking shoe 28 on which the lower frictional surface 28a is disposed
projects beyond the lower end of the lower contacting curved surface 26c by a predetermined
amount.
[0035] A spacer 46 that can adjust the amount of protrusion of the lower braking shoe 28
from the rail contacting surface is disposed between a back surface of the lower braking
shoe 28 and the pivoting rail stopper main body 26. Adjustment of the amount of protrusion
of the lower braking shoe 28 is performed by adjusting the thickness of the spacer
46. In this example, the respective amount of protrusion of the upper braking shoe
27 and the lower braking shoe 28 from the rail contacting surface is approximately
identical.
[0036] The central contacting surface 26a contacts the car guide rail 3 due to displacement
of the pivoting rail stopper 18 toward the car guide rail 3.
[0037] If the central contacting surface 26a contacts the car guide rail 3 when the car
1 is descending, the pivoting rail stopper 18 is pulled by the car guide rail 3 so
as to be pivoted upward. As the pivoting rail stopper 18 is pivoted upward while placing
the lower contacting curved surface 26c in contact with the car guide rail 3, the
housing 13 is displaced in a direction in which the main shaft 24 moves away from
the car guide rail 3 (i.e., a direction in which the bearing rail stopper 17 approaches
the car guide rail 3). When the upper frictional surface 27a of the upper braking
shoe 27 contacts the car guide rail 3, the car guide rail 3 is gripped between the
upper braking shoe 27 and the bearing rail stopper 17.
[0038] If the central contacting surface 26a contacts the car guide rail 3 when the car
1 is ascending, the pivoting rail stopper 18 is pulled by the car guide rail 3 so
as to be pivoted downward. As the pivoting rail stopper 18 is pivoted downward while
placing the upper contacting curved surface 26b in contact with the car guide rail
3, the housing 13 is displaced in a direction in which the main shaft 24 moves away
from the car guide rail 3 (i.e., a direction in which the bearing rail stopper 17
approaches the car guide rail 3). When the lower frictional surface 28a of the lower
braking shoe 28 contacts the car guide rail 3, the car guide rail 3 is gripped between
the lower braking shoe 28 and the bearing rail stopper 17.
[0039] A displacement driving mechanism 29 that displaces the housing 13 relative to the
mounting frame 10 is disposed on the mounting frame 10 (Figures 3 and 4). The displacement
driving mechanism 29 has: a plurality of forcing springs (a forcing body) 30 that
force the housing 13 in a direction in which the pivoting rail stopper 18 contacts
the car guide rail 3; and a holding and releasing mechanism (a holding means) 31 that
can restrict the displacement of the housing 13 in opposition to the spring forces
from the forcing springs 30.
[0040] The forcing springs 30 are disposed between the sliding guides 13a and 13b and one
end portion of the mounting frame 10 (left end portion in Figure 2). Coil springs,
for example, can be used for the forcing springs 30. The sliding guides 13a and 13b
are passed through the respective forcing springs 30.
[0041] The holding and releasing mechanism 31 has: a gap distribution adjusting bolt 41
that is disposed on the adjusting bolt mount portion 16; a holding lever 32 that is
displaceable relative to the mounting frame 10, and that can engage with the gap distribution
adjusting bolt 41; a pushing pin 33 that is placed in contact with the holding lever
32; and an electromagnet 34 that displaces the pushing pin 33 to displace the holding
lever 32.
[0042] The pushing pin 33 and the electromagnet 34 are disposed on an opposite side of the
mounting frame 10 from the housing 13. The electromagnet 34 has: a fixed core (a first
core) 36 that is fixed to the mounting frame 10; an electromagnetic coil 37 that is
installed in the fixed core 36; and a movable core (a second core) 38 that is displaceable
relative to the fixed core 36.
[0043] The pushing pin 33 is fixed centrally on the movable core 38. The pushing pin 33
passes centrally through the fixed core 36. A plurality of adjusting nuts 39 are screwed
onto the pushing pin 33. Magnitude of a gap between the movable core 38 and the fixed
core 36 can be set to a predetermined value by adjusting positions of the adjusting
nuts 39.
[0044] The holding lever 32 is displaceable between a holding position that restricts displacement
of the housing 13 in a state in which the pivoting rail stopper 18 is separated from
the car guide rail 3 (Figure 3), and a releasing position that releases restriction
of the housing 13 (Figure 6). A lever mounting member is fixed to the fixed core 36.
One end portion of the holding lever 32 is pivotably mounted to the lever mounting
member by means of a pivoting support pin 40. A second end portion of the holding
lever 32 is placed in contact with the gap distribution adjusting bolt 41. The holding
lever 32 is displaced between the holding position and the releasing position by pivoting
around the pivoting support pin 40.
