A folding mechanism for a handcart, and a handcart equipped therewith.

Abstract

To provide a folding mechanism for a handcart that allows for easy and reliable switching between an unfolded and folded state. [Solution] The folding mechanism 200 is rotatably disposed with respect to the vertical frame 20 and consists of a locking member 202 having a pivoting pin insertion hole 216 that serves as the pivoting center and a locking pin engagement groove 220, a locking pin 218 that engages with the locking pin engagement groove 220, a biasing member locking pin 124, and a locking biasing member 204 with one end connected to the locking member 202 and the other end connected to the biasing member locking pin 124. When the locking member 202 rotates, the locking biasing member 204 is positioned between the pivoting pin insertion hole 216 and the locking pin engagement groove 220, switching between a state where the locking pin engagement groove 220 can engage with the locking pin 218 and a state where the locking biasing member 204 is positioned on the opposite side of the locking pin engagement groove 220 when viewed from the pivoting pin insertion hole 216.

Description

Technical Field

[0001] The present invention relates to a folding mechanism used by users such as the elderly instead of a cane or for a shopping cart used for shopping or the like.

Background Art

[0002] Conventionally, a number of shopping carts used by users such as the elderly instead of a cane or for shopping have been developed (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Among such shopping carts, there are those that can be used in a deployed state that can be used by the user and a folded state that can be made compact when not in use, but there has been a demand for a shopping cart that can surely perform this switching with a simple operation.

[0005] The present invention has been made in view of such a situation, and an object thereof is to provide a folding mechanism for a shopping cart that can surely perform a deployed state and a folded state with a simple operation, and a shopping cart provided with the same.

Means for Solving the Problems

[0006] According to one aspect of the present invention, a pair of front frames to which a pair of front wheels are attached, a pair of rear frames to which a pair of rear wheels are attached, <​​A locking member is rotatably disposed with respect to the aforementioned vertical frame and is configured with a pivot pin insertion hole and a lock pin engagement groove that serve as the pivot center, A lock pin protruding from the rear frame and engaging with the lock pin engagement groove, A biasing member locking pin protruding from the rear frame, The locking biasing member comprises one end of which is connected to the locking member at a position different from the rotation pin insertion hole, and the other end of which is connected to the biasing member locking pin. As the locking member rotates, The lock biasing member is positioned between the rotation pin insertion hole and the lock pin engagement groove, so that the lock pin engagement groove can engage with the lock pin. The lock biasing member is characterized by switching between a state where it is positioned on the opposite side of the lock pin engagement groove when viewed from the rotation pin insertion hole. A folding mechanism is provided.

[0007] Preferably, The locking member further has a locking pin contact surface that, upon receiving a pressing force from the locking pin, rotates the locking member in a direction opposite to the rotational direction caused by the biasing force from the locking biasing member.

[0008] Preferably, The locking member is The lock biasing member, when positioned on the opposite side of the lock pin engagement groove as viewed from the rotation pin insertion hole, contacts the vertical frame and acts as a first stopper to stop the rotation of the lock member, and The lock biasing member further has a second stopper that contacts the vertical frame when the lock biasing member is positioned between the rotation pin insertion hole and the lock pin engagement groove, thereby stopping the rotation of the lock member.

[0009] Preferably, The aforementioned handcart further comprises a link frame disposed between the lower end of the vertical frame and the rear frame, The aforementioned link frame is A first link frame, one end of which is rotatably connected to the front frame and the other end of which is rotatably connected to the lower end of the vertical frame, The system includes a second link frame, one end of which is rotatably connected to the rear frame, and the other end of which is rotatably connected to the lower end of the vertical frame coaxially with the first link frame. The pivot pin insertion hole, which is the pivot center of the locking member, is located at the lower end of the vertical frame, coaxially with the first link frame and the second link frame.

