CN117628333A - Device for fixing a defibrillator - Google Patents

Abstract

The present invention provides an apparatus for securing a defibrillator, comprising: a base assembly; and a patch panel removably mountable on the base assembly, the patch panel to be fixedly mounted to the defibrillator; wherein, the base subassembly includes: a base including a bottom plate; a movable unit on which the adapter plate can be removably mounted; an actuating mechanism mounted on the base and for driving the movable unit toward the outside of the base; a locking mechanism that locks the movable unit that moves to the inside of the base in place; and a stopper mechanism that prevents movement of the adapter plate mounted on the movable unit. The device for fixing the defibrillator according to the invention has simple structure and easy operation, and can quickly and conveniently fix the defibrillator on the ambulance firmly.

Description

Device for fixing a defibrillator

Technical Field

The present invention relates to defibrillators, and more particularly to devices for immobilizing defibrillators.

Background

In emergency situations, the defibrillator needs to be quickly taken out after being placed in an ambulance and transported to the site, and the defibrillator needs to be quickly and conveniently fixed on the ambulance and kept running during the process of transporting the patient to the hospital so as to monitor, defibrillate, pace and the like the patient. In this process, how to quickly and easily secure the defibrillator to the ambulance is critical to successfully save the patient's life. The existing equipment for fixing the defibrillator is generally complex in structure and complex in operation, and the defibrillator is difficult to fix the defibrillator on an ambulance fast and conveniently.

Accordingly, there is a need for improvements in the art for devices for immobilizing defibrillators.

Disclosure of Invention

It is an object of the present invention to provide a device for immobilizing a defibrillator which overcomes at least one of the above-mentioned drawbacks of the prior art.

According to one aspect of the present invention, there is provided an apparatus for immobilizing a defibrillator, comprising:

a base assembly; and

a patch panel removably mountable on the base assembly, the patch panel to be fixedly mounted to the defibrillator;

wherein, the base subassembly includes:

a base including a bottom plate;

a movable unit on which the adapter plate can be removably mounted;

an actuating mechanism mounted on the base and for driving the movable unit toward the outside of the base;

a locking mechanism that locks the movable unit that moves to the inside of the base in place; and

a stop mechanism that prevents the movement of an adapter plate mounted on the movable unit.

Preferably, the movable unit comprises a support plate for receiving the adapter plate;

the actuating mechanism includes a guide rod fixedly supported on the base plate, a slider slidably disposed on the guide rod, and a first spring that is sleeved on the guide rod and applies a spring force to the slider so as to push the slider along the guide rod; and

the support plate is fixed to the slider so as to move together with the slider.

Preferably, the locking mechanism includes a locking block provided on the base plate, a locking lever mounted on the movable unit and engageable with the locking block, and an operating member for operating the locking lever to disengage the locking lever from the locking block.

Preferably, the locking mechanism comprises:

two locking blocks arranged on the bottom plate;

two L-shaped lock levers mounted on the movable unit, each of the L-shaped lock levers being formed with a hook portion near a first end of the corresponding lock block, and each of the L-shaped lock levers being pivotably mounted on the movable unit at a corner portion;

a pressing member mounted on the movable unit and capable of pressing a second end of each of the L-shaped locking bars; and

and a second spring acting on each L-shaped locking rod, wherein each L-shaped locking rod is pivoted by the second spring, so that the hook part is hooked on the corresponding locking block.

Preferably, the support plate is provided with a handle, and each of the L-shaped lock lever and the pressing member is mounted on the handle.

Preferably, the pressing member is provided inside the handle.

Preferably, the base further includes side plates fixedly disposed at both sides of the bottom plate, and the stopper mechanism includes:

a boss provided on the support plate, the boss being insertable into a positioning hole formed on the adapter plate to restrict horizontal movement of the adapter plate with respect to the support plate; and

a stopper rod provided on each of the side plates and extending toward the inside of the base, respectively, the stopper rod having a distance to the support plate in a vertical direction to allow the movable unit and the adapter plate mounted on the movable unit to be horizontally movable, and to restrict the adapter plate from moving vertically with respect to the support plate when the movable unit and the adapter plate move to the inside of the base.

Preferably, the top ends of the convex columns can be designed into hemispherical shapes.