[0045] The gap distribution adjusting bolt 41 is screwed into the adjusting bolt mount portion
16 of the housing 13. The gap distribution adjusting bolt 41 is pressed horizontally
against the second end portion of the holding lever 32 by the forces from the respective
forcing springs 30. Gap dimensions between the car guide rail 3 and the pivoting rail
stopper 18 and between the car guide rail 3 and the bearing rail stopper 17 when the
holding lever 32 is in the holding position (i.e., when displacement of the housing
13 is being restricted) (Figures 2 and 3) can be adjusted by adjusting an amount of
thread engagement of the gap distribution adjusting bolt 41 in the adjusting bolt
mount portion 16.
[0046] The movable core 38 is attracted to the fixed core 36 when the electromagnet 34 is
excited. The pushing pin 33 is held by the attraction of the movable core 38 by the
fixed core 36 so as not to move relative to the fixed core 36. The holding lever 32
is held in the holding position by being placed in contact with the pushing pin 33
that is held against the fixed core 36. In other words, displacement of the holding
lever 32 from the holding position to the releasing position is restricted by excitation
of the electromagnet 34.
[0047] Holding force from the electromagnet 34 is set so as to overcome the spring forces
from the respective forcing springs 30 on the housing 42. Consequently, the bearing
rail stopper 17 and the pivoting rail stopper 18 are held away from the car guide
rail 3 by the excitation of the electromagnet 34 (Figures 2 and 3).
[0048] Restriction of the displacement of the holding lever 32 to the releasing position
is released by loss of the holding force due to stopping of the excitation of the
electromagnet 34. If the holding force from the electromagnet 34 is lost, the holding
lever 32 is pivoted by the respective forces from the forcing springs 30 while being
pushed onto the housing 13 by means of the gap distribution adjusting bolt 41, and
is displaced from the holding position to the releasing position. The housing 13 is
thereby displaced in a direction in which the pivoting rail stopper 18 contacts the
car guide rail 3.
[0049] Moreover, the gap distribution adjusting bolt 41 constitutes a housing position adjusting
means that can adjust the horizontal position of the housing 13 relative to the car
guide rail 3. A rail stopper interval adjusting means that can adjust a distance between
the pivoting center Cn of the pivoting rail stopper 18 and the bearing rail stopper
17 includes the shoulder bolts 19 and the positioning nuts 21.
[0050] Next, operation will be explained. Figure 5 is a structural diagram that shows a
state in which the central contacting surface 26a of the pivoting rail stopper 18
from Figure 2 contacts the car guide rail 3, and Figure 6 is a cross section that
has been taken along line VI - VI in Figure 5. Figure 7 is a structural diagram that
shows a state in which the lower frictional surface 28a of the pivoting rail stopper
18 from Figure 2 contacts the car guide rail 3, and Figure 8 is a cross section that
has been taken along line VIII - VIII in Figure 7.
[0051] During normal operation, as shown in Figures 2 and 3, the electromagnet 34 is excited
by control from the control board 4 so as to keep the movable core 38 attracted to
the fixed core 36. Here, the holding lever 32 is held in the holding position by coming
into contact with the pushing pin 33 (Figure 3), and pivoting to the releasing position
(pivoting in a clockwise direction in Figure 3) is restricted. Here also, both the
pivoting rail stopper 18 and the bearing rail stopper 17 are separated from the car
guide rail 3 by a predetermined gap by engagement of the gap distribution adjusting
bolt with the holding lever 32.
[0052] If an elevator abnormality is detected by the braking command portion 8, a braking
command is output from the braking command portion 8 to each of the emergency stopping
apparatuses 9. When the displacement driving mechanism 29 of each of the emergency
stopping apparatuses 9 receives the braking command, the passage of electric current
to the electromagnetic coil 37 is stopped, and the holding force from the electromagnet
34 is lost. The holding lever 32 is thereby pivoted from the holding position (Figure
3) to the releasing position (Figure 6) while being pushed by the housing 13 by the
forces from the respective forcing springs 30. Here, the pushing pin 33 is displaced
while being placed in contact with the holding lever 32. The movable core 38 is displaced
away from the fixed core 36. The displacement of the pushing pin 33 and the movable
core 38 is performed until the adjusting nuts 39 are placed in contact with the fixed
core 36.
[0053] Together with the displacement of the holding lever 32 to the releasing position,
the housing 13 is displaced in a direction in which the pivoting rail stopper 18 contacts
the car guide rail 3 (to the right in Figure 3) by the respective forces from the
forcing springs 30. Thus, the pivoting rail stopper 18 contacts the car guide rail
3, as shown in Figures 5 and 6.
