FIELD OF THE INVENTION
[0001] This invention relates to a latch holding apparatus of a handle for opening and closing
a door, in which the handle is placed in a locked state by holding a latch in a locked
position. More particularly, the invention relates to a latch holding apparatus used
in a double-leafed hinged door attached to the rear or side of, e.g., a van-type vehicle,
and adapted in such a manner that when a handle to be locked is placed in a locked
state or unlocked state, the latch can be held reliably in a locked position or unlocked
position, respectively.
RELATED BACKGROUND ART
[0002] Conventionally, a latch apparatus for locking a handle which opens and closes a door
is used in a double-leafed hinged door of a van-type vehicle or sea-borne container.
Prior art disclosed in US Serial No. 19867 filed on March 16, 1970 will now be described
with reference to Figs. 15 and 16 as an example of such a latch apparatus.
[0003] First, in Fig. 15, numeral 1 denotes a double-leafed hinged door attached to an opening
at the rear or side of a van-type vehicle V or sea-borne container. The double-leafed
hinged door 1 is mounted by hinges 2 on a side column 3 of the opening. Numeral 4
denotes a locking rod constituting a lock device. The rod 4 has cams 5 at its upper
and lower ends and is mounted on the main body of the door 1 so as to be capable of
turning. A handle 6 for turning the locking rod 4 about its axis is provided on the
rod 4 as a integral part thereof. Numeral 7 denotes a cam keeper provided on upper
and lower frame members of the opening. The upper and lower cams 5, 5 of the locking
rod 4 turn when the door 1 is opened, whereupon the cams engage with their respective
cam keepers 7. Numeral 8 denotes a latch apparatus for retaining the handle 6, which
turns in unison with the locking rod 4, in a horizontal attitude, and for locking
the handle 6 at the time of a closing operation.
[0004] Fig. 16, which is a perspective view of the portion indicated by the arrow XXIV in
Fig. 15, shows the details of the latch apparatus and handle 6. In this conventional
latch apparatus, the handle 6 is engaged with and supported by a bracket 9 fixedly
secured to the double-leafed hinged door. A door lock latch 10 capable of being turned
up and down has a simple structure in which the latch 10 is engaged with the handle
6 from above to prevent the handle 6 from separating from the bracket 9. Numeral 11
denotes concentric holes provided in the bracket 9 and latch 10. Locking is achieved
by inserting the shank of a padlock 12 through the holes 11. The handle cannot be
turned unless the padlock 12 is opened.
[0005] The conventional latch apparatus 8 thus constructed involves a troublesome opening
and closing operation since the latch is held by the padlock 12. Specifically, in
terms of the operation performed at unlocking,
(1) first the padlock 12 is unlocked by means of a key;
(2) the shank of the padlock 12 is withdrawn from the concentric holes 11 of the bracket
9 and door lock latch 10;
(3) the door lock latch 10 is turned clockwise about a pivot shaft 13; and
(4) the handle 6 is turned upwardly slightly by hand and pulled forward from the position
indicated by the two-dot chain lines to turn the locking rod 4, thereby opening the
door.
[0006] Though the double-leafed hinged door 1 is opened by the series of operations (1)
through (4) mentioned above, these operations are difficult to perform when the user
is carrying a load, unless the load is first set on the ground. In particular, operations
(2) and (4) cannot be carried out with only one hand, and even greater difficulties
are encountered in case of rainy weather.
[0007] A biasing apparatus is known as a latch holding apparatus for holding the latch reliably
in its locked position or unlocked position. For example, in the case of a lock device
of a handle for an apparatus which locks a van-type vehicle, the biasing apparatus
uses a spring which applies a force in mutually opposing directions in such a manner
that the locked position and unlocked position of the locking latch member can be
reliably maintained.
