Locking device

Abstract

This locking device offers improved convenience by allowing unlocking through multiple operations. [Solution] The locking device 100 is switchable between a locked state and an unlocked state, and includes a first cam 2, a second cam 3, and a first spring 51. The first cam 2 and the second cam 3 are switched to the locked state when the first cam 2 rotates against the force acting on it by the first spring 51, and switched to the unlocked state when the second cam 3 rotates against the force acting on it by the first spring 51. The locking device 100 includes a pressing member 4 that presses the second cam 3, and a second spring 52 that applies force in the direction in which the pressing member 4 presses. The pressing member 4 is movable between the unlocked position and the locked position, and can press in such a way that the second cam 3 rotates during this period. The spring constant of the second spring 52 is greater than the spring constant of the first spring 51.

Description

Technical Field

[0001] The present invention relates to a locking device.

Background Art

[0002] Conventionally, a snatch lock mechanism has been proposed as a locking device for a door. The snatch lock mechanism is configured as described in, for example, Patent Document 1. When the door is in the closed state, the lock plate is pushed by a receiver and rotates, and the tongue piece engages with the locking groove, thereby automatically completing the locking. When unlocking, the lock plate rotates by operating the trigger lever, and the tongue piece pushes out the receiver by the force of a spring, and the door is automatically driven in the opening direction. This mechanism has advantages in terms of improving the efficiency of assembly work and reducing the number of parts.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the locking device (snatch lock mechanism) described in Patent Document 1 is applied to, for example, a front-loading and rear-unloading delivery box, the lock plate rotates when the front door is closed and locked, and the trigger lever is operated when the rear door is opened so that the lock plate can be rotated. However, in a delivery box configured in this way, unlocking is performed only by opening the rear door. For example, when a person accidentally enters a large delivery box, unlocking cannot be performed from the inside, that is, emergency unlocking is not possible, which poses a problem in terms of convenience.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a locking device that can improve convenience by enabling unlocking by a plurality of operations. [Means for solving the problem]

[0006] According to the present invention, the locking device is switchable between a locked state and an unlocked state. A first cam and a second cam, which face each other and are rotatable around their respective shafts, A first spring applies force to one end of each of the first and second cams. Equipped with, The first cam and the second cam are The first cam rotates in the first direction against the force acting on it by the first spring, switching from the unlocked state to the locked state. The locking state is switched to the unlocked state when the second cam rotates in the second direction against the force acting on it by the first spring. In a locking device, A pressing member that presses against the second cam, A second spring that applies force in the direction of the pressing member, The operating part extends from the shaft of the second cam to the other end and Equipped with, The pressing member is The unlocked position corresponds to the position of one end of the second cam in the unlocked state, It is movable between the locked position and the position of one end of the second cam in the locked state, During this time, one end of the second cam can be pressed so that the second cam rotates in the second direction. It is moved from the unlocked position to the locked position against the force acting by the second spring. The spring constant of the second spring is greater than the spring constant of the first spring. The first cam and the second cam are rotated in a second direction when an operating force is applied to the operating part that resists the force acting by the first spring.

[0007] According to this, the locking device can be switched from a locked state to an unlocked state by either an operation on the pressing member (movement) or an operation on the second cam (rotation). Specifically, when the pressing member, which has been moved to the locked position, is moved to the unlocked position, the second cam, which is in the locked state, is pressed against the pressing member by the force of the second spring. Here, the locking device can be configured such that the force of the second spring is greater than the force of the first spring. Therefore, the pressed second cam rotates in the second direction against the force of the first spring. This switches the locking device from a locked state to an unlocked state. Alternatively, even if the pressing member remains in the locked position, an operating force is applied to the operating part that resists the force of the first spring, causing the second cam to rotate in the second direction, and the locking device is similarly switched to an unlocked state. [Effects of the Invention]

[0008] According to the present invention, the convenience of the locking device can be improved by enabling unlocking through multiple operations. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view showing a delivery box to which a locking device according to an embodiment of the present invention is applied. [Figure 2] This is a perspective view showing the configuration of the delivery box. [Figure 3] This is a perspective view showing the configuration of the locking device, specifically the unlocked state. [Figure 4] This is a perspective view of the same figure, showing the locked state. [Figure 5] This is a longitudinal cross-sectional view showing the various forces acting on the locking device. [Figure 6] This is a vertical cross-sectional view showing the operation of the locking device, specifically the unlocked state. [Figure 7] This is a vertical cross-sectional view illustrating the transition from the unlocked state to the locked state. [Figure 8] This is a vertical cross-sectional view showing the locked state. [Figure 9]It is a longitudinal sectional view showing the state of being switched from the locked state to the unlocked state. [Figure 10] It is a longitudinal sectional view showing the state of being switched from the locked state to the unlocked state by manual operation. [Figure 11] It is a longitudinal sectional view showing the unlocked state.

