U.S. patent number 3,910,617 [Application Number 05/371,576] was granted by the patent office on 1975-10-07 for solenoid operated electric strike.
This patent grant is currently assigned to Square D Company. Invention is credited to William G. Brown, Anthony J. Scalza.
United States Patent |
3,910,617 |
Scalza , et al. |
October 7, 1975 |
Solenoid operated electric strike
Abstract
An electric strike with a pivotally mounted catch which is
locked by a pivotally mounted detent engageable with a pivotally
mounted detent arm controlled by the catch, movement of the detent
being controlled by an electrically energizable solenoid and
moveable core assembly which has a portion of the core extending
outwardly of the solenoid, the core being pivotally interconnected
with the detent and said portion of the core moving inwardly of the
solenoid upon energization of the latter. The detent arm may be
omitted and the detent may, in such case, engage a pin carried by
the catch.
Inventors: |
Scalza; Anthony J. (Bronx,
NY), Brown; William G. (New York, NY) |
Assignee: |
Square D Company (Park Ridge,
IL)
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Family
ID: |
26921855 |
Appl.
No.: |
05/371,576 |
Filed: |
June 20, 1973 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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227895 |
Feb 20, 1972 |
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Current U.S.
Class: |
292/341.16 |
Current CPC
Class: |
E05B
47/0047 (20130101); Y10T 292/699 (20150401) |
Current International
Class: |
E05B
47/00 (20060101); E05C 019/16 () |
Field of
Search: |
;292/144,201,341.16
;70/277,280,281,282,447,448 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Moore; Richard E.
Attorney, Agent or Firm: Brooks Haidt Haffner &
Delahunty
Parent Case Text
This application is a continuation-in-part of our co-pending
application Ser. No. 227,895 entitled SOLENOID OPERATED ELECTRIC
STRIKE and filed Feb. 20, 1972, now abandoned.
Claims
What is claimed is:
1. An electric strike comprising a pivotally mounted catch, a
detent pivotally mounted for movement of a portion thereof from a
first position near said catch to a second position farther from
said catch, means controlled by said catch and engageable with said
portion of said detent in one of said positions for preventing
rotation of said catch and movable with respect to said portion of
said detent in the other position thereof to permit rotation of
said catch, and electrically energizable solenoid with a movable
core therein with a portion thereof extending from said solenoid,
said solenoid, when energized, causing said portion of the core to
move in a direction toward the interior of said solenoid and an
interconnecting member extending from said core to said detent and
pivotally connected at one end thereof to said core and pivotally
connected at the other end thereof to said detent for moving said
detent from said second position to said first position upon
movement of said core in said direction.
2. An electric strike comprising a pivotally mounted catch, a
detent pivotally mounted for movement of a portion thereof from a
first position near said catch to a second position farther from
said catch, means controlled by said catch and engageable with said
portion of said detent in one of said positions for preventing
rotation of said catch and movable with respect to said portion of
said detent in the other position thereof to permit rotation of
said catch, an electrically energizable solenoid with a movable
core therein with a portion thereof extending from said solenoid,
said solenoid, when energized, causing said portion of the core to
move in a direction toward the interior of said solenoid, and a
U-shaped rod pivotally connected at one end to said portion of said
core and at its opposite end to said detent for moving said detent
from said second position to said first position upon movement of
said core in said direction, said rod having its intermediate
portion extending alongside said solenoid.
3. A strike as set forth in claim 2, wherein said means engageable
with said detent comprises a pivotally mounted arm having its pivot
axis parallel to the pivot axis of said catch and having an
projection thereon upstanding therefrom in the direction of said
pivot axis and engageable with said detent in said one position
thereof, said catch having means thereon engageable with said arm
for preventing rotation of said arm with respect to said catch in a
predetermined direction but permitting rotation of said arm with
respect to said catch in a direction opposite to said predetermined
direction.
4. A strike as set forth in claim 3, wherein said projection on
said arm is engageable with said detent in said first position of
the latter.
5. A strike as set forth in claim 3, wherein said projection on
said arm is engageable with said detent in said second position of
the latter.
6. An electric strike as set forth in claim 2, wherein said means
engageable with said detent comprises a projection on said catch
spaced from the pivot axis of said catch and extending therefrom in
the direction of said detent.