Preferably, the adapter plate is provided in an i-shape, and a stepped recess is provided on each arm of the adapter plate, the stopper rod being respectively received in the corresponding stepped recess when the movable unit and the adapter plate are moved to the inside of the base.

Preferably, a guide groove corresponding to an outer contour of the adapter plate is provided on the support plate.

Preferably, a wire guard is provided at a rear end of the base, and a wire guide is provided on the wire guard.

Preferably, a dust-proof wall is provided on the base, which together with the base and the support plate defines an enclosed space accommodating the actuation mechanism.

Preferably, the apparatus for fixing a defibrillator further comprises a separate lock preventing the movable unit from being accidentally ejected, the movable unit further comprising a front end plate provided at a front end of the support plate, the separate lock comprising a latch provided on the front end plate and a stopper provided on the bottom plate for blocking the latch.

The device for fixing the defibrillator according to the invention has simple structure and easy operation, and can quickly and conveniently fix the defibrillator on the ambulance firmly.

Drawings

Fig. 1 schematically shows in an exploded perspective view an apparatus for securing a defibrillator according to the present invention, the handle and the components of the locking mechanism mounted on the handle not being shown in fig. 1;

fig. 2 schematically shows in perspective view a base assembly of a device for securing a defibrillator according to the present invention, wherein a movable unit of the base assembly is removed to show internal structure;

FIG. 3 is a perspective view similar to FIG. 2, but with the addition of a wire guard;

fig. 4 schematically shows in perspective view a movable unit of a device for immobilizing a defibrillator according to the present invention;

fig. 5 shows schematically the movable unit of fig. 4 in a bottom side perspective view;

fig. 6 schematically illustrates in perspective view a base assembly of a device for securing a defibrillator according to the present invention, with portions broken away to show internal structure;

fig. 7 shows schematically in a partial perspective view an independent lock of a device for immobilizing a defibrillator according to the invention;

fig. 8 schematically shows in perspective view that an adapter plate of the device for fixing a defibrillator according to the present invention is mounted to the bottom of the defibrillator;

fig. 9 schematically shows in perspective view an apparatus for securing a defibrillator according to the present invention, wherein the movable unit is ejected from the base and the adapter plate has not been placed on the movable unit;

fig. 10 is a top view of the apparatus for immobilizing a defibrillator of fig. 9; and

fig. 11 shows schematically in a perspective view an apparatus for securing a defibrillator according to the present invention, wherein a movable unit is inserted into a base and an adapter plate has been fixedly held on the movable unit.

Detailed Description

Specific embodiments of the invention will be described in detail below with reference to the drawings, but it should be understood that the drawings are for illustration only and are not to be construed as limiting the invention.

Fig. 1 schematically shows in an exploded perspective view an apparatus for securing a defibrillator according to the present invention, the handle and the components of the locking mechanism mounted on the handle not being shown in fig. 1; fig. 2 schematically shows in perspective view a base assembly of a device for securing a defibrillator according to the present invention, wherein a movable unit of the base assembly is removed to show internal structure; FIG. 3 is a perspective view similar to FIG. 2, but with the addition of a wire guard; fig. 4 schematically shows in perspective view a movable unit of a device for immobilizing a defibrillator according to the present invention; and fig. 5 shows schematically the movable unit of fig. 4 in a bottom side perspective view. As shown in fig. 1-5, a device 1 for securing a defibrillator according to the present invention generally includes a base assembly 3 and an adapter plate 5 removably retainable on the base assembly 3. The base assembly 3 comprises a base 7, a movable unit 9, an actuating mechanism 11 for driving the movable unit 9 towards the outside of the base 7, a locking mechanism 13 for locking the movable unit 9 moved to the inside of the base 7 in place, and a stop mechanism 15 for preventing movement of the adapter plate 5 mounted on the movable unit 9.

As shown in fig. 1 to 3, the base 7 includes a bottom plate 17 and side plates 19 fixedly provided on both sides of the bottom plate 17. The base plate 17 may be fixedly mounted on the ambulance, for example, both sides of the base plate 17 may have side wings 21 extending protrusively with respect to the side plates 19, each of the side wings 21 having a through hole 23, and the base plate 17 may be fixedly mounted on the ambulance by a screw (not shown) passing through the through hole 23.