[0008] As shown in Fig. 17, numeral 71 denotes a biased body moved between the position
of a pin a and the position of a pin b. The biased body is a latch member for locking
the handle of a van-type vehicle, by way of example. The biased body 71 turns about
a pivot shaft 72 to be changed over between the position of pin a and the position
of pin b. Numeral 73 denotes a coil spring having one end engaged with a pin 74 provided
on an end of the biased body 71, and another end engaged with a fixed pin 75 separate
from the biased body 71.
[0009] A force is applied in the direction of arrow A in order to change over the biased
body 71 from the position of pin a in Fig. 17(a) to the position of pin b in Fig.
17(b). When this is done, the coil spring 73a stretches to a point beyond a straight
line X-X′ passing through the pivot shaft 72, namely a point beyond a neutral position.
Therefore, the biased body is turned against the spring force, though when the straight
line X-X′ is surpassed, the biased body is turned automatically to the position b,
where it comes to rest. At the position of pin b, the coil spring 73a causes the spring
force to act upon the biased body 71 between the pins 74 and 75, thereby producing
a moment in a direction where the force attempts to turn the biased body further.
As a result, the biased body 71 is held at the position b.
[0010] Figs. 18(a), (b) shows another example of the biasing device. Here a leaf spring
73b is used as the spring which applies the spring force to the biased body 71. If
the biased body 71 is pushed against a maximum repulsive force, produced when it passes
over a central projection 76b of the leaf spring 73b, at such time that the biased
body 71 is moved from the a position to the b position, the biased body 71 will turn
automatically and be held at the b position.
[0011] Figs. 19(a) (b) also show another example of the biasing device. Here the arrangement
used is one in which one end of a torsion coil spring 73c is engaged with a pin 77
provided on the lower portion of the biased body 71. Operation is the same as in the
foregoing two examples, with the biased body being held at the a and b positions by
the coil spring 73c.
[0012] Figs. 20(a) (b) show yet another example of the biasing device. Here a spring seating
member 80 is attached to the lower portion of the biased body 71 via a pin 78, and
a spring seating member 81 is attached via a pin 79 to a fixed position separate from
the biased body 71. A coil spring 73d is attached between the two spring seating members
80, 81. Accordingly, when the biased body is in line with the neutral line X-X′, the
coil spring 73 is compressed to the maximum extent, whereby the maximum spring force
is generated. When this neutral position is exceeded, the biased body is turned automatically
toward the b position or the a position, where it comes to rest.
[0013] Among the foregoing well-known biasing devices, spring lengths ℓ₁, ℓ₂ in the examples
of Figs. 17 and 20 are of considerable size in a case where a prescribed biasing force
is required. In the example of Fig. 18, the width ℓ₃ of the leaf spring 73b is large.
In the example of Fig. 19, the length and width of the coil spring 73c are of considerable
size. For these reasons, problems arise when it is attempted to make the well-known
biasing devices smaller in size and more compact.
DISCLOSURE OF THE INVENTION
[0014] The present invention has been devised in order to solve the foregoing problems and
its object is to provide a latch holding apparatus of a handle for opening and closing
a door used very frequently, in which a latch member can be held in its locked and
unlocked positions reliably and the handle can be locked and unlocked by a single
touch.
[0015] Another object of the present invention is to provide a safely operable latch holding
apparatus of a handle for opening and closing a door, in which the apparatus can be
attached at a hidden position of a latch device or the like for locking the handle,
and in which the positioning of a held latch can be performed in reliable fashion.
[0016] In accordance with the present invention, there is provided a latch holding apparatus
of a handle for opening and closing a door, in which a latch pivotally secured to
a base fixed to a door main body is held in a locked position, whereby the handle
is placed in a locked state, the apparatus comprising a pair of handle grips in each
of which a recess is formed for insertion of the handle, a pivot shaft for turnably
supporting the latch on the handle grips, and holding means for holding the latch
in the locked position when the handle is inserted into the handle grips, and turning
the latch and holding it in an unlocked position when the handle is separated from
the handle grips.