7. An electric strike comprising a relatively long and narrow base,
a catch pivotally mounted from said base with its pivot axis
extending in the direction of the length of said base, stop means
on said base for limiting the movement of said catch in a first
direction around the pivot axis thereof, spring means acting
between said base and said catch and urging said catch in said
first direction, an electrically energizable solenoid with an
axially moveable core mounted on said base with the axis thereof
extending substantially parallel to the pivot axis of said catch,
with the solenoid spaced from said catch in the direction of the
length of said base and with a portion of said core extending from
said solenoid on the side thereof opposite from said catch, said
portion of said core moving in a direction toward the interior of
said solenoid upon energization of the latter, a detent pivotally
mounted from said base intermediate said solenoid and said catch
and with the pivot axis thereof extending transversely to the pivot
axis of said catch, a lever pivotally connected at one end to said
portion of said core and extending to and being pivotally connected
to a portion of said detent spaced from the pivot axis thereof,
said lever moving said detent from a first position nearer said
solenoid to a second position nearer said catch upon energization
of said solenoid, spring means urging said detent and said portion
of said core away from said catch and urging said detent into said
first position thereof, an arm pivotally mounted from said base on
the side of said catch nearer said detent and between said catch
and said detent with its pivot axis spaced from the pivot axis of
said catch and extending substantially parallel thereto, said arm
having a projection thereon extending, at least in part, toward
said detent and being free to move with respect to said detent when
the latter is in one of said positions thereof but being engageable
with said detent in the other position thereof to prevent movement
of said arm with respect to said detent, and means on said catch
engageable with said arm for preventing rotation of said catch
around its axis in a direction opposite to said first direction
when said projection on said arm is in engagement with said
detent.
8. A strike as set forth in claim 7, wherein said projection on
said arm engages said detent when the latter is in said second
position.
9. A strike as set forth in claim 7, wherein said projection on
said arm engages said detent when the latter is in said first
position.
10. A strike as set forth in claim 9, wherein said projection on
said arm is L-shaped and the portion thereof spaced from said arm
is spaced from the latter by an amount sufficient to permit said
detent to pass between said arm and said portion when said detent
is in said second position.
11. An electric strike comprising a relatively long and narrow
base, a catch pivotally mounted from said base with its pivot axis
extending transversely to the length of said base, stop means on
said base for limiting movement thereof in a first direction around
the pivot axis thereof, spring means acting between said base and
said catch and urging said catch in said first direction, an
electrically energizable solenoid with an axially moveable core
mounted on said base with the axis thereof extending transversely
to the pivot axis of said catch, with the solenoid spaced from said
catch in the direction of the length of said base and with a
portion of said core extending from said solenoid on the side
thereof opposite from said catch, said portion of said core moving
in a direction toward the interior of said solenoid upon
energization of the latter, a detent pivotally mounted from said
base intermediate said solenoid and said catch and with the pivot
axis thereof extending substantially parallel to the pivot axis of
said catch, a lever pivotally connected at one end to said portion
of said core and extending to and being pivotally connected to a
portion of said detent spaced from the pivot axis thereof, said
lever moving said detent from a first position nearer said solenoid
to a second position nearer said catch upon energization of said
solenoid, spring means urging said detent and said portion of said
core away from said catch and urging said detent into said first
position thereof, an arm pivotally mounted from said base with its
pivot axis spaced from the pivot axis of said catch and extending
substantially parallel thereto, said arm having a projection
thereon extending, at least in part, toward said detent and being
free to move with respect to said detent when the latter is in one
of said positions thereof but being engageable with said detent in
the other position thereof to prevent movement of said arm with
respect to said detent, and means on said catch engageable with
said arm for preventing rotation of said catch around its axis in a
direction opposite to said first direction when said projection on
said arm is in engagement with said detent.
12. A strike as set forth in claim 11, wherein said projection on
said arm engages said detent when the latter is in said second
position.
13. An electric strike comprising a pivotally mounted catch, a
detent pivotally mounted for movement of a portion thereof from a
first position near said catch to a second position farther from
said catch, means controlled by said catch and engageable with said
portion of said detent in one of said positions for preventing
rotation of said catch and movable with respect to said portion of
said detent in the other position thereof to permit rotation of
said catch, an electrically energizable solenoid with a movable
core therein with a portion thereof extending from one end of said
solenoid, said solenoid, when energized, causing said portion of
the core to move in a direction toward the interior of said
solenoid and said solenoid being mounted with its opposite end
adjacent said detent, and interconnecting means pivotally connected
at a first portion thereof to said core and pivotally connected at
a second portion thereof spaced from said first portion in a
direction generally parallel to the direction of movement of said
core to said detent for moving said detent from said second
position to said first position upon movement of said core in said
direction.