[0010] According to another aspect of the present invention, A pair of front frames to which a pair of front wheels are attached, A pair of rear frames to which a pair of rear wheels are attached, A pair of vertical frames rising from above, A handcart equipped with the folding mechanism described above is provided. [Effects of the Invention]

[0011] The folding mechanism of the handcart according to the present invention is configured such that, by rotating the locking member, the locking biasing member is positioned between the rotating pin insertion hole and the locking pin engagement groove, allowing the locking pin engagement groove to engage with the locking pin, and the locking biasing member is positioned on the opposite side of the locking pin engagement groove when viewed from the rotating pin insertion hole. Therefore, by rotating the locking member and selecting either state, the handcart can be switched between an unfolded state and a folded state.

[0012] Thus, the folding mechanism for a handcart according to the present invention provides a folding mechanism for a handcart that can be reliably changed between an unfolded state and a folded state with simple operation. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view showing an example of a handcart 10 to which the present invention is applied. [Figure 2] It is a perspective view showing a state where a bag A is attached to a handcart 10 to which the present invention is applied. [Figure 3] It is a right side view showing an example of a handcart 10 to which the present invention is applied. [Figure 4] It is a perspective view showing a brake fixing device 112 in a folded state. [Figure 5] It is a perspective view showing a brake fixing device 112 in an unfolded state. [Figure 6] It is a perspective view showing a brake fixing device 112 in a folded state attached to a brake lever 102. [Figure 7] It is a perspective view showing a brake fixing device 112 in an unfolded state attached to a brake lever 102 and a handle 38. [Figure 8] It is a perspective view showing a state where a user pulls a tension part 150 and locks a locking part 148 to a handle 38. [Figure 9] It is a right side view showing an example of a folding mechanism 200. [Figure 10] It is a perspective view looking down from the right side showing an example of a folding mechanism 200. [Figure 11] It is a right side view showing an example of a folding mechanism 200 in a state where the lock is released. [Figure 12] It is a perspective view looking down from the right side showing an example of a folding mechanism 200 in a state where the lock is released. [Figure 13] It is a right side view showing an example of a folding mechanism 200 in a state where a lock biasing member 204 has returned between a rotation pin insertion hole 216 and a lock pin engagement groove 220 again. [Figure 14] It is a right side view showing an example of a folding mechanism 200 when a lock member 202 returns to the state of FIG. 9 again. [Figure 15] It is a right side view showing an example of a folding mechanism 200 in a state where the handcart 10 is folded. [Figure 16] It is a right side view showing an example of a folding mechanism 200 in a state where a lock pin contact side 222 contacts a lock pin 218. [Figure 17]This is a right side view showing an example of the folding mechanism 200 in which the locking member 202 has begun to rotate against the biasing force from the locking biasing member 204. [Figure 18] This is a right side view showing the folding mechanism 200 according to modified example 1. [Figure 19] This is a right side view showing the folding mechanism 200 in modified example 1 with the lock released. [Figure 20] This is a right side view showing a modified example 1 of the folding mechanism 200, in which the tip of the return operation member 232 is in contact with the locking member 202. [Figure 21] This is a perspective view from the right rear looking down, showing the folding mechanism 200 according to modified example 1, in which the tip of the return operation member 232 is in contact with the locking member 202. [Figure 22] This is a right side view showing the folding mechanism 200 according to modified example 1, in which the lock biasing member 204 has returned to the position between the rotation pin insertion hole 216 and the lock pin engagement groove 220. [Figure 23] This is a right side view showing the folding mechanism 200 related to a modified example 1 of the handcart 10 in a folded state. [Figure 24] This is a right side view showing the folding mechanism 200 according to Modification 1, in a state where the lock pin contact surface 222 is in contact with the lock pin 218. [Figure 25] This is a right side view showing a modified example 1 of the folding mechanism 200, in which the locking member 202 has begun to rotate against the biasing force from the locking biasing member 204. [Modes for carrying out the invention]

[0014] (Regarding the configuration of the handcart 10) An embodiment relating to a handcart 10 to which the present invention is applied will be described. As shown in Figures 1 to 3, the handcart 10 generally comprises a pair of front frames 12, a pair of front wheels 14, a pair of rear frames 16, a pair of rear wheels 18, a pair of vertical frames 20, a bag attachment frame 22, a backrest frame 24, a pair of link frames 26, a bag opening / closing frame 28, a rear bag attachment frame 30, a pair of handrail members 32, a front bridging member 34, a handle 38, a brake mechanism 100, and a folding mechanism 200.