ADVANTAGEOUS EFFECTS OF THE INVENTION IN THE CONTEXT OF THE BACKGROUND ART
[0017] Accordingly, the latch holding apparatus of a handle for opening and closing a door
in the present invention is such that the latch member is pivotally secured to the
base and is capable of being held in its open and closed positions by a simply constructed
holding device. The invention therefore is very effective when utilized in a collection
and delivery vehicle for parcels and the like, in which a door is opened and closed
very frequently.
[0018] In particular, the holding apparatus is such that when the handle is manipulated
in a state where the latch member is in the open position, the latch can be held in
the open position automatically. Conversely, the latch member can readily be turned
to the open position by hand, whereupon it can be held in this position immediately.
Therefore, the apparatus is convenient in that it can be operated very easily even
by an operator busily involved in collection and delivery.
[0019] Other features and advantages of the present invention will be apparent from the
following description taken in conjunction with the accompanying drawings, in which
like reference characters designate the same or similar parts throughout the figures
thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020]
Figs. 1 through 4 show a first embodiment of the present invention, in which:
Fig. 1 is a side sectional view;
Fig. 2 is a perspective view of a latch member;
Fig. 3 is a sectional view of a holding device; and
Fig. 4 is a perspective view of a base;
Figs. 5 through 7 show a second embodiment of the present invention, in which:
Fig. 5 is a side sectional view;
Fig. 6 is an enlarged sectional view illustrating the state of the holding device
holding a latch in a locked position; and
Fig. 7 is an enlarged sectional view illustrating the state of the holding device
turning the latch and holding it in an unlocked position;
Figs. 8 and 9 show a third embodiment of the present invention, in which:
Fig. 8 is a side sectional view, and
Fig. 9 is a perspective view of a base;
Figs. 10 through 12 show a fourth embodiment of the present invention, in which:
Fig. 10 is a sectional view illustrating the state of a biasing device for biasing
a latch pivotally secured to a base;
Fig. 11 is a front view showing a pin seat constituting the biasing device; and
Fig. 12 is an explanatory view showing the action of the biasing device;
Fig. 13 is a sectional view showing another biasing device;
Fig. 14 is a sectional view showing a well-known biasing device;
Fig. 15 is a front view of a well-known double-leafed hinged door;
Fig. 16 is a diagram showing the details of a portion indicated at arrow XVI in Fig.
15; and
Figs. 17 through 20 are explanatory views illustrating biasing devices using well-known
springs.
BEST MODE FOR CARRYING OUT THE INVENTION
[0021] Embodiments of the present invention will now be described in detail with reference
to the drawings.
[0022] The basic structural elements of an apparatus according to a first embodiment of
the invention illustrated by Figs. 1 through 4 are four members, namely a base 20,
a latch member 30 which operates in cooperation with the base 20, and a holding device
40 for holding the latch member 30 in a closed position.
[0023] Fig. 3 is a sectional view showing a principal portion of the latch holding apparatus.
As shown in Fig. 1, the base 20 is fixedly secured to, e.g., the main body of a double-leafed
hinged door 1, by a bolt 22 inserted from the inner side of the main body of the door
1 and passed through the handle 6 at a prescribed position. Tightening is accomplished
by a nut 23. To this end, the base 20 is rectangular in shape and is provided with
a bolt-insertion hole 21 at each of the four corners of the rectangle, as shown in
Fig. 4.
[0024] A pair of left and right handle grips 24 are provided on the top side of the base
20. The handle grips 24 project upwardly by a distance t from the base 20 in such
a manner that the handle 6 can be inserted from above. A recess 24a for inserting
the handle is formed between the handle grips 24 and the base 20.
[0025] Fig. 2 is a perspective view of the latch member. The latch member 30 has a transverse
dimension that allows it to fit between the pair of left and right handle grips 24,
and is attached to the handle grips 24 by a pivot shaft 25. The upper portion of the
latch member protrudes upward from the handle grips 24 and has an inwardly directed
projection 31 forming a C-shaped recess 32. The handle grips 24 are provided with
respective holes 25a for attaching the pivot shaft 25, which is attached to the latch
member 30 substantially at the central portion thereof. The latch member 30 turns
up and down with the pivot shaft 25 serving as the center of turning motion. The lower
portion of the latch member 30 has the shape of a downwardly directed wedge. The holding
device 40 is attached to the latch member 30 at a portion thereof below the position
of the pivot shaft 25.