14. An electric strike comprising a pivotally mounted catch, a
detent pivotally mounted for movement of a portion thereof from a
first position near said catch to a second position farther from
said catch, means controlled by said catch and engageable with said
portion of said detent in one of said positions for preventing
rotation of said catch and movable with respect to said portion of
said detent in the other position thereof to permit rotation of
said catch, an electrically energizable solenoid with a movable
core therein with a portion thereof extending from said solenoid,
said solenoid being mounted with said portion of said core and said
detent at the same side thereof and said solenoid, when energized,
causing said portion of the core to move in a direction toward the
interior of said solenoid, and a U-shaped rod pivotally connected
at one end to said portion of said core and at its opposite end to
said detent for moving said detent from said second position to
said first position upon movement of said core in said
direction.
15. An electric strike comprising a pivotally mounted catch, a
detent plate pivotally mounted for movement of a portion thereof
from a first position near said catch to a second position farther
from said catch, the pivot axis of said plate extending
transversely to the pivot axis of said catch, said catch having a
projection thereon in the form of a pin which extends generally
parallel to said pivot axis of said catch, said detent plate having
a surface which extends radially from the pivot axis of said plate
and said pin being engageable with said surface of said plate in
one of said positions for preventing rotation of said catch and
movable with respect to said surface of said plate in the other
position thereof to permit rotation of said catch, an electrically
energizable solenoid with a movable core therein with a portion
thereof extending from said solenoid, said solenoid, when
energized, causing said portion of the core to move in a direction
toward the interior of said solenoid, and interconnecting means
pivotally connected at a first portion thereof to said core and
pivotally connected at a second portion thereof spaced from said
first portion in a direction generally parallel to the direction of
movement of said core to said detent plate for moving said detent
plate from said second position to said first position upon
movement of said core in said direction.
16. An electric strike comprising a pivotally mounted catch, a
detent mounted for movement from a first position near said catch
to a second position farther from said catch, means controlled by
said catch and engageable with said detent in one of said positions
for preventing rotation of said catch and movable with respect to
said detent in the other position thereof to permit rotation of
said catch, said means comprising a pivotally mounted arm having
its pivot axis parallel to the pivot axis of said catch and having
an upstanding L-shaped projection thereon engageable with said
detent in said second position thereof and permitting said detent
to pass between said projection and said arm in the first position
of said detent, an electrically energizable solenoid with a movable
core therein with a portion thereof extending from said solenoid,
said solenoid, when energized, causing said portion of the core to
move in a direction toward the interior of said solenoid said
solenoid being mounted with said detent at one side thereof and
with said portion of said core at the opposite side thereof and
interconnecting means pivotally connected to said core and to said
detent for moving said detent from said second position to said
first position upon movement of said core in said direction.
Description
This invention relates to electrically operable door strikes used
either to unlock or lock a door, gate, or other barrier or to stop
or release certain types of moveable devices, upon electrical
energization thereof.
Electrically operable door strikes, also known in the art as
electric strikes, electric releases or electric door openers, are
well known and are used primarily to control the opening of a door
providing access to a space where it is desired to restrict the
persons entering such space. For example, it may be used in
conjunction with an apartment house door, so that a person or
persons can leave the building by withdrawing the door latch
internally and without electrically energizing the strike, but so
that persons may not open the door from the exterior without either
a proper key or electrical energization of the strike by various
means, e.g. by the operation of the push button by a person from
internally of the building or by authorized personnel from
externally of the building. Such a push button can be replaced by
devices such as a card-key control device, an air control switch,
etc.
In some applications, such as in institutions, it is desirable to
lock a door or doors by energization of the strike so that in the
event of power failure and an emergency, such as a fire, the doors
will be unlocked automatically. One embodiment of the invention is
of the type which locks upon energization of the strike and is
applicable to door interlock systems; fire control doors;
institutional fail-safe doors; door control of emergency alarm
systems and control of stop-motion devices.
The strike is located in the door frame where there is very little
space. Therefore, it is very important that the strike and its
operating mechanism occupy as little space as possible. Also, to be
reliable, it is important that the electric coil be able to exert a
substantial force on on the catch holding or releasing mechanism
even though it is small, particularly if the door is being pushed
while the coil is energized. It has been found that as a practical
matter a solenoid and moveable core or plunger type of mechanism
can, for a given size, provide a greater force than an
electromagnet with an armature and yet be simple in
construction.