Embodiments for Carrying out the Invention

[0010] Hereinafter, the lock device 100 according to the embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description will not be repeated. Also, in the following description, terms such as "upper", "lower", "horizontal", and "vertical" that indicate positions or directions may be used. These terms are used for convenience to facilitate understanding of the embodiment and are not limited to the positions or directions in actual implementation.

[0011] [Configuration of Delivery Box 1] First, referring to FIGS. 1 and 2, the configuration of the delivery box 1 to which the lock device 100 according to the embodiment of the present invention is applied will be described.

[0012] From FIGS. 1 and 2, the delivery box 1 has a main body 10, a front door 11 provided at the front of the main body 10, and a rear door 12 provided at the rear of the main body 10.

[0013] A front outer frame 10b is provided at the front of the main body 10, and the front door 11 is provided so as to be openable and closable with respect to the front outer frame 10b. A locking device 13 is provided on the front door 11, and a locking member 14 is connected to the locking device 13. The locking member 14 is configured to be rotatable on the rear side of the front door 11 in accordance with the rotation operation when the knob portion 13b of the locking device 13 is rotated on the front side of the front door 11. The lock device 100 is provided, for example, on the back side of the front outer frame 10b. Although details will be described later, the lock device 100 is switched from the unlocked state to the locked state when the locking device 13 is locked.

[0014] The solid line in Figure 1 represents a partially enlarged front view of the delivery box 1 when the front door 11 is closed, the locking device 13 is locked, and the locking device 100 is locked. At this time, the locking member 14 is housed in the locking device 100 and its rotation is restrained.

[0015] The dotted line in Figure 1 represents a partially enlarged front view of the delivery box 1 when the locking device 100 is unlocked. At this time, the locking member 14 is not restrained by the locking device 100 and rotates in the direction of the arrow shown, flipping up, and the knob 13b also rotates in the direction of the arrow shown. The locking member 14 is provided with a spring (not shown), and a force is applied to the locking member 14 so that it rotates in the direction of the arrow shown. As a result, the locking member 14 is kept flipped up when the front door 11 is open. When locking the locking device 13, the knob 13b rotates against the force in the direction opposite to the arrow shown, causing the locking member 14 to rotate in the direction opposite to the arrow shown.

[0016] As shown in Figure 1, a rear outer frame 10c is also provided at the rear of the main body 10, similar to the front door 11, and the rear door 12 is provided so as to be able to open and close relative to the rear outer frame 10c. As shown in Figure 2, a rod 15 extending in the front-rear direction of the main body 10 of the delivery box 1 is provided between the locking device 100 and the rear door 12. One end of the rod 15 is connected to the locking device 100 and is supported by a rod support part 16 so as to be able to slide in the front-rear direction of the main body 10 (hereinafter, the direction in which the rod 15 slides will be referred to as the "sliding direction").

[0017] The solid line in Figure 2 shows a partially enlarged cross-sectional view of the delivery box 1 when the rear door 12 is closed. At this time, the rear side of the rear door 12 (for example, the rear door frame 12b) is in contact with the end face 15b of the rod 15. As will be described in more detail later, a force is applied to the rod 15 in the direction of pushing the rear door 12 (in the direction of the arrow shown in the figure). With this force applied in the direction of pushing the rear door 12, the rear door 12 is locked by a locking device or the like (not shown) and kept in the closed state.

[0018] The dotted line in Figure 2 represents a partially enlarged cross-sectional view of the delivery box 1 when the rear door 12 is open. Because the rod 15 is subjected to the force pushing the rear door 12, the rod 15 slides a predetermined amount backward to the rear of the main body 10 in accordance with the opening of the rear door 12. In other words, the rod 15 is configured to slide in the sliding direction in conjunction with the opening and closing operation of the rear door 12. Specifically, when the rear door 12 is closed, the rod 15 slides a predetermined amount forward of the main body 10, and when the rear door 12 is opened, it slides a predetermined amount backward of the main body 10.