[0026] The construction of the latch holding device 40 will now be described in greater
detail. A hole 42 for mounting the holding device is provided in the lower portion
of the latch member 30 below the hole for the pivot shaft 25 serving as the center
of turning motion. Fitted into the hole 42 are pins 41 having a hemispherical shape
and constituting the holding device 40. When the latch member 30 is turned, the pins
41 are urged outwardly by a compression spring 43 in such a manner that the heads
of the pins are fitted alternately into two recesses 41a, 41b provided in each of
the handle grips 24 on the inner side thereof below the hole 25a. More specifically,
the two recesses 41a, 41b are spaced apart by about 20° and have the same radii with
the hole 25a as center. The locking device holds the latch member 30 in the locked
position (the position of the solid lines in Fig. 1) or in the unlocked position (the
position of the phantom lines in Fig. 1) after the latch is turned.
[0027] Accordingly, in order to turn the latch member 30, place it in the unlocked position
and unlock the handle 6, the side of the latch member 30 below the pivot shaft 25
is pressed or the head portion of the latch member 30 is pulled forward. In a case
where the handle 6 is to be locked, the handle 6 is swung down from above the latch,
whereupon the handle 6 fits between the latch member 30 and the base 20 and strikes
a bottom 32a of the C-shaped recess 32 in the latch member 30. As a result, the latch
member 30 turns in the locking direction (clockwise in Fig. 1). At this time the holding
device 40 also turns so that the pins 41 fit into the recesses 41a, which is on the
side of the locking position of the latch member 30. The holding device holds the
latch member 30 is this position.
[0028] A second embodiment of the invention will now be described with reference to Figs.
5 through 7.
[0029] As in the first embodiment described above, the latch holding apparatus of this embodiment
includes the base 20 and the latch member 30, which cooperates with the base 20, as
basic structural elements. The holding device for holding the latch member 30 in its
locked position has a construction described below.
[0030] Fig. 6 is an enlarged sectional view showing the state of the locking device holding
the latch member 30 in the locked position. The holding device comprises two projections
33a, 33b provided on the latch at positions below the pivot shaft 25 on the inner
side of the latch, and a leaf spring 44 provided astride a recess 46 formed in the
base. The two projections 33a, 33b are situated on the latch member 30 within a radius
R at a position below the pivot shaft 25. The leaf spring 44 is secured to the base
20 by fixtures 45 and is formed to have two projections 44a, 44b corresponding to
the projections 33a, 33b. The arrangement is such that when the latch member 30 turns,
the leaf spring 44 is capable of flexing without effort.
[0031] The operation of the latch holding device of a handle for opening and closing a door
will now be described. When the locked position is maintained, the projection 33a
on the side of the latch member 30 fits into the recess 44c of the leaf spring 44,
as shown in Fig. 6, and this position is maintained.
[0032] Next, in order to establish the unlocked position, the lower portion of the latch
member 30 is urged in the direction of arrow a in Fig. 5. As a result, the projection
33b on the lower side of the latch member 30 is turned upward, slides over the projection
44b on the lower side of the leaf spring 44 and fits into the recess 44c. Thus the
latch member 30 is held in its unlocked position (the position indicated by the two-dot
chain lines in Fig. 5).
[0033] A third embodiment of the present invention will now be described with reference
to Figs. 8 and 9.
[0034] In this embodiment, magnets 46a and 46b are imbedded in upper and lower portions
of the base 20. The magnet 46a corresponds to the inwardly directed projection 31
provided on the upper portion of the latch member 30, which is made of metal. The
magnet 46b is provided to correspond to the wedge-shaped portion at the lower part
of the latch member 30. It goes without saying that the magnets 46a, 46b may be provided
on the latch member 30 rather than the base 20.