However, when a solenoid is energized it normally pulls the core or
plunger inwardly of the coil which, while simply connected to
release a catch upon energization of the coil, creates
complications when it is desired to lock the catch upon
energization of the coil. For example, to lock the catch the detent
lever or plate usually moves toward the catch and the catch detent
arm, but if the portion of the solenoid plunger which extends out
of the core faces the catch, the plunger movement is away from the
catch which either requires a reversing mechanism or a more
complicated detent lever and detent arm and additional space.
Also, the plunger of the solenoid usually is confined to movement
in a straight line whereas the detent is pivotally mounted which
means that the point of connection thereon moves in an arc so that
the plunger cannot be connected directly thereto if binding of the
plunger is to be avoided.
In accordance with the preferred embodiment of the invention, the
detent for the catch of a strike moves toward the catch, but the
exposed portion of the solenoid plunger faces away from the catch
and is pivotally joined to the detent so that energization of the
coil of the solenoid causes the detent to move away from the coil.
With such a construction, the mechanism used to control the catch
may be as simple as that previously used and yet the space
requirements are kept to a minimum. Although such construction is
particularly advantageous for a strike in which the catch is locked
upon energization of the solenoid, it is also useful for releasing
a catch upon energization without causing complexity in the catch
control mechanism.
In another embodiment of the invention the detent, strike and
solenoid and plunger construction are the same as in the first
embodiment, but the exposed portion of the plunger faces toward the
catch and the detent and is connected to the detent in the same
manner as it is connected thereto in the first embodiment so as to
avoid binding of the plunger.
One object of the invention is to provide a solenoid and core
operated electric strike which is simple in construction, small in
size, reliable in operation and which can be energized by
alternating or direct current at any desired voltage.
Other objects and advantages of the invention will be apparent from
the following detailed description of presently preferred
embodiments thereof, which description should be considered in
conjunction with the accompanying drawings in which:
FIGS. 1 and 2 are perspective views of the preferred embodiment of
the invention respectively showing the catch in the locked position
and in the released position;
FIG. 3 is a fragmentary, perspective view of a modified form of the
embodiment shown in FIGS. 1 and 2, in which the catch is released
upon energization of the solenoid;
FIGS. 4 and 5 are perspective views of a modified form of the
embodiment shown in FIGS. 1 and 2 in which the solenoid is located
in a different position with respect to the catch; and
FIGS. 6-9 are perspective views of modified forms of the embodiment
shown in FIGS. 1 and 2 in which the catch is released upon
energization of the solenoid.
With reference to FIG. 1, a catch 10 is pivotally mounted on a
shaft 11 which is surrounded by spring 12, which urges the catch
face outwardly of the strike housing which comprises a relatively
long and narrow base 13 with upstanding walls 14, 15, 16, 17 and
18. The housing may comprise additional walls and the mounting
plate for the strike has been omitted for ease in illustration. The
face of the catch 10 engages a latch 19 which normally is carried
by a door and which is moveable in the direction of the arrow 20 to
disengage it from the catch 10. When the latch 19 is disengaged
from the catch 10, the latch 19, and the portion of the door on
which it is mounted, is moveable in the direction of the arrow 20a.
The cooperation of the catch 10 with the latch 19 is well known in
the art, and when the catch 10 is locked, the door carrying the
latch 19 cannot be opened until the latch is moved in the direction
of the arrow 20. However, when the catch 10 is released, the door
can be opened without withdrawing the latch 19, because the catch
10 is permitted to move around the shaft 11 into the position
thereof shown in FIG. 2.
The ends of the shaft 11 are supported by the walls 15 and 16, and
the wall 16 has a curved slot 21 therein through which a pin 22,
mounted on the catch 10, extends. Outward movement of the catch is
limited by engagement by the pin 22 with the end wall of the slot
21, and inward movement of the catch 10 is limited by engagement of
the pin 22 with the opposite end wall of the slot 21.
An arm 23 is pivotally mounted at 24 on the wall 16 and has an
upstanding projection 25, which is engageable with a detent 26 when
it is in the position shown in FIG. 1. The detent 26 is pivotally
mounted at 27 on the wall 17, and is similarly pivotally mounted on
the opposite end on the wall 18. Thus, the detent 26 can move, at
its end spaced from the axis 27, toward and away from the catch 10,
and preferably movement of the detent 26 toward the catch 10 is
limited by a fixed pin 28 extending upwardly from the base 13.