[0015] Throughout this specification, the front of the wheelbarrow 10, as viewed from the user while pushing it by hand, will be referred to as the "front" or "front side" of the wheelbarrow 10, and the rear of the wheelbarrow 10, as viewed from the user, will be referred to as the "rear" or "backside" of the wheelbarrow 10.

[0016] Each of the pair of front frames 12 has a vertical portion 40 that rises diagonally upward from front to rear on the front side of the handcart 10, and a horizontal portion 42 that extends substantially horizontally from the upper end of the vertical portion 40. The tip of the horizontal portion 42 is pivotally supported on the vertical frame 20.

[0017] Each of the pair of front wheels 14 is rotatably mounted at the lower end of the vertical portion 40 of each front frame 12. In this embodiment, the front wheels 14 are arranged as a set of two wheels and are rotatable relative to the axis of the front frame 12, allowing the wheelbarrow 10 to be steered. Of course, the number of wheels in the front wheels 14 and whether or not they are rotatable are not limited to this.

[0018] Each of the pair of rear frames 16 has a shape that rises linearly diagonally upward from rear to front at the rear of the handcart 10, and its upper end is rotatably connected to the vertical portion 40 of each front frame 12, slightly above the approximate center.

[0019] Each of the pair of rear wheels 18 is rotatably mounted at the lower end of each rear frame 16. In this embodiment, the rear wheels 18 are arranged as a set of one wheel and are not rotatable relative to the axis of the rear frame 16. Of course, the number of wheels in the rear wheels 18 and whether or not they are rotatable are not limited to this.

[0020] Each of the pair of vertical frames 20 is positioned slightly behind the wheelbarrow 10, rising slightly diagonally upward from front to rear, and its lower end is connected to the approximate center of the rear frame 16 via a link frame 26.

[0021] The bag mounting frame 22 is a frame to which bag A is attached, and is shaped by bending a pipe material into a roughly U-shape. It has a pair of front-to-back sections 44 that extend in the front-to-back direction, and a front section 46 that connects the front ends of each front-to-back section 44. The tips of the pair of front-to-back sections 44 in the bag mounting frame 22 are each pivotally supported on a pair of vertical frames 20 at a position lower than the tips of the front frame 12 described above.

[0022] Furthermore, the bag mounting frame 22 is pivotally supported at each front-to-rear portion 44 of the bag mounting frame 22, at a position slightly forward of the center, and is connected to the upper end of the vertical portion 40 of the front frame 12.

[0023] The backrest frame 24 is a frame to which the backrest portion C of bag A is attached. It is shaped by bending a pipe material into a roughly U-shape and has a pair of vertical portions 48 that extend in the vertical direction and an upper end portion 50 that connects the upper ends of each vertical portion 48. The lower ends of the pair of vertical portions 48 in the backrest frame 24 are pivotally supported slightly towards the front of the pair of front-to-back portions 44 in the bag attachment frame 22.

[0024] As described above, the link frame 26 is positioned between the lower end of the vertical frame 20 and the rear frame 16, and is a component that enables the folding operation of the handcart 10. It consists of a first link frame 52 and a second link frame 54.

[0025] The first link frame 52 is a roughly rectangular plate-like member, the tip of which is pivotally supported on the front frame 12 at a point slightly forward (downward) from the center of the vertical portion 40 of the front frame 12, and the rear end of which is pivotally supported on the vertical frame 20 at the lower end of the vertical frame 20.

[0026] The second link frame 54 is a roughly rectangular plate-like member bent into a roughly "V" shape. Its tip is pivotally supported at the lower end of the vertical frame 20 together with the rear end of the first link frame 52 described above, and its rear end is pivotally supported at slightly rear of the center of the rear frame 16, relative to the rear frame 16.