As shown in fig. 1, 4 and 5, the movable unit 9 includes a support plate 25 that can be driven by the actuating mechanism 11 and is substantially flat, and a plurality of mounting holes 27 are formed on both sides of the support plate 25, respectively. As shown in fig. 1, 2 and 3, the actuating mechanism 11 for driving the movable unit 9 toward the outside of the base 7 includes a guide rod 29 fixedly supported at both ends thereof on the base plate 17 through a bearing 28, a slider 31 through which the guide rod 29 passes so as to be slidable along the guide rod 29, and a first spring 33 that is fitted over the guide rod 29 and applies a spring force to the slider 31 so as to push the slider 31 toward the outside of the base 7 along the guide rod 29. The actuating mechanism 11 including the guide rod 29, the slider 31 and the first spring 33 can withstand a dynamic load of higher strength with higher reliability. In the preferred embodiment, a pair of relatively parallel arranged actuating mechanisms 11 are shown, but it will be appreciated that it is possible to provide only one actuating mechanism or more actuating mechanisms. The support plate 25 may be fixed to the slider 31 by screws (not shown) screwed into the screw holes 35 on the slider 31 through the mounting holes 27 on the support plate 25 of the movable unit 9 so that the support plate 25 may move together with the slider 31. In this way, the support plate 25 (i.e., the movable unit 9) can be automatically and rapidly ejected under the action of the first spring 33.

As shown in fig. 5 and 6 in particular, the locking mechanism 13 that locks the movable unit 9 that moves to the inside of the base 7 in place includes a lock block provided on the base plate 17, a lock lever that is mounted on the movable unit 9 and is capable of engaging with the lock block to lock the movable unit 9 in the operating position, and an operating member for operating the lock lever to disengage the lock lever from the lock block. In the preferred embodiment, there are two lock blocks 37 provided on the base plate 17, and two L-shaped lock levers 39 mounted on the movable unit 9, each L-shaped lock lever 39 is formed with a hook 41 near a first end of the corresponding lock block 37, and each L-shaped lock lever 39 is pivotally mounted on the movable unit 9 at an intermediate corner by a pivot 43, in the preferred embodiment each L-shaped lock lever 39 is mounted on a handle 45 for the support plate 25. The operating means comprise pressing means 47 mounted on the movable unit 9, in particular on the handle 45, and able to press the second end of each L-shaped locking lever 39. Each L-shaped lock lever 39 pivots about the pivot shaft 43 under the loading of the second spring 49 so that the hook 41 formed at the first end of the lock lever is hooked on the corresponding lock block 37 and so that the second end of the lock lever abuts against the pressing member 47. In this way, pressing the second end of the L-shaped lock lever 39 by the pressing member 47 causes the L-shaped lock lever 39 to pivot against the action of the second spring 49, so that the hook 41 of the first end of the L-shaped lock lever 39 disengages the lock block 37 to allow the movable unit 9 to move together with the slider 31. The L-shaped locking lever 39 is designed as a spring-loaded lever which converts a linear motion into a rotational motion, and reduces friction between the hook 41 and the locking block 37 during unlocking, so that unlocking is smoother and more convenient. In order to facilitate movement of the hook 41 through the lock block 37 when the movable unit 9 is pushed back inside the base 7, the hook 41 has an inclined surface 42 to be in contact with the lock block 37 to guide movement of the hook 41.

For ease of handling by the healthcare worker, the support plate 25 may have a recess 48 formed therein for mounting the handle 45 in the recess 48, and correspondingly a further recess 50 formed in the base plate 17. The pressing member 47 may be preferably provided inside the handle 45 to prevent the hook 41 of the first end of the L-shaped locking lever 39 from being separated from the locking block 37 by an accidental touching of the pressing member 47.