The base 13 carries a solenoid and core assembly 29 which comprises
a solenoid 30 which can be continuously or discontinuously
energized, a frame 31, and a moveable core 32 extending axially of
the solenoid 30. A yoke 33 is mounted on the end of the core 32,
and a washer 34 is mounted between the yoke 33 and the core 32. The
core 32 is surrounded by a spring 35 which urges the core outwardly
of the interior of the solenoid 30.
The yoke 33 is connected to a portion of the detent 26 by a lever
in the form of a U-shaped rod 36, which is pivotally connected to
the yoke 33 at one end and is pivotally connected to the detent 26
at the opposite end and at a portion of the detent 26 spaced from
its pivot axis, the intermediate portion of the rod 36 extending
alongside the solenoid 30. The rod 36 may be retained in place by
the wall 17 or in any other manner, such as by flattening one end
thereof as shown in FIGS. 4 and 5.
In FIG. 1 the parts of the strike are shown in the positions which
they assume when the solenoid 30 is energized and in FIG. 2 they
are shown in the positions they assume when the solenoid is
de-energized. Thus, as shown in FIG. 1, with the solenoid 30
energized, the detent 26 is against the pin 28 and in a position in
which it engages the projection 25 on the arm 23 when an attempt is
made to rotate the catch 10 around the shaft 11, the pin 22
engaging the arm 23. Accordingly, the catch 10 is prevented from
rotating around the shaft 11 and is locked.
However, when the solenoid 30 is de-energized, the spring 35 moves
the core 32, the rod 36 and the detent 26 to the positions shown in
FIG. 2, so that if pressure is applied to the catch 10 to cause it
to rotate around the shaft 11, the projection on the arm 23 is free
to move past the detent 26 so that the catch 10 may be withdrawn to
the position shown in FIG. 2. Accordingly, the embodiment shown in
FIGS. 1 and 2 is one in which the catch 10 is locked when the
solenoid 30 is energized and is released when the solenoid 30 is
not energized.
When it is desired to employ the parts shown in FIGS. 1 and 2 to
cause the catch 10 to be locked when the solenoid is de-energized
and to be released when the solenoid is energized, the arm 23 may
be modified as shown in FIG. 3. In FIG. 3, the arm 23 is replaced
by an arm 37 which has an L-shaped projection 38 extending
therefrom. One portion 39 of the projection 38 is engageable with
the detent 26 when the solenoid 30 is de-energized, and the parts
are in the position shown in FIG. 3. However, the spacing between
he portion 39 and the main body of the arm 37 is sufficient to
permit the end of the detent 26 to pass therebetween when the
detent 26 is moved by the solenoid core to the position shown in
FIG. 1 which permits the arm 37 to rotate about its axis 24, and
therefore, permits the catch 10 to rotate about its pivot axis to
the position shown in FIG. 2. It will be noted from FIG. 3 that to
provide the necessary clearance for the projection 38, the rod 36
is mounted on the opposite side of the solenoid 30 from that shown
in FIGS. 1 and 2 and the detent 26a is cut away at 26b, it being
necessary for the projection 38 to move substantially to the base
13 to permit adequate movement of the catch 10.
The embodiments shown in the preceding figures are particularly
suitable for installation where the depth of the door frame is
relatively small. However, in some applications, the door frame
depth is sufficient to permit reorientation of the solenoid and
core assembly 29 to the positions shown in FIGS. 4 and 5. In the
embodiments shown in FIGS. 4 and 5 the shaft 11, and hence the
pivot axis of the catch 10, is disposed transversely to the length
of the base 40 of the strike housing, and the detent arm 41 is
pivotally mounted at 42 on the wall 42a. Preferably, the embodiment
shown in FIGS. 4 and 5 is provided with a second detent arm 43
similar to the arm 41 and similarly mounted on the wall 45. Outward
movement of the catch 10 may be limited in any well known manner,
such as by an ear 44 on the side wall 45 of the housing and
engageable with the arm 43, each of the arms 41 and 43 having a
slot 46 (FIG. 5) for receiving the pin 22.