[0054] If the pivoting rail stopper 18 contacts the car guide rail 3 when the car 1 is descending,
the pivoting rail stopper 18 is pulled by the car guide rail 3 so as to be pivoted
upward. Here, the lower contacting curved surface 26c contacts the car guide rail
3 due to the respective forces from the forcing springs 30 as the pivoting rail stopper
18 is pivoted. The housing 13 is thereby displaced in a direction in which the main
shaft 24 separates from the car guide rail 3, and the bearing rail stopper 17 is displaced
toward the car guide rail 3. Moreover, here, the gap distribution adjusting bolt 41
is separated from the holding lever 32 due to the displacement of the housing 13.
[0055] As the pivoting rail stopper 18 is subsequently pivoted further upward and the lower
braking shoe 28 reaches the car guide rail 3, the car guide rail 3 is gripped between
the lower braking shoe 28 and the bearing rail stopper 17, as shown in Figures 7 and
8. Here, the pressing elements 22 are compressed by the displacement of the bearing
rail stopper 17 that is pushed by the car guide rail 3, generating elastic resilience
that presses the bearing rail stopper 17 against the car guide rail 3. The lower frictional
surface 28a of the lower braking shoe 28 also contacts the car guide rail 3. The gripping
force on the car guide rail 3 is thereby ensured, imparting a braking force to the
car 1.
[0056] On the other hand, if the pivoting rail stopper 18 contacts the car guide rail 3
when the car 1 is ascending, the pivoting rail stopper 18 is pulled by the car guide
rail 3 so as to be pivoted downward. Here, the upper contacting curved surface 26b
contacts the car guide rail 3 due to the respective forces from the forcing springs
30 as the pivoting rail stopper 18 is pivoted. The housing 13 is thereby displaced
in a direction in which the main shaft 24 separates from the car guide rail 3, and
the bearing rail stopper 17 is displaced toward the car guide rail 3. Moreover, here,
the gap distribution adjusting bolt 41 is separated from the holding lever 32 due
to the displacement of the housing 13.
[0057] As the pivoting rail stopper 18 is subsequently pivoted further downward and the
upper braking shoe 27 reaches the car guide rail 3, the car guide rail 3 is gripped
between the upper braking shoe 27 and the bearing rail stopper 17. Here, the pressing
elements 22 are compressed by the bearing rail stopper 17 that is pushed by the car
guide rail 3, generating elastic resilience that presses the bearing rail stopper
17 against the car guide rail 3. The upper frictional surface 27a of the upper braking
shoe 27 also contacts the car guide rail 3. The gripping force on the car guide rail
3 is thereby ensured, imparting a braking force to the car 1.
[0058] In an elevator safety apparatus of this kind, because a bearing rail stopper 17 and
a pivoting rail stopper 18 are disposed on a housing 13 in which a distance to the
bearing rail stopper 17 is reduced by vertical pivoting, and a displacement driving
mechanism 29 that displaces the housing 13 in a direction in which the pivoting rail
stopper 18 contacts and separates from a car guide rail 3 is disposed on a mounting
frame 10, movement of a car 1 can be braked in either vertical direction by the action
of the common displacement driving mechanism 29. Thus, it is no longer necessary to
dispose separate driving mechanisms that brake movement of the car 1 in each vertical
direction, enabling reductions in the size of the emergency stopping apparatus 9 to
be achieved.
[0059] Because the displacement driving mechanism 29 has: forcing springs 30 that force
the housing 13 in a direction in which the pivoting rail stopper 18 contacts the car
guide rail 3; and a holding and releasing mechanism 31 that can restrict the displacement
of the housing 13 in opposition to the spring force from the forcing springs 30, the
housing 13 can be displaced by a simple configuration. Even if the holding force on
the housing 13 is lost due to failure of the holding and releasing mechanism 31, the
housing 13 can be displaced in a direction in which the pivoting rail stopper 18 contacts
the car guide rail 3 by the force from the forcing springs 30, enabling the braking
action of the car 1 to be performed more reliably.
[0060] Because the holding and releasing mechanism 31 has an electromagnet 34 that restricts
the displacement of the housing 13 by excitation, and performs release of the restriction
of the housing 13 by stopping excitation, a braking action can be performed in a short
amount of time.
[0061] Because the bearing rail stopper 17 and the pivoting rail stopper 18 are displaced
together with the housing 13, the construction for mounting the bearing rail stopper
17 and the pivoting rail stopper 18 onto the housing 13 can be simplified.
[0062] Because a gap distribution adjusting bolt 41 that can adjust a horizontal position
of the housing 13 relative to the car guide rail 3, and a rail stopper interval adjusting
means that can adjust a distance between a pivoting center Cn of the pivoting rail
stopper 18 and the bearing rail stopper 17 (shoulder bolts 19 and positioning nuts
21) are disposed on the housing 13, respective gap dimensions between the pivoting
rail stopper 18 and the car guide rail 3 and between the bearing rail stopper 17 and
the car guide rail 3 when the displacement of the housing 13 is being restricted by
the displacement driving mechanism 29 can be adjusted easily. Thus, adjustment of
the gap dimensions can be performed after mounting the emergency stopping apparatuses
9 to the car 1, enabling time spent on installation work to be reduced. Malfunctions
due to the mounting frame 10 being inclined, etc., can also be prevented.