[0027] The bag opening / closing frame 28 is a frame to which the seat portion B (which also serves as the lid) of bag A is attached. By rotating the bag opening / closing frame 28 relative to the bag mounting frame 22, the seat portion B (which also serves as the lid) of bag A rotates.

[0028] The bag opening and closing frame 28 is pivotally supported at a point slightly towards the front of the central portion of the front-to-back section 44 of the bag mounting frame 22, and is attached to the bag mounting frame 22 so as to be able to be raised and lowered in the front-to-back direction.

[0029] The rear bag mounting frame 30 is a component for attaching bag A to the rear of the vertical frame 20. It is shaped like a pipe bent into a roughly U-shape and has a pair of rear sections 56 that extend to the rear and a rear end 58 that connects the ends of each rear section 56. The front ends of the pair of rear sections 56 in the rear bag mounting frame 30 are pivotally supported on the pair of vertical frames 20 at the same position as the front ends of the front frame 12 described above.

[0030] Each of the pair of handrail members 32 is a resin cover member used as a handrail or for resting the elbows of a user sitting on the seat B, and is attached to the front frame 12 so as to cover the horizontal portion 42 of the front frame 12 from above.

[0031] The front bridging member 34 is a rod-shaped member installed between a pair of front frames 12, with both ends connected to the lower part of the vertical portion 40 of the front frame 12.

[0032] The handle 38 is a member installed between the upper ends of a pair of vertical frames 20, and in the handcart 10 according to this embodiment, a soft material such as urethane is wrapped around the outside of the handle 38 to make it easier for the user to grip.

[0033] (Regarding the configuration of the brake mechanism 100) The brake mechanism 100 equipped in the handcart 10 according to this embodiment generally comprises a brake lever 102, a brake wire 104, a pair of wheel contact members 106, a biasing member 108, a bridging member 110, and a brake locking device 112.

[0034] The brake lever 102 is a component that, when operated by the user, moves a pair of wheel contact members 106 closer to or further away from the contact surface of the rear wheel 18 via a brake wire 104. In this embodiment, it is composed of a round bar-shaped member bent into a substantially U-shape.

[0035] The brake lever 102 has a pair of side sections 114 and a brake operating section 116 mounted between the upper ends of these side sections 114. The lower ends of the pair of side sections 114 are each pivotally supported on the vertical frame 20. This allows the brake operating section 116 to be moved closer to or further away from the handle 38.

[0036] In this embodiment, the outer diameter of the brake lever 102 (particularly the brake operating portion 116) is set to be smaller than the outer diameter of the handle 38.

[0037] As described above, the brake wire 104 is a component that transmits the force exerted by the user operating the brake lever 102 to bring the brake operating part 116 closer to the handle 38 to the wheel contact member 106. One end is attached to the lower end of one side portion 114 of the brake lever 102, and the other end is attached to the brake wire mounting end 118 of one of the wheel contact members 106.

[0038] When the user brings the brake operating part 116 closer to the handle 38, the brake wire attachment end 118 on one of the wheel contact members 106 is lifted upward via the brake wire 104.

[0039] Each of the pair of wheel contact members 106 is formed by bending a roughly rectangular plate into a Z-shape in cross-section, and has a brake wire mounting end 118, an intermediate portion 120, and a wheel contact portion 122.

[0040] The brake wire attachment end 118 is the part to which the other end of the brake wire 104 is attached, as described above.

[0041] The intermediate section 120 is a part that is pivotally supported relative to the rear frame 16, with a brake wire mounting end 118 formed at one end and a wheel contact portion 122 formed at the other end. As a result, the brake wire mounting end 118 and the wheel contact portion 122 rotate relative to the rear frame 16 around the intermediate section 120.

[0042] The wheel contact portion 122 is the part that approaches and separates from the ground surface of the rear wheel 18. By contacting the ground surface of the rear wheel 18 with this wheel contact portion 122, a braking force can be applied to the rear wheel 18.