[0035] In the operation of the latch holding device, the inwardly directed projection 31
is magnetically attracted to the magnet 46a with the latch member 30 in the locked
position, which is indicated by the solid line in Fig. 8. This position is maintained
as a result of the attraction between the projection 31 and the magnet 46a.
[0036] When the lower portion of the latch member 30 is pushed against the attractive force
of the magnet 46a, the lower portion of the latch member 30 is attracted to the magnet
46b and this position is maintained (the position indicated by the two-dot chain line
in Fig. 8).
[0037] A fourth embodiment of the present invention will be described with reference to
Figs. 10 through 13.
[0038] As in the first embodiment described above, the latch holding apparatus of this embodiment
includes the base 20 and the latch member 30, which cooperates with the base 20, as
basic structural elements. Here the holding device for holding the latch member 30
in its locked position employs a biasing device using a spring applying a biasing
force in mutually opposing directions in such a manner that the latch member for locking
can be held reliably in its locked and unlocked positions.
[0039] Fig. 10 is a sectional view showing a biasing device according to this embodiment.
A biased body 53 urged in a positioning direction is a latch member capable of being
turned between pins a and b about a pivot shaft 54. Numeral 55 denotes a pin having
a hemispherical head for supporting the upper portion of the biasing device 52. The
pin 55 is fixedly secured to a portion of the biased body 53 below the pivot shaft
54. Numeral 56 denotes a pin having a hemispherical head for supporting the lower
portion of the biasing device 52. The pin 56 is attached to a fixed base 57.
[0040] Fig. 11 is a sectional view illustrating a pin seat constituting the biasing device.
The pin seat 58 has a bowl-shaped recess 59 provided in one end thereof in the axial
direction. This end of each pin seat is formed to have a spring seating flange 60
surrounding the recess 59. The pin seats 58 are installed end to end with their recessed
portions facing away from each other, and heads 55a, 56a of the pins 55, 56 are fitted
into the recesses 59 of the pin seats. Numeral 61 denotes a spring loaded between
the spring seating flanges 60 of the upper and lower pin seats 58.
[0041] As shown in Fig. 12, the biasing device 52 is such that when the center of the upper
pin 55 is at a position O₁ to the left of a straight line X-X′ connecting the center
of the head portion of pin 56 and the center O of the pivot shaft 54 serving as the
rotational center of the biased body 53, the biased body 53 is biased in the locking
direction or unlocking direction. When the center of the head portion of pin 55 is
at a position O₂ to the right of the straight line X-X′, the biased body 53 is biased
conversely in the locking direction or unlocking direction.
[0042] The biasing device 52 is characterized in that it operates in an effective manner
even if a distance E between the center O₃ of the pin 56 and the rotational center
(pivot shaft) O of the biasing body 53 is very small.
[0043] In the fourth embodiment constructed as set forth above, the biased body 53 is restrained
and positioned by the pin a in the state shown in Fig. 10. However, when the biased
body 53 is turned in the direction of the arrow, it rotates about the pivot shaft
54. As a result, the pin 55 turns at the same time and so does the pin seat 58 while
the bowl-shaped recess 59 is in contact with the tip of the pin. The turning motion
takes place against the spring force of the coil spring 61 and becomes maximum when
the line X-X′ connecting the pivot shaft 54 and pin 56 is surpassed. When this line
is surpassed, the biased body 53 turns under its own force and is positioned at pin
b on the opposite side.
[0044] In comparison with the well-known biasing devices having the springs shown in Figs.
17 through 20 described earlier, the biasing device 54 of the fourth embodiment can
be easily mounted in the small mounting space between the base 57 attached to the
door 1 of the van-type vehicle and the latch member, which is the biased body 53,
and the biasing device 54 is capable of performing fully the function of a latch holding
device.