[0063] Because either the upper contacting curved surface 26b or the lower contacting curved
surface 26c contacts the car guide rail 3 when the pivoting rail stopper 18 is pivoted
while contacting the car guide rail 3, and either the upper frictional surface 27a
or the lower frictional surface 28a contacts the car guide rail 3 when the car guide
rail 3 is gripped between the pivoting rail stopper 18 and the bearing rail stopper
17, contact of the pivoting rail stopper 18 with the car guide rail 3 during pivoting
of the pivoting rail stopper 18 can be made to be point contact or line contact, enabling
abrasion of the pivoting rail stopper 18 to be reduced. Extension of service life
can thereby be achieved, enabling the number of braking actions to be increased.
[0064] Because positions of an upper braking shoe 27 and a lower braking shoe 28 relative
to a pivoting rail stopper main body 26 are adjustable by adjustment of thicknesses
of spacers 45 and 46, if gripping force on the car guide rail 3 has been reduced by
abrasion, etc., of the upper braking shoe 27 and the lower braking shoe 28, for example,
the gripping force can be restored by adjusting the positions of the upper braking
shoe 27 and the lower braking shoe 28.
[0065] Because pressing elements 22 that press the bearing rail stopper 17 against the car
guide rail 3 are disposed between the bearing rail stopper 17 and the housing 13,
gripping force on the car guide rail 3 can be generated more reliably. Thus, braking
force can be applied to the car 1 more reliably.
[0066] Because presence or absence of an elevator abnormality is detected by a braking command
portion 8 based on respective information from a car speed detecting sensor 5, a door
opening and closing detecting sensor 6, and a main rope breakage detecting sensor
7, and braking action of the emergency stopping apparatuses 9 is performed on detection
of an abnormality by the braking command portion 8, a braking force can be applied
to the car 1 more reliably and in a shorter amount of time if an abnormality occurs
in the speed of the car 1, if the car 1 moves with the doorway of the car 1 open,
or if the main rope 2 breaks.
[0067] Moreover, in the above example, respective amounts of protrusion of the upper braking
shoe 27 and the lower braking shoe 28 from the pivoting rail stopper main body 26
are approximately identical, but the amount of protrusion of the upper braking shoe
27 may also be made less than the amount of protrusion of the lower braking shoe 28.
The braking force required to stop the ascending car 1 when balance between the car
1 and the counterweight is uneven may be smaller than the braking force required to
stop the descending car 1 if the main rope 2 breaks. Consequently, the braking force
required during the ascent of the car 2 can be made smaller than the braking force
required during the descent of the car 1 by making the amount of protrusion of the
upper braking shoe 27 less than the amount of protrusion of the lower braking shoe
28, enabling a braking force that corresponds to the direction of movement of the
car 1 to be applied to the car 1.
[0068] In the above example, the rail contacting surface of the pivoting rail stopper 18
is constituted by a flat surface 26a, and cylindrical surfaces 26b and 26c that are
centered around positions Pup and Pdn that are respectively offset upward and downward
from a pivoting center Cn, but the rail contacting surface is not limited to this
shape, and may also be shaped such that the main shaft 24 separates from the car guide
rail 3 continuously as the pivoting rail stopper 18 is pivoted while contacting the
car guide rail 3.
Embodiment 2
[0069] Figure 9 is a structural diagram that shows an emergency stopping apparatus 9 according
to Embodiment 2 of the present invention. Figure 10 is a cross section that has been
taken along line X - X in Figure 9, and Figure 11 is a cross section that has been
taken along line XI - XI in Figure 9. In the figures, a housing 13 has: a housing
main body 51; and an upper mounting guide portion 52 and a lower mounting guide portion
53 that are disposed on the housing main body 51, and that are arranged so as to be
spaced apart from each other in a vertical direction.
[0070] The upper mounting guide portion 52 and the lower mounting guide portion 53 project
toward a car guide rail 3 from the housing main body 51. The upper mounting guide
portion 52 has: a horizontal portion; and a bearing portion that extends downward
from an end portion of the horizontal portion at an opposite end from the car guide
rail 3. The lower mounting guide portion 53 has: a horizontal portion; and a bearing
portion that extends upward from an end portion of the horizontal portion at an opposite
end from the car guide rail 3.
[0071] A bearing rail stopper 17 is disposed between the upper mounting guide portion 52
and the lower mounting guide portion 53. The bearing rail stopper 17 is guided relative
to the housing 13 along the respective horizontal portions of the upper mounting guide
portion 52 and the lower mounting guide portion 53.