[0043] The biasing member 108 is a member that biases the wheel contact portion 122 so that the wheel contact portion 122 rotates relative to the rear frame 16 in a direction that moves the wheel contact portion 122 away from the ground surface of the rear wheel 18. In this embodiment, a helical spring is used, but the biasing member 108 is not limited to this, and a material other than a helical spring may be used to construct the biasing member 108.

[0044] One end of the biasing member 108 is attached to the wheel contact portion 122 of the wheel contact member 106, and the other end is attached to a biasing member locking pin 124 that protrudes outward from slightly below the center of the rear frame 16.

[0045] The bridging member 110 is a round rod-shaped member that links the movement of one wheel contact member 106 to that of the other wheel contact member 106. In this embodiment, one end is connected to the wheel contact portion 122 of one wheel contact member 106, and the other end is connected to the wheel contact portion 122 of the other wheel contact member 106.

[0046] As a result, when the user does not operate the brake lever 102, the biasing member 108 biases the wheel contact portion 122 of one wheel contact member 106 away from the rear wheel 18, so that no braking force is applied to the rear wheel 18. Also, via the bridging member 110, the wheel contact portion 122 of the other wheel contact member 106 is also biased away from the rear wheel 18, so that no braking force is applied to the rear wheel 18. Alternatively, the bridging member 110 can be omitted, and brake wires 104 can be provided on both the left and right sides, so that the left and right wheel contact members 106 can be operated by the brake wires 104 respectively. Omitting the bridging member 110 has the advantage of providing more legroom for the user.

[0047] Then, when the user operates the brake lever 102 to bring it closer to the handle 38, the brake wire mounting end 118 of one wheel contact member 106 is pulled upward via the brake wire 104, causing the wheel contact member 106 to rotate relative to the rear frame 16, and the wheel contact portion 122 to contact the ground surface of the rear wheel 18, thereby applying braking force to the rear wheel 18. Also, via the bridging member 110, the other wheel contact member 106 rotates relative to the rear frame 16, and the wheel contact portion 122 to contact the ground surface of the rear wheel 18, thereby applying braking force to the rear wheel 18.

[0048] The brake locking device 112 is a device that allows the brake lever 102 to remain close to the handle 38 even when the user releases their hand from the brake lever 102. As shown in Figures 4 and 5, it consists of a mounting member 130, a locking member 132, and a folding biasing member 133.

[0049] The mounting member 130 is a member that is attached to the brake lever 102, and has a mounting member body 134, a brake lever gripping portion 136, and a locking member mounting groove 138.

[0050] The mounting member body 134 is a slightly curved, rectangular member, with a brake lever gripping portion 136 formed at one end and a locking member mounting groove 138 formed at the other end.

[0051] The brake lever grip portion 136 has a roughly arc-shaped cross-section, into which the brake operating portion 116 of the brake lever 102 is fitted (see Figure 6). By fitting the brake lever 102 into the brake lever grip portion 136, the mounting member 130 is prevented from easily falling off the brake lever 102.

[0052] As shown in Figure 6, a pair of positioning members 154 may be attached to the brake lever 102 so as to sandwich the mounting position of the brake locking device 112, in order to prevent the mounting position of the brake locking device 112 from shifting left or right relative to the brake lever 102.

[0053] Returning to Figures 4 and 5, the locking member mounting groove 138 is the portion into which the engaging projection 146 (described later) formed on the locking member 132 is rotatably fitted. Rotating pin insertion holes 142 are formed at both ends facing the locking member mounting groove 138, into which the rotating pins 140 are inserted.

[0054] The locking member 132 is a member that is locked to the handle 38, and has a locking member body 144, an engaging projection 146, a locking portion 148, and a tensioning portion 150.

[0055] The locking member body 144 is a slightly curved, rectangular member, with an engaging projection 146 formed at one end, a locking portion 148 formed on the inside of the other end, and a tensioning portion 150 projecting outward from the outside of the other end.