As shown in fig. 1 to 4 and 6, the stopper mechanism 15 which prevents the movement of the adapter plate 5 mounted on the movable unit 9 includes a boss 51 provided on the support plate 25, and the boss 51 is inserted into a positioning hole 53 formed on the adapter plate 5, thereby restricting the horizontal movement of the adapter plate 5 with respect to the support plate 25. In the preferred embodiment, four studs 51 are provided on the support plate 25 and corresponding four locating holes 53 are provided on the adapter plate 5, but it should be understood that the number of studs 51 and corresponding locating holes 53 may be less or greater than four. The top end of each boss 51 may be designed as a hemisphere to achieve rapid and precise introduction of the positioning hole 53 on the adapter plate 5, and thus rapid placement of the defibrillator. Furthermore, in the preferred embodiment, the posts 51 are generally cylindrical and the corresponding locating holes 53 are circular holes, it being understood that the posts 51 may be other shapes such as prismatic and the locating holes 53 may be square holes, for example. Furthermore, it is also possible to provide the stud on the adapter plate and the positioning hole on the support plate. The stopper mechanism 15 that prevents the transfer plate 5 mounted on the movable unit 9 from moving further includes stopper rods 55 that are provided on the two side plates 19 of the base 7, respectively, and extend toward the inside of the base 7, the stopper rods 55 having a distance to the support plate 25 in the vertical direction to allow the movable unit 9 and the transfer plate 5 mounted on the movable unit 9 to be horizontally movable, and restrict the transfer plate 5 from moving vertically with respect to the support plate 25 after the transfer plate 5 moves horizontally below the stopper rods 55 (i.e., when the movable unit 9 and the transfer plate 5 are moved to the inside of the base 7). For this purpose, two stop bars 55 may be provided on each side plate 19 at a distance, the adapter plate 5 is preferably provided in an i-shape, and a stepped recess 57 is provided on each arm of the i-shaped adapter plate 5, each stop bar 55 being received in a corresponding stepped recess 57, respectively, to prevent the adapter plate 5 from moving vertically relative to the support plate 25 when the movable unit 9, in which the adapter plate 5 is placed, is inserted inside the base 7.

Fig. 8 schematically shows in perspective view that an adapter plate of the device for fixing a defibrillator according to the present invention is mounted to the bottom of the defibrillator. As shown in fig. 8, the i-shaped interposer 5 is fixed to the bottom of the defibrillator 61 by a plurality of screws 59 so as to integrate the i-shaped interposer 5 with the defibrillator 61. In order to uniformly stress the i-shaped interposer 5 and the defibrillator 61 when the i-shaped interposer 5 is connected to the defibrillator 61, a plurality of cushion pads 63 may be provided on a surface of the i-shaped interposer 5 in contact with the defibrillator 61 as shown in fig. 1. Similarly, as shown in fig. 8, a plurality of additional cushion pads 65 may be provided on the surface of the i-shaped adapter plate 5 contacting the support plate 25. When the integrated i-shaped adapter plate 5 and defibrillator are mounted on the support plate 25, the defibrillator may affect the rapid alignment of the boss 51 on the support plate 25 with the positioning hole 53 on the adapter plate 5, and thus, a guide groove 66 corresponding to the outer contour of the adapter plate 5 may be provided on the support plate 25 to facilitate the rapid alignment of the boss 51 with the positioning hole 53.

As shown in fig. 1 and 3, a wire guard 67 may also be provided at the rear end of the base 7, the wire guard 67 being provided with wire guides for passing wires for powering the defibrillator 61 therethrough. The wire guard 67 may be used to house wires and prevent medical personnel from getting an electric shock by mistake when the defibrillator 61 is in operation, while also avoiding unstable wiring of the defibrillator in the shock environment of the ambulance.

A dust wall 71 may also be provided on the base 7, the dust wall 71 defining with the base 7 and the support plate 25 a generally enclosed space to accommodate the actuation mechanism 11 such that the components of the actuation mechanism 11 are not exposed to the external environment as shown in fig. 10. In this way, external dust can be prevented from contaminating the components of the actuation mechanism, while also preventing blood or body fluids from being splattered to the surfaces of the components of the actuation mechanism and not being cleanable. The dust wall 71 may be integrally formed with the base 7 and is preferably integrally cast as an aluminum frame.

Although the locking mechanism 13 has been provided, a separate lock 73 may be additionally provided in order to prevent the pressing member on the misoperation handle from causing the fixing failure of the adapter plate and the defibrillator mounted on the movable unit 9. Fig. 7 schematically shows in a partial perspective view the independent lock of the device for immobilizing a defibrillator according to the invention. As shown in fig. 7, the independent lock 73 includes a lock body 77 mounted on a front end plate 75 of the movable unit 9, a lock tongue 79 mounted on the lock body 77, and a stopper 81 mounted on the bottom plate 17 of the base 7. The front end plate 75 of the movable unit 9 is mounted on the front end of the support plate 25 of the movable unit 9. The independent lock 73 also includes a key 83. When not in use, the key 83 may be inserted into a key receiver 85 on the front end plate 75; when necessary, the key 83 is pulled out from the key receiving part 85 and inserted into the lock body 77 to rotate the lock body 77 and the locking tongue 79 mounted thereon. When the lock tongue 79 rotates to the rear of the stopper 81 on the bottom plate 17, the movable unit 9 cannot be ejected even if the pressing member is operated. Only after the lock tongue 79 is rotated to be moved away from behind the stopper 81 on the bottom plate 17, the movable unit 9 is ejected by operating the pressing member, so that any possible erroneous operation can be prevented.