[0072] A plurality of (in this example, two) shoulder bolts 19 that are disposed horizontally
are fixed to the bearing rail stopper 17. Each of the shoulder bolts 19 extends toward
a back surface of the bearing rail stopper 17. Each of the shoulder bolts 19 passes
through a common backing plate (a restricting portion) 54 that is disposed between
the upper mounting guide portion 52 and the lower mounting guide portion 53.
[0073] A plurality of (in this example, two) pressing force adjusting bolts (adjusting elements)
55 through which the respective shoulder bolts 19 pass are screwed into the backing
plate 54. The pressing force adjusting bolts 55 are slidable horizontally relative
to the shoulder bolts 19.
[0074] Pressing elements 22 through which the shoulder bolts 19 are passed are respectively
disposed between the bearing rail stopper 17 and the respective pressing force adjusting
bolts 55 (i.e., on an opposite side of the bearing rail stopper 17 from the car guide
rail 3). The pressing elements 22 have a plurality of disk springs, for example. The
pressing elements 22 force the bearing rail stopper 17 away from the backing plate
54 using elastic resilience due to the disk springs being compressed.
[0075] The pressing force adjusting bolts 55 adjust the magnitude of the elastic resilience
of the pressing elements 22. Adjustment of the elastic resilience of the pressing
elements 22 is performed by the adjusting an amount of thread engagement of the pressing
force adjusting bolts 55 in the backing plate 54.
[0076] Each of the shoulder bolts 19 is passed through a washer 20, and is screwed into
a positioning nut 21. Displacement of the bearing rail stopper 17 away from the backing
plate 54 is restricted by the engagement of the washers 20 and the positioning nuts
21 with the backing plate 54. Adjustment of the position of the bearing rail stopper
17 relative to the backing plate 54 is performed by adjusting an amount of thread
engagement of the positioning nuts 21 on the shoulder bolts 19.
[0077] The bearing rail stopper 17 is displaceable relative to the housing 13 together with
each of the shoulder bolts 19, the washers 20, the positioning nuts 21, the pressing
elements 22, the backing plate 54, and the pressing force adjusting bolts 55. When
the bearing rail stopper 17 is displaced toward the backing plate 54, the pressing
elements 22 generates even larger elastic resilience in opposition to the displacement
of the bearing rail stopper 17.
[0078] A plurality of (in this example, two) forcing springs 68 are disposed so as to be
compressed between the bearing portion of the upper mounting guide portion 52 and
the bearing rail stopper 17 and between the bearing portion of the lower mounting
guide portion 53 and the bearing rail stopper 17, respectively. In other words, the
bearing rail stopper 17 is forced horizontally away from each of the bearing portions
of the upper mounting guide portion 52 and the lower mounting guide portion 53 by
the respective forcing springs 68.
[0079] A gap adjusting bolt 56 that passes horizontally through the backing plate 54 is
screwed into a portion of the backing plate 54 between each of the shoulder bolts
19. A locknut 57 for preventing displacement of the gap adjusting bolt 56 relative
to the backing plate 54 is screwed onto the gap adjusting bolt 56.
[0080] A lever passage aperture 58 is disposed on the housing main body 51. A holding lever
59 that is engaged with the gap adjusting bolt 56 is passed through the lever passage
aperture 58. The bearing rail stopper 17 is displaced relative to the housing 13 while
the gap adjusting bolt 56 is engaged with the holding lever 59. A distance between
the holding lever 59 and the backing plate 54 is adjusted by adjusting the amount
of thread engagement of the gap adjusting bolt 56 in the backing plate 54. The distance
between the bearing rail stopper 17 and the pivoting center Cn can thereby be adjusted.
[0081] An electromagnet 60 is disposed on a portion of the housing 13 on an opposite side
from the car guide rail 3. The electromagnet 60 has: a fixed core (a first core) 61
that is fixed to the housing 13; an electromagnetic coil 62 that is installed in the
fixed core 61; and a movable core (a second core) 63 that is displaceable relative
to the fixed core 61. The fixed core 61 and the movable core 63 can be attracted to
each other by passing an electric current to the electromagnetic coil 62 (i.e., excitation
of the electromagnet 60), and can be separated from each other in the direction of
displacement of the housing 13 by stopping the passage of electric current to the
electromagnetic coil 62.
[0082] A lever mounting member is fixed to the fixed core 61. One end portion of the holding
lever 59 is pivotably mounted to the lever mounting member by means of a pivoting
support pin 64. An end portion of the gap adjusting bolt 56 near the bearing rail
stopper 17 is pressed against a second end portion of the holding lever 59.
[0083] A pushing pin 65 that is disposed horizontally is fixed centrally on the movable
core 63. The pushing pin 65 passes centrally through the fixed core 61. An adjusting
nut 66 that restricts displacement of the fixed core 61 away from the movable core
63 is screwed onto the pushing pin 65. Magnitude of a gap between the movable core
63 and the fixed core 61 can be set to a predetermined value by adjusting a position
of the adjusting nut 66 relative to the pushing pin 65.