The solenoid and moveable core assembly 29 in FIGS. 4 and 5 is
identical with the solenoid and core assembly 29 shown in the
preceding Figures, and the detent 26 is mounted and operates
similarly to the detent 26 shown in the preceding Figures. The core
32 is connected to the detent 26 by the U-shaped rod 36 and may be
retained in the yoke 33 by a flat 49 at one end. The arms 41 and 43
have projections 47 and 48 which are engageable with the detent 26
when the solenoid 30 is energized and which pass by the detent 26
when the solenoid 30 is de-energized. Thus, when the solenoid is
energized, the detent 26 is in the position shown in FIG. 4 and
engages the projections 47 and 48 preventing movement of the catch
10 around the shaft 11 by reason of the arms 41 and 43 and the pins
22. However, when the solenoid 30 is de-energized, the detent 26
assumes the position shown in FIG. 5 so that the arms 41 and 43 are
free to move with the catch 10 permitting the catch 10 to move to
the released position shown in FIG. 5. The catch 10 is returned to
the outwardly extending position shown in FIG. 4 by means of the
spring 12.
As described hereinbefore, the embodiment of FIG. 3 is similar to
the embodiment shown in FIGS. 1 and 2 in that the exposed portion
of the core 32 faces away from the detent 26a. However, it differs
therefrom in that the catch 10 is locked when the solenoid 30 is
de-energized. A further embodiment in which the catch 10 is locked
when the solenoid 30 is de-energized but in which the solenoid and
core assembly 29 is reversed, is illustrated in FIGS. 6 and 7.
Except for the reversal of the assembly 29 and the replacement of
the rod 36 by a shorter rod 50, the structure shown in FIGS. 6 and
7 is the same as that shown in FIGS. 1 and 2.
In the embodiment shown in FIGS. 6 and 7, the solenoid and core
assembly 29 is mounted on the base 13 with the exposed portion of
the core or plunger 32 facing the detent 26, and the yoke 33 on the
end of the core or plunger 32 is connected to the detent 26 by
means of a U-shaped rod 50, similar to the U-shaped rod 36 shown in
FIGS. 1-3. The action of the detent 26, the catch 10, the arm 23
and the pin 22 is the same as that described in connection with
FIGS. 1 and 2. Thus, with the solenoid and core assembly 29
de-energized, the detent 26 assumes the position shown in FIG. 6
and locks the catch 10. When the solenoid and core assembly 29 is
energized, the detent 26 is moved by the core 32 and the rod 50 to
the position shown in FIG. 7, thereby permitting the arm 23, and
hence the catch 10, to rotate.
If desired, the detent arm 23 may be omitted and the detent may
directly engage the pin 22 on and controlled by the catch 10. FIGS.
8 and 9 illustrate an embodiment similar to the embodiment shown in
FIGS. 6 and 7, but differing therefrom primarily in that the detent
arm 23 has been omitted and the pin 22 on the catch 10 is directly
engaged by the detent 51.
In FIGS. 8 and 9 the solenoid core assembly is mounted on a
relatively long and narrow base 53 having upstanding walls 54, 55,
56, 57 and 58, such base and walls forming a housing for the
various parts. The housing may comprise additional walls which have
been omitted in the drawings for ease of illustration. A portion of
the mounting plate 59 for the strike is shown in FIGS. 8 and 9.
The operation of the embodiment shown in FIGS. 8 and 9 is
essentially the same as the operation of the embodiment shown in
FIGS. 6 and 7. The detent 51 is normally urged into the position
shown in FIG. 8 by reason of its connection to the yoke 33 through
the U-shaped rod 50, and is limited in its movement away from the
solenoid and core assembly 29 by reason of its engagement with the
upstanding wall 56. In the position shown in FIG. 8, the nose
portion 60 of the detent 51 is in the path of the pin 22 secured to
the catch 10 so that inward movement of the catch 10 is prevented
by the nose portion 60 of the detent 51.
When the solenoid 30 is energized, the core 32 thereof moves
inwardly of the solenid 30, thereby moving the detent 51 into the
position shown in FIG. 9. In such position, the nose 60 is out of
the path of the pin 22 thereby permitting the catch 10 to be moved
inwardly to the position shown in FIG. 9. Maximum inward movement
of the catch 10 is limited by reason of the engagement of the pin
22 with a portion of the upstanding wall 56.
It will be apparent to those skilled in the art that various
modifications may be made without departing from the principles of
the invention. For example, although it is preferred because of
simplicity to employ the bent rod 36 for interconnecting the
solenoid core and the detent, nevertheless, another type of linkage
may be interposed between the core and the detent.
* * * * *