[0019] [Configuration of locking device 100] Next, the configuration of the locking device 100 will be described with reference to Figure 3 (locking device 100 in the unlocked state) and Figure 4 (locking device 100 in the locked state). As shown in Figures 3 and 4, the locking device 100 comprises a case 5, a lock cam 2 (an example of a first cam) and a lever cam 3 (an example of a second cam) housed in the case 5, and a tension spring 51 (an example of a first spring).

[0020] Case 5 consists of four plates 50 surrounding the lock cam 2 and the lever cam 3. The lock cam 2 and the lever cam 3 are positioned opposite each other in the sliding direction, and their respective shafts 23 and 33 are supported by two wide plates 50b, 50b of Case 5 so that they can rotate around the lock-side shaft 23 and the lever-side shaft 33, respectively.

[0021] In the following, the direction in which each cam 2, 3 rotates clockwise in the figure will be referred to as the "direction of rotation (an example of the first direction)," and the direction in which each cam 2, 3 rotates counterclockwise will be referred to as the "reverse direction of rotation (an example of the second direction)."

[0022] The tension spring 51 is hooked at both ends onto the hooking portions 28 and 35 on the ends 21 and 31 of the lock cam 2 and lever cam 3, respectively, so that the ends 21 and 31 are connected to the tension spring 51 and a force is applied to them in a direction that brings them closer together.

[0023] As will be explained in more detail later, the locking member 14 of the locking device 13 is inserted into the other ends 22 and 32 of the lock cam 2 and lever cam 3 in the downward direction shown in the figure (hereinafter referred to as the "insertion direction"), switching the locking device 100 to the locked state (see Figure 4). When the locking device 100 is switched to the unlocked state (see Figure 3), the locking member 14 can be detached from the locking device 100 in the opposite direction to the insertion direction (hereinafter referred to as the "detachment direction"). Guide grooves 56 extending in the insertion direction are provided on the two wider plates 50b, 50b of the case 5, respectively, to guide the locking member 14 along the insertion direction.

[0024] The lever cam 3 has a lever-side projection 34 on the surface facing the lock cam 2 (lever-side facing surface) that protrudes toward the lock cam 2. The lever-side projection 34 is provided on one end 31 side with respect to the lever-side shaft portion 33. The lock cam 2 has a lock-side projection 25 on the surface facing the lever cam 3 (lock-side facing surface) that protrudes toward the lever cam 3. The lock-side projection 25 is provided on one end 21 side with respect to the lock-side shaft portion 23. On the other end 22 side of the lock-side projection 25 on the lock-side facing surface, a further projection 27 is provided, and a lock-side recess 26 is formed between the two projections 25 and 27, recessing away from the lever cam 3.

[0025] When the locking device 100 is unlocked (see Figure 3), the lever-side projection 34 is positioned on the insertion side of the locking-side projection 25. On the other hand, when the locking device 100 is locked (see Figure 4), the locking-side projection 25 is positioned on the insertion side of the lever-side projection 34, and the lever-side projection 34 fits into the locking-side recess 26.

[0026] In other words, the unlocked state and the locked state are switched by a change in the position of each cam 2, 3. For the position of each cam 2, 3 to change, the lock-side projection 25 and the lever-side projection 34 must be rotated against the force acting on them by the tension spring 51 in a direction away from each other.

[0027] The lock cam 2 is provided with a receiving recess 24 on the other end 22 side of the protrusion 27 on the locking side facing surface, which accommodates the inserted locking member 14. The receiving recess 24 is formed as a recess in the direction away from the lever cam 3. The receiving recess 24 opens in the direction of release when the locking device 100 is in the unlocked state (see Figure 3), and closes in the direction of release when the locking device 100 is in the locked state (see Figure 4). As a result, when the locking device 100 is in the unlocked state, the locking member 14 can be inserted into the receiving recess 24 and the locking member 14 can be released from the receiving recess 24. On the other hand, when the locking device 100 is in the locked state, the locking member 14 housed in the receiving recess 24 is restrained in the direction of release by being unable to move in that direction.

[0028] The other end 32 of the lever cam 3 is configured to extend in the detachment direction and be exposed from the case 5, and the portion exposed from the case 5 functions as an operating part 32b. By pinching and operating the operating part 32b, an operating force is applied to the lever cam 3 by manual input. In addition, one end 31 of the lever cam 3 is configured to extend in the insertion direction to near the end of the case 5.