[0084] An intermediate portion of the holding lever 59 can be placed in contact with a tip
end portion of the pushing pin 65. A gap distribution adjusting bolt (a housing position
adjusting means) 67 that can be placed in contact with an intermediate portion of
the holding lever 59 is mounted to the mounting frame 10.
[0085] The respective intermediate portions of the holding lever 59 are placed in contact
with the pushing pin 65 and the gap distribution adjusting bolt 67 when the fixed
core 61 and the movable core 63 are attracted to each other. Both the bearing rail
stopper 17 and the pivoting rail stopper 18 are thereby held away from the car guide
rail 3. Specifically, when the fixed core 61 and the movable core 63 are attracted
to each other, displacement of the bearing rail stopper 17 toward the car guide rail
3 is restricted by the pushing pin 65 stopping the pivoting of the holding lever 59,
and displacement of the pivoting rail stopper 18 toward the car guide rail 3 is restricted
by the gap distribution adjusting bolt 67 stopping displacement of the housing 13.
[0086] A position at which displacement of the housing 13 is restricted by the gap distribution
adjusting bolt 67 can be adjusted by adjusting an amount of thread engagement of the
gap distribution adjusting bolt 67 in the mounting frame 10. In other words, gap dimensions
between the car guide rail 3 and the pivoting rail stopper 18 and between the car
guide rail 3 and the bearing rail stopper 17 (Figures 9 and 10) can be adjusted by
adjusting the amount of thread engagement of the gap distribution adjusting bolt 67
in the mounting frame 10.
[0087] The housing 13 is displaced to the right in Figure 10 by spring forces from each
of the forcing springs 30 and 68 when the fixed core 61 and the movable core 63 are
separated from each other, pivoting the holding lever 59 counterclockwise in Figure
10. In other words, the housing 13 and the holding lever 59 are displaced when the
fixed core 61 and the movable core 63 are separated from each other such that the
bearing rail stopper 17 and the pivoting rail stopper 18 are displaced toward each
other. Thus, the bearing rail stopper 17 and the pivoting rail stopper 18 each contact
the car guide rail 3.
[0088] A plurality of (in this example, two) center of gravity adjusting apertures 69 are
disposed on the pivoting rail stopper main body 26. The center of gravity of the pivoting
rail stopper 18 is thereby aligned with the pivoting center Cn. In this example, the
center Pup of the upper contacting curved surface 26b is positioned near the Y-axis
in a first quadrant of X - Y coordinates that are centered around the pivoting center
Cn, and the center Pdn of the lower contacting curved surface 26c is positioned near
the Y-axis in a fourth quadrant. In addition, a bearing 25 between the pivoting rail
stopper 18 and the main shaft 24 is a rolling bearing.
[0089] Moreover, a displacement driving mechanism 29 includes the respective forcing springs
30 and a holding and releasing mechanism (a holding means). The holding and releasing
mechanism (the holding means) includes the holding lever 59, the electromagnet 60,
the pushing pin 65, and the gap distribution adjusting bolt 67. In addition, a rail
stopper interval adjusting means that adjusts a distance between the pivoting center
Cn of the pivoting rail stopper 18 and the bearing rail stopper 17 includes the backing
plate 54, the gap adjusting bolt 56, the locknut 57, and the respective forcing springs
68. The rest of the configuration is similar to that of Embodiment 1.
[0090] Next, operation will be explained. Figure 12 is a structural diagram that shows a
state in which the central contacting surface 26a of the pivoting rail stopper 18
from Figure 9 contacts the car guide rail 3, and Figure 13 is a cross section that
has been taken along line XIII - XIII in Figure 12. Figure 14 is a structural diagram
that shows a state in which the lower frictional surface 28a of the pivoting rail
stopper 18 from Figure 9 contacts the car guide rail 3, and Figure 15 is a cross section
that has been taken along line XV - XV in Figure 14.
[0091] During normal operation, as shown in Figures 9 and 10, the electromagnet 60 is excited
by control from the control board 4 such that the fixed core 61 and the movable core
63 are attracted to each other. Here, displacement of the bearing rail stopper 17
toward the car guide rail 3 (displacement to the left in Figure 10) is restricted
by the holding lever 59, and displacement of the pivoting rail stopper 18 toward the
car guide rail 3 (displacement to the right in Figure 10) is restricted by the gap
distribution adjusting bolt 67. Both the pivoting rail stopper 18 and the bearing
rail stopper 17 are thereby separated from the car guide rail 3 by a predetermined
gap.