Fig. 9 schematically shows in perspective view an apparatus for securing a defibrillator according to the present invention, wherein the movable unit is ejected from the base and the adapter plate has not been placed on the movable unit; fig. 10 is a top view of the device for securing a defibrillator in the state of fig. 9; and fig. 11 shows schematically in a perspective view an apparatus for securing a defibrillator according to the present invention, wherein the movable unit is inserted into the base and the adapter plate has been fixedly held on the movable unit. The operation of the device for immobilizing a defibrillator according to the present invention will be described below with reference to fig. 9-11. In order to clearly show the operation of the device for immobilizing a defibrillator according to the present invention, the defibrillator 61 mounted on the adapter plate 5 is removed in fig. 9-11.

The device for fixing a defibrillator according to the present invention is normally fixedly mounted on an ambulance by means of screws (not shown) passing through holes 23 in wings 21 extending protrusively from both sides of bottom plate 17. When it is desired to use the defibrillator, a healthcare worker first pulls out key 83 and inserts into lock body 77 to rotate lock body 77 and locking tab 79 mounted thereon such that locking tab 79 moves away from behind stop 81 on base 17. Subsequently, the healthcare worker holds the handle 45 to press the pressing member 47, causing the L-shaped locking lever 39 to pivot against the action of the second spring 49, so that the hook portion 41 of the first end of the L-shaped locking lever 39 is disengaged from the locking block 37. As a result, the movable unit 9 including the support plate 25 and the front end plate 75 is automatically and rapidly ejected from the base 7 to the outside of the base 7 by the first spring 33 abutting against the slider 31. At this time, as shown in fig. 9 and 10, the support plate 25 is moved to a position where the stopper rod 55 on the side plate 19 of the base 7 does not interfere with the insertion of the boss 51 on the support plate 25 into the positioning hole 53 on the i-shaped adapter plate 5. Then, according to the indication of the guide groove 66, the boss 51 on the support plate 25 is quickly aligned with the positioning hole 53 on the adapter plate 5 and inserted therein, thereby mounting the integrated i-shaped adapter plate 5 and defibrillator on the support plate 25. Subsequently, the mobile unit 9 with the i-shaped adapter plate 5 and the defibrillator is pushed back inside the base 7 against the action of the first spring 33 until the hook 41 of the L-shaped locking lever 39 of the locking mechanism 13 hooks onto the corresponding locking block 37 under the action of the second spring 49. At this time, the movable unit 9 equipped with the i-shaped adapter plate 5 and the defibrillator is moved to a position where, as shown in fig. 11, each stopper rod 55 on the side plate 19 of the base 7 is received in a corresponding stepped recess 57 on each arm of the i-shaped adapter plate 5 to prevent the adapter plate 5 from moving vertically with respect to the support plate 25. Finally, the lock tongue 79 on the lock body 77 is turned behind the stopper 81 on the bottom plate 17 by the key 83. Thus, the defibrillator can be conveniently, quickly, firmly and reliably fixed on the ambulance.

While the invention has been described in detail in connection with the preferred embodiments thereof, it should be understood that this detailed description is merely illustrative of the invention and is not intended to be limiting. The scope of the invention is defined by the claims.

Claims (13)

1. An apparatus for securing a defibrillator, comprising:

a base assembly (3); and

-an adapter plate (5) removably mountable on the base assembly (3), the adapter plate (5) to be fixedly mounted to the defibrillator;

wherein the base assembly (3) comprises:

a base (7) comprising a bottom plate (17);

-a movable unit (9), the adapter plate (5) being removably mountable on the movable unit (9);

an actuating mechanism (11) mounted on the base (7) and for driving the movable unit (9) towards the outside of the base (7);

a locking mechanism (13) that locks the movable unit (9) that moves to the inside of the base (7) in place; and

a stop mechanism (15) for preventing the movement of the adapter plate (5) mounted on the movable unit (9).