[0029] The locking device 100 further includes a slider 4 (an example of a pressing member) and a compression spring 52 (an example of a second spring) that press against one end 31 of the lever cam 3. The end 41 of the slider 4 is connected to the end of the rod 15, for example, through a connecting hole 44 and a connecting pin 45, so that it can slide along the direction in which the rod 15 slides (sliding direction) as described above. A slider guide hole 55 is provided in the narrow rod 15 side plate 50c of the case 5 at a position corresponding to the slider 4 and sized to match the outer shape of the slider 4. The slider 4 is slidably supported by the slider guide hole 55.

[0030] The slider 4 is a U-shaped member in cross-sectional view as shown in the figure, with its opening facing the rod 15 and its open end connected to the rod 15. In the same cross-sectional view, the slider 4 clamps one end 31 of the lever cam 3 in the axial direction of the lever-side shaft portion 33 near the other end 42, and clamps the rod 15 in the axial direction on the one end 41 side.

[0031] A pressure pin 43 is provided through the other end 42 of the slider 4 along the axial direction, and the outer surface of the pressure pin 43 is configured to contact the lever-side opposing surface of one end 31 of the lever cam 3. Pin guide holes 54 extending in the sliding direction are provided in both wide plates 50b, 50b facing each other in the axial direction in the case 5, at positions corresponding to the pressure pin 43. The pressure pin 43 is guided and supported in the pin guide holes 54 so as to be slidable in the sliding direction.

[0032] In case 5, the narrow plate 50d on the side opposite the rod 15 is provided with a spring support portion 53 that supports one end of the compression spring 52, and the compression spring 52 is positioned sandwiched between the spring support portion 53 and the outer surface of the closed end of the slider 4. As a result, a sliding force is applied to the slider 4 by the compression spring 52, and the outer surface of the pressure pin 43 can press against one end 31 of the lever cam 3. The lever cam 3, pressed by the pressure pin 43, is rotated in the reverse direction.

[0033] The slider 4 is movable between an unlocked position P1 (see Figure 3) corresponding to the position of one end 31 of the lever cam 3 in the unlocked state, and a locked position P2 (see Figure 4) corresponding to the position of one end 31 of the lever cam 3 in the locked state. During this time, the pressure pin 43 contacts one end 31 of the lever cam 3, and a force is applied by the compression spring 52.

[0034] The distance in the sliding direction between the unlocked position P1 and the locked position P2 is configured to correspond to the predetermined amount of slide of the rod 15 during the opening and closing operation of the rear door 12 as described above. That is, the slider 4 is positioned in the unlocked position when the rear door 12 is open, and the slider 4 is positioned in the locked position P2 when the rear door 12 is closed.

[0035] The slider 4 is moved from the unlocked position P1 to the locked position P2 by an action (e.g., a "set force") that resists the force acting on the compression spring 52. Here, the spring constant of the compression spring 52 is configured to be greater than the spring constant of the tension spring 51. As a result, the force acting on the lever cam 3 by the compression spring 52 is configured to be greater than the force acting on the tension spring 51. The unit of "spring constant" is, for example, [N / m] or "N / mm".

[0036] Next, referring to Figure 5, the relationship between the forces acting on each cam 2 and 3 when their positions change will be explained. To reiterate, the unlocked state and the locked state are switched by a change in the position of each cam 2 and 3. As shown in Figure 5, when the position of each cam 2 and 3 changes and the lock-side projection 25 and the lever-side projection 34 move apart from each other, a force F1 from the compression spring 52 and a force F2 from the tension spring 51 are applied to one end 31 of the lever cam 3. At this time, the spring constant of the compression spring 52 is greater than the spring constant of the tension spring 51, so that the force F1 from the compression spring 52 is greater than the force F2 from the tension spring 51.

[0037] In this embodiment, the tension spring 51 and compression spring 52 are configured to be at their natural length in the unlocked state shown in Figure 3. However, each spring 51 and 52 may be configured to bend by a predetermined amount in the unlocked state shown in Figure 3, thereby generating a force from each spring 51 and 52.

[0038] [Operation of locking device 100] Next, the operation of the locking device 100 will be described with reference to Figures 6 to 11. In Figures 6 to 11, the rod 15 is not shown. Figure 6 shows the locking device 100 in the unlocked state, with the slider 4 in the unlocked position P1 (i.e., the rear door 12 is open).