[0092] If the displacement driving mechanism 29 of each of the emergency stopping apparatuses
9 receives a braking command, the passage of electric current to the electromagnetic
coil 62 is stopped, and the holding force from the electromagnet 60 is lost. When
the holding force from the electromagnet 60 is lost, the fixed core 61 and the movable
core 63 are displaced away from each other by the forces from the forcing springs
30 and 68. The housing 13 is thereby displaced together with the fixed core 61, displacing
the pivoting rail stopper 18 toward the car guide rail 3 (to the right in Figure 10).
Here, the holding lever 59 is also pivoted counterclockwise in Figure 10, displacing
the bearing rail stopper 17 toward the car guide rail 3.
[0093] As shown in Figures 12 and 13, the bearing rail stopper 17 and the pivoting rail
stopper 18 subsequently contact the car guide rail 3. The bearing rail stopper 17
is subsequently pressed onto the car guide rail 3 by the forces from the respective
forcing springs 68, and the pivoting rail stopper 18 is pressed onto the car guide
rail 3 by the forces from the respective forcing springs 30. Moreover, the forces
from the forcing springs 30 and 68 are set such that these pressing forces balance
each other.
[0094] Next, if the car 1 is descending, the pivoting rail stopper 18 is pulled by the car
guide rail 3 so as to be pivoted upward. Here, the lower contacting curved surface
26c of the pivoting rail stopper 18 is pivoted while contacting the car guide rail
3 due to the respective forces from the forcing springs 30. The housing 13 is thereby
displaced in a direction in which the main shaft 24 separates from the car guide rail
3 (to the left in Figure 12).
[0095] As the pivoting rail stopper 18 is subsequently pivoted further, and the housing
13 is displaced in a direction in which the main shaft 24 separates from the car guide
rail 3, each of the bearing portions of the upper mounting guide portion 52 and the
lower mounting guide portion 53 engages with the backing plate 54, further compressing
the pressing elements 22.
[0096] As the lower braking shoe 28 reaches the car guide rail 3, the car guide rail 3 is
gripped between the lower braking shoe 28 and the bearing rail stopper 17 (Figures
14 and 15). Here, the pressing elements 22 are compressed by the displacement of the
bearing rail stopper 17 that is pushed by the car guide rail 3, generating elastic
resilience that presses the bearing rail stopper 17 against the car guide rail 3.
The lower frictional surface 28a of the lower braking shoe 28 also contacts the car
guide rail 3. The gripping force on the car guide rail 3 is thereby ensured, imparting
a braking force to the car 1.
[0097] On the other hand, if the pivoting rail stopper 18 contacts the car guide rail 3
when the car 1 is ascending, the pivoting rail stopper 18 is pulled by the car guide
rail 3 so as to be pivoted downward. Here, the upper contacting curved surface 26b
of the pivoting rail stopper 18 is pivoted while contacting the car guide rail 3 due
to the respective forces from the forcing springs 30. The housing 13 is thereby displaced
in a direction in which the main shaft 24 separates from the car guide rail 3.
[0098] As the pivoting rail stopper 18 is subsequently pivoted further, and the housing
13 is displaced in a direction in which the main shaft 24 separates from the car guide
rail 3, each of the bearing portions of the upper mounting guide portion 52 and the
lower mounting guide portion 53 engages with the backing plate 54, further compressing
the pressing elements 22.
[0099] As the upper braking shoe 27 subsequently reaches the car guide rail 3, the car guide
rail 3 is gripped between the upper braking shoe 27 and the bearing rail stopper 17.
Here, the pressing elements 22 are compressed by the displacement of the bearing rail
stopper 17 that is pushed by the car guide rail 3, generating elastic resilience that
presses the bearing rail stopper 17 against the car guide rail 3. The upper frictional
surface 27a of the upper braking shoe 27 also contacts the car guide rail 3. The gripping
force on the car guide rail 3 is thereby ensured, imparting a braking force to the
car 1.
[0100] In an elevator safety apparatus of this kind, because a bearing rail stopper 17 is
displaced in a reverse direction to a direction in which a housing 13 is displaced,
distances between a car guide rail 3 and a bearing rail stopper 17 and between the
car guide rail 3 and a pivoting rail stopper 18 can be widened during normal operation,
further enabling prevention of malfunction as a result of the car 1 inclining.
[0101] Because adjustment of elastic resilience of pressing elements 22 is performed by
adjusting an amount of thread engagement of pressing force adjusting bolts 55 in a
backing plate 54, pressing force from the bearing rail stopper 17 onto the car guide
rail 3 can be adjusted easily.
[0102] Because a center of gravity of the pivoting rail stopper 18 is aligned with a pivoting
center Cn of the pivoting rail stopper 18, pivoting of the pivoting rail stopper 18
can be prevented even if rocking, etc., of the car 1 arises, for example.