[0045] Fig. 13 shows another embodiment. Here the pin 55 with the hemispherical head and
the pin seat 58 are integrated into a unitary body. More specifically, upper and lower
pin seats 58′ have an identical construction, and a pin 55′ and spring seating flange
60′ are formed into a unitary body.
[0046] Since the pin 55′ is integrated with the pin seat 58′, bowl-shape recesses 59′ are
provided on the side of the biased body 53 which is positioned and on the side of
the base 57. Numeral 68 denotes a coil spring installed between the opposing upper
and lower spring seating flanges 60′, 60′.
[0047] Fig. 14 shows a well-known biasing device corresponding to the principle of Fig.
20. This will be compared with the fourth embodiment of the invention shown in Fig.
10.
[0048] Let the following hold:
A = A′ (distance between the pivot shaft of the biased body and the center of the
pin tip)
B = B′ (length of spring)
We will then have
C < C′, D > D′, E < E′
where C, C′: distance between centers of upper and lower pin tips
D, D′: deviation of pin tip from neutral position
E, E′: overall length of device
[0049] Thus, in accordance with the apparatus of the fourth embodiment, it is possible to
achieve the relation C < B, whereas C′ > B′ holds in the case of the well-known apparatus
of Fig. 14. In other words, even if the length B of spring 61 is made sufficiently
large, the overall biasing device can be made compact. As a result, the apparatus
can be installed easily even in a small space.
1. A latch holding apparatus of a handle for opening and closing a door, in which
a latch pivotally secured to a base fixed to a door main body is held in a locked
position, whereby the handle is placed in a locked state, comprising:
a pair of handle grips in each of which a recess is formed for insertion of the handle;
a pivot shaft for turnably supporting the latch on said handle grips; and
holding means for holding the latch in the locked position when the handle is inserted
into said handle grips, and turning the latch and holding it in an unlocked position
when the handle is separated from said handle grips.
2. The apparatus according to claim 1, wherein said holding means comprises:
an urging device comprising a compression spring and pins on both sides of said compression
spring, said urging device being fitting into a hole provided in the latch at a position
below said pivot shaft and lying parallel to said pivot shaft; and
recesses provided in said handle grips so as to be capable of being engaged and disegaged
by the pins on both sides of said urging device, said recesses corresponding to respective
ones of a locked position and unlocked position of the latch.
3. The apparatus according to claim 1, wherein said holding means comprises:
two projections provided on said latch at positions on an inner side thereof below
said pivot shaft, said two projections being provided on identical radii having said
pivot shaft as the center; and
a leaf spring provided astride a recess provided in the base and corresponding to
the projections, said leaf spring having two projections forming a recess between
them.
4. The apparatus according to claim 1, wherein said holding means comprises:
magnets imbedded in upper and lower positions of said latch or in upper and lower
positions of said base, said magnets attracting said latch to said base to hold said
latch at positions corresponding to the locked position and unlocked position of said
latch.
5. The apparatus according to claim 1, wherein said holding means is provided between
the base and the latch of a portion below the pivot shaft supporting the latch in
such a manner that the latch can be turned up and down.
6. The apparatus according to claim 5, wherein said holding means comprises:
a pair of pins attached in opposing relation to the base and the latch of a portion
below the pivot shaft supporting the latch in such a manner that the latch can be
turned up and down;
a pin seat having a recess which engages with the pin on the side of said latch, and
a spring seating flange; and
a pin seat of the lower portion having a recess which engages with the pin on the
side of said base, and a spring seating flange; and
a spring fitted between the spring seating flanges of said upper and lower pin seats,
said latch being held in the locked position or being turned and held in the unlocked
position by moving a straight line connected centers of said pair of pins to mutually
opposing positions with respect to a line connecting a center of turning motion of
said latch and a center of the pin on the side of said base.
7. The apparatus according to claim 6, wherein recesses are formed at opposing positions
in the base and the latch of a portion below the pivot shaft supporting the latch
in such a manner that the latch can be turned up and down, and said spring is provided
by spring seats having pins engaged with these recesses.