[0039] In this state, when the rear door 12 is closed, the slider 4 slides to the locked position P2 via the rod 15, as shown by the dashed line in Figure 6. At this time, the lever cam 3 is subjected to the set force F1' which resists the force acting on it by the compression spring 52.

[0040] In this state, as shown in Figure 7, when the locking member 14 is inserted in the insertion direction, the locking member 14 comes into contact with the receiving surface 24b of the housing recess 24, and the lock cam 2 rotates in the rotational direction against the force F2 acting on it by the tension spring 51, and the lock-side projection 25 and the lever-side projection 34 move apart from each other. When the lock-side projection 25 goes over the lever-side projection 34, as shown in Figure 8, the lever-side projection 34 fits into the lock-side recess 26, and the lever cam 3 rotates in the rotational direction, changing the position of each cam 2 and 3. In other words, the locking device 100 is switched from the unlocked state to the locked state. Thus, the locking device 100 can be configured so that when the rear door 12 is closed, the locking device 13 inserts the locking member 14 to switch from the unlocked state to the locked state.

[0041] As shown in Figure 9, when the setting force F1' is released and the slider 4 slides from the locked position P2 to the unlocked position P1, the pressing pin 43 of the slider 4 presses against one end 31 of the lever cam 3, causing the lever cam 3 to rotate in the reverse direction, and the lock-side projection 25 and the lever-side projection 34 to separate from each other.

[0042] In this case, as explained above with reference to Figure 5, the force F1 acting on the compression spring 52 is greater than the force F2 acting on the tension spring 51, so that as the slider 4 moves, the lever cam 3 rotates in the opposite direction against the force F2 acting on the tension spring 51. When the lever-side projection 34 passes over the lock-side projection 25, as shown in Figure 6, the lever-side projection 34 moves toward the insertion direction of the lock-side projection 25, and the lock cam 2 rotates in the opposite direction, changing the position of each cam 2 and 3. In other words, the locking device 100 is switched from the locked state to the unlocked state. As a result, when the locking device 100 is in the locked state, the rear door 12 opens, releasing the setting force F1', and the locking device 100 can be configured to switch from the locked state to the unlocked state.

[0043] Furthermore, the locking device 100 can be switched from the locked state shown in Figure 8 to the unlocked state by manually operating the operating part 32b of the lever cam 3, as shown in Figure 10. That is, when a force (for example, "operating force") is applied to the operating part 32b by manual input, which opposes the force F2 acting on the tension spring 51, the lever cam 3 rotates in the reverse direction, and the lock-side projection 25 and the lever-side projection 34 move apart from each other. When the lever-side projection 34 moves over the lock-side projection 25, as shown in Figure 11, the lever-side projection 34 moves toward the insertion direction of the lock-side projection 25, and the lock cam 2 rotates in the reverse direction, changing the position of each cam 2 and 3. In other words, the locking device 100 is switched from the locked state to the unlocked state. As a result, the locking device 100 can be configured to switch from the locked state to the unlocked state even when the rear door 12 remains closed while locked, by applying the operating force to the operating part 32b of the lever cam 3. In other words, the locking device 100 can be configured to allow emergency unlocking.

[0044] In Figure 6, even if the locking member 14 is inserted while the slider 4 is in the unlocked position P1 shown by the solid line, the locking device 100 cannot be switched to the locked state because the lever cam 3 cannot change its position as described below.

[0045] To reiterate, when the position of each cam 2,3 changes, the force F1 acting on the lever cam 3 by the compression spring 52 is configured to be greater than the force F2 acting on the tension spring 51 (see Figure 5). Therefore, even when the locking member 14 is inserted in the state shown in Figure 6 and the lock cam 2 is rotated in the rotational direction, the lever cam 3 is held down in the opposite rotational direction by the force F1 acting on it by the compression spring 52 and cannot rotate in the rotational direction (see Figure 5). In other words, since the lever cam 3 cannot change its position, the locking device 100 cannot be switched to the locked state. As a result, the locking device 100 can be configured so that it cannot be switched from the unlocked state to the locked state when the slider 4 is in the unlocked position P1, that is, when the rear door 12 is open.