[0103] Moreover, in the above example, the center of gravity of the pivoting rail stopper
18 is aligned with the pivoting center Cn of the pivoting rail stopper 18, but the
center of gravity of the pivoting rail stopper 18 may also be positioned below the
pivoting center Cn on the Y-axis. Pivoting of the pivoting rail stopper 18 that occurs
due to rocking, etc., of the car 1 can also be prevented in this manner.
[0104] In the above example, the pressing force adjusting bolts 55 are screwed into the
backing plate 54, but may also be screwed into a back surface of the bearing rail
stopper 17.
In addition, sensors are not limited to the car speed detecting sensor 5, the door
opening and closing detecting sensor 6, and the main rope breakage detecting sensor
7.
1. An elevator safety apparatus
characterized in comprising:
a housing that is supported by a car that is guided by a guide rail, and that is displaceable
horizontally relative to the car;
a bearing rail stopper that is disposed on the housing;
a pivoting rail stopper that is disposed on the housing such that the guide rail is
disposed between the pivoting rail stopper and the bearing rail stopper, and that
can be pivoted vertically such that a distance to the bearing rail stopper is reduced
by the vertical pivoting; and
a displacement driving mechanism that displaces the housing relative to the car in
a direction in which the pivoting rail stopper separates from and contacts with the
guide rail,
the guide rail being gripped between the pivoting rail stopper and the bearing rail
stopper by the pivoting rail stopper being pivoted in a direction that corresponds
to a direction of movement of the car while contacting the guide rail.
2. An elevator safety apparatus according to Claim 1, characterized in that the displacement driving mechanism comprises: a forcing body that forces the housing
in a direction in which the pivoting rail stopper contacts the guide rail; and a holding
means that can restrict displacement of the housing in opposition to force from the
forcing body.
3. An elevator safety apparatus according to Claim 2, characterized in that the holding means comprises an electromagnet that restricts displacement of the housing
by excitation, and that performs release of the restriction by stopping the excitation.
4. An elevator safety apparatus according to Claim 1, characterized in that the bearing rail stopper and the pivoting rail stopper are displaced together with
the housing.
5. An elevator safety apparatus according to Claim 1, characterized in that the bearing rail stopper is displaceable relative to the housing, the pivoting rail
stopper can be displaced together with the housing, and the displacement driving mechanism
displaces the bearing rail stopper in a reverse direction to a direction in which
the housing is displaced.
6. An elevator safety apparatus according to Claim 1, characterized in that the displacement driving mechanism comprises: a housing position adjusting means
that can adjust a position of the housing relative to the guide rail; and a rail stopper
interval adjusting means that can adjust a distance between a pivoting center of the
pivoting rail stopper and the bearing rail stopper.
7. An elevator safety apparatus according to Claim 1,
characterized in that:
a rail contacting surface that includes a curved surface portion, and flat surface
portions that are adjacent to an upper end and a lower end of the rail contacting
surface are disposed on the pivoting rail stopper; and
the curved surface portion contacts the guide rail when the pivoting rail stopper
is pivoted while contacting the guide rail, and the flat surface portion contacts
the guide rail when the guide rail is gripped between the pivoting rail stopper and
the bearing rail stopper.
8. An elevator safety apparatus according to Claim 1,
characterized in that:
the pivoting rail stopper comprises a pivoting rail stopper main body; and a pair
of braking shoes that are disposed on the pivoting rail stopper main body, and that
contact the guide rail when the guide rail is gripped between the pivoting rail stopper
and the bearing rail stopper; and
a position of each of the braking shoes relative to the pivoting rail stopper main
body is adjustable.
9. An elevator safety apparatus according to Claim 1, characterized in that a center of gravity of the pivoting rail stopper is aligned with a pivoting center
of the pivoting rail stopper.
10. An elevator safety apparatus according to Claim 1, characterized in further comprising a pressing element that presses the bearing rail stopper against
the guide rail when the guide rail is gripped between the bearing rail stopper and
the pivoting rail stopper.
11. An elevator safety apparatus according to Claim 10, characterized in that the pressing element and an adjusting element are disposed so as to overlap with
each other between the bearing rail stopper and a restricting portion by which displacement
away from the bearing rail stopper is restricted; and
the adjusting element is a pressing force adjusting bolt that adjusts a pressing force
from the pressing element by adjusting an amount of thread engagement relative to
at least one of the bearing rail stopper and the restricting portion.
12. An elevator safety apparatus according to Claim 1, characterized in further comprising a determining portion that detects presence or absence of an elevator
abnormality and outputs a braking command based on at least one of a car speed detecting
portion that detects speed of the car, a door opening and closing detecting portion
that detects whether a doorway of the car is open or closed, and a main rope breakage
detecting portion that detects presence or absence of a breakage of a main rope that
suspends the car, and
the displacement driving mechanism displaces the housing in a direction in which the
pivoting rail stopper contacts the guide rail due to receiving the braking command.