2. The device for immobilizing a defibrillator according to claim 1, characterized in that the mobile unit (9) comprises a support plate (25) for housing the adapter plate (5);

the actuating mechanism (11) comprises a guide rod (29) fixedly supported on the base plate (17), a slider (31) slidably arranged on the guide rod (29), and a first spring (33) which is sleeved on the guide rod (29) and applies a spring force to the slider (31) so as to push the slider (31) along the guide rod (29); and

the support plate (25) is fixed to the slider (31) so as to move together with the slider (31).

3. The apparatus for fixing a defibrillator according to claim 1, wherein the locking mechanism (13) comprises a lock block provided on the base plate (17), a lock lever mounted on the movable unit (9) and engageable with the lock block, and an operating member for operating the lock lever to disengage the lock lever from engagement with the lock block.

4. The device for immobilizing a defibrillator according to claim 2, wherein the locking mechanism (13) comprises:

two locking blocks (37) arranged on the bottom plate (17);

two L-shaped lock levers (39) mounted on the movable unit (9), each of the L-shaped lock levers (39) being formed with a hook portion (41) near a first end of the corresponding lock block (37), and each of the L-shaped lock levers (39) being pivotably mounted on the movable unit (9) at a corner portion;

a pressing member (47) mounted on the movable unit (9) and capable of pressing a second end of each of the L-shaped lock levers (39); and

-a second spring (49) acting on each L-shaped locking lever (39), respectively, said second spring (49) pivoting each L-shaped locking lever (39) so as to cause the hooking portion (41) to hook on the corresponding locking block (37).

5. The apparatus for immobilizing a defibrillator according to claim 4, wherein the supporting plate (25) is equipped with a handle (45), and each of the L-shaped locking lever (39) and the pressing member (47) is mounted on the handle (45).

6. The device for immobilizing a defibrillator according to claim 5, wherein the pressing member (47) is provided inside the handle (45).

7. The device for fixing a defibrillator according to claim 2, wherein the base (7) further comprises side plates (19) fixedly arranged on both sides of the bottom plate (17), and wherein the stop mechanism (15) comprises:

a boss (51) provided on the support plate (25), the boss (51) being insertable into a positioning hole (53) formed on the adapter plate (5) to restrict horizontal movement of the adapter plate (5) relative to the support plate (25); and

a stopper rod (55) provided on each of the side plates (19) and extending toward the inside of the base (7), respectively, the stopper rod (55) having a distance to the support plate (25) in a vertical direction to allow the movable unit (9) and the adapter plate (5) mounted on the movable unit (9) to be horizontally movable, and to restrict the adapter plate (5) from moving vertically relative to the support plate (25) when the movable unit (9) and the adapter plate (5) move to the inside of the base (7).

8. The device for immobilizing a defibrillator according to claim 7, wherein the top end of the boss (51) is designed to be hemispherical.

9. The device for fixing a defibrillator according to claim 7, wherein the adapter plate (5) is provided in an i-shape, and a stepped recess (57) is provided on each arm of the adapter plate (5), the stopper bars (55) being received in the respective stepped recesses (57) when the movable unit (9) and the adapter plate (5) are moved to the inside of the base (7), respectively.

10. The device for fixing a defibrillator according to claim 7, characterized in that a guide groove (66) corresponding to the outer contour of the adapter plate (5) is provided on the support plate (25).

11. The apparatus for fixing a defibrillator according to claim 1, wherein a wire guard (67) is provided at the rear end of the base (7), and a wire guide is provided on the wire guard (67).

12. The device for immobilizing a defibrillator according to claim 2, characterized in that a dust-proof wall (71) is provided on the base (7), the dust-proof wall (71) defining, together with the base (7) and the support plate (25), an enclosed space housing the actuation mechanism (11).

13. The apparatus for fixing a defibrillator according to claim 2, further comprising a separate lock (73) for preventing the movable unit (9) from being accidentally ejected, the movable unit (9) further comprising a front end plate (75) provided at a front end of the support plate (25), the separate lock (73) comprising a latch (79) provided on the front end plate (75) and a stopper (81) provided on the bottom plate (17) for blocking the latch (79).