[0046] The lever cam 3 has an operating portion 32b on the other end 32, flanking the lever-side shaft portion 33, and one end 31 is configured to be pressable by the slider 4. In this way, the lever cam is configured to be operable by applying force to both ends 31 and 32 centered on the lever-side shaft portion 33, which helps maintain a good weight balance around the lever-side shaft portion 33. This suppresses the occurrence of unintended vibrations, for example, caused by an imbalance in weight balance with respect to the lever-side shaft portion 33.

[0047] Referring again to Figure 1, an example of the use of the locking device 100 in the delivery box 1 with the configuration described above will be explained. First, for example, when a delivery person opens the front door 11 and places a package inside the delivery box 1 with the rear door 12 closed, the front door 11 is closed and the locking device 13 is operated, switching the locking device 100 from the unlocked state to the locked state. Then, for example, a recipient opens the rear door 12 to receive the package. At this time, when the rear door 12 is opened, the locking device 100 switches from the locked state to the unlocked state, and while the rear door 12 is open, the locking device 100 cannot be switched from the unlocked state to the locked state even if the locking device 13 of the front door 11 is operated. This prevents the locking device 100 from accidentally becoming locked when the rear door 12 is open.

[0048] Even when the rear door 12 is not open, the locking device 100 is switched from the locked state to the unlocked state when the operating force is applied to the operating unit 32b inside the delivery box 1. In other words, the delivery box 1 is configured so that the locking device 100 can be switched to the unlocked state by opening the rear door 12, and so that emergency unlocking is possible from inside the delivery box 1.

[0049] Embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the embodiments described above, and can be implemented in various forms without departing from the spirit of the invention. The drawings schematically show each component in order to facilitate understanding, and the thickness, length, number, spacing, etc. of each component shown may differ from the actual dimensions due to the convenience of drawing creation. Furthermore, the material, shape, dimensions, etc. of each component shown in the above embodiments are examples and are not particularly limited, and various modifications are possible without substantially departing from the configuration of the present invention. [Explanation of Symbols]

[0050] 1. Delivery box 11 Front door 12 Rear door 13 Locking device 14 Locking component 15 rods 2. Lock cam (first cam) 21 One end (first cam) 22 Other end (first cam) 23 Locking side shaft 24 Receiving recess 25 Protrusion on the locking side 26 Lock side recess 3. Lever cam (second cam) 31 One end (second cam) 32 Other end (second cam) 33 Lever-side shaft 34. Lever-side protrusion 4. Slider (pressing member) 5 cases 51. Tension spring 52 Compression spring 100 Locking device

Claims

1. It is possible to switch between the locked and unlocked states. A first cam and a second cam, facing each other and rotatable around their respective shafts, A first spring applies force to one end of each of the first and second cams. Equipped with, The first cam and the second cam are The first cam is rotated in the first direction against the force acting on the first spring, thereby switching from the unlocked state to the locked state. The locking state is switched to the unlocked state when the second cam rotates in the second direction against the force acting on it by the first spring. In a locking device, A pressing member that presses against the second cam, A second spring that applies force in the direction of the pressing member, The operating part extends from the shaft of the second cam to the other end and Equipped with, The pressing member is The unlocked position corresponds to the position of one end of the second cam in the unlocked state, It is movable between the locked position and the position of one end of the second cam in the locked state, During this time, one end of the second cam can be pressed so that the second cam rotates in the second direction. It is moved from the unlocked position to the locked position against the force acting by the second spring. The spring constant of the second spring is greater than the spring constant of the first spring. A locking device characterized in that the first cam and the second cam are rotated in a second direction when an operating force is applied to the operating part that resists the force acting by the first spring.

2. The first cam and the second cam have locking members inserted into their respective other ends. The first cam has a receiving recess on its other end for accommodating the inserted locking member. The recessed area is The locking device opens in the direction opposite to the insertion direction of the locking member when unlocked, The locking device according to claim 1, characterized in that the locking device closes in the opposite direction when locked.

3. This is used in a delivery box having a front door, a locking device provided on the front door, a locking member connected to the locking device, a rear door, and a rod positioned between the rear door and the locking device. The pressing member is When the rear door is closed, a setting force is applied via the rod to counteract the force acting on the second spring, causing it to move from the unlocked position to the locked position. When the rear door is opened, the setting force is released, and it moves from the locked position to the unlocked position. The first cam is, The locking device according to claim 2, characterized in that when the rear door is closed, the locking device is locked, the locking member is housed in the housing recess, and the first cam is rotated in the first direction.

Images