[0056] As described above, the engaging projection 146 is a portion that is rotatably fitted into the locking member mounting groove 138 formed in the mounting member body 134, and a rotating pin insertion hole (not shown) into which the rotating pin 140, which serves as the pivot point, is inserted is formed in the engaging projection 146.

[0057] The locking portion 148 is the part that locks onto the handle 38 (see Figure 7), and is formed with a curved dimension that matches the outer diameter of the handle 38.

[0058] Furthermore, as shown in Figure 4, the locking portion 148 according to this embodiment is designed to accommodate the brake lever grip portion 136 by covering its outer surface when the locking member 132 is folded in a direction that is relatively close to the mounting member 130. As a result, when the locking member 132 is folded relative to the mounting member 130 with the brake lever 102 fitted into the brake lever grip portion 136, the locking portion 148 can be folded in a way that covers the brake lever 102, resulting in a neat appearance.

[0059] The tension portion 150 is a part formed to protrude on the opposite side from the locking portion 148, and as shown in Figure 8, it has the role of allowing the user to place their fingers or the like to bring the brake lever 102 closer to the handle 38 when locking the brake fixing device 112 attached to the brake lever 102 to the handle 38.

[0060] The folding biasing member 133 is positioned at the engagement point between the mounting member 130 and the locking member 132, and has the role of biasing the locking member 132 to rotate in a direction that is relatively closer to the mounting member 130. In this embodiment, a torsion spring is used as the folding biasing member 133, but it is not limited to this.

[0061] As described above, the brake mechanism 100 of the handcart 10 according to this embodiment includes a brake locking device 112 that holds the brake lever 102 in a state where braking force is applied by moving it toward the handle 38. The brake locking device 112 is attached to the brake lever 102 and has a locking portion 148 that locks the brake lever 102 to the handle 38 when the user moves the brake lever 102 toward the handle 38.

[0062] This allows the user to pull the brake locking device 112 with one hand to move the brake lever 102 towards the handle 38, and then lock the locking part 148 of the brake locking device 112 onto the handle 38, thereby maintaining the braking state by the brake mechanism 100 and applying the parking brake to the wheelbarrow 10.

[0063] In this embodiment, the brake mechanism 100 is configured to apply braking force to the rear wheel 18, but instead, it may be configured to apply braking force to the front wheel 14, or to apply braking force to both the front wheel 14 and the rear wheel 18.

[0064] Furthermore, since the brake lever 102 is positioned in front of the handle 38 of the handcart 10, it is easier for the user to pull the brake locking device 112 to lock the locking part 148 onto the handle 38.

[0065] Furthermore, since the outer diameter of the brake lever 102 is formed to be smaller than the outer diameter of the handle 38, it is easier for the user to move the brake lever 102 towards the handle 38, and the area of ​​the locking portion 148 that engages with the handle 38 can be made larger, making it easier to engage the locking portion 148 with the handle 38.

[0066] (Regarding the configuration of the folding mechanism 200) The folding mechanism 200 equipped in the handcart 10 according to this embodiment comprises, as shown in Figure 9, a locking member 202 and a locking biasing member 204.

[0067] As shown in Figure 10, the locking member 202 includes a locking member body 206, a knob portion 208, a first stopper 210, and a second stopper 212.

[0068] The locking member body 206 is a cam-shaped plate material, and has a rotating pin insertion hole 216 formed slightly off-center from the center into which the locking member rotating pin 214 is inserted. The locking member body 206 also has a locking pin engagement groove 220 into which the locking pin 218 engages, and a locking pin contact edge 222 formed into which the locking pin 218 abuts and receives the pressing force from the locking pin 218.

[0069] The locking member rotation pin 214 is positioned to coincide with the pivot positions of the first link frame 52, the second link frame 54 of the link frame 26, and the lower end of the vertical frame 20. In other words, the locking member 202 rotates about the pivot positions of the first link frame 52, the second link frame 54 of the link frame 26, and the lower end of the vertical frame 20 (as a coaxial position).

[0070] The knob portion 208 is a part that protrudes outward from the surface of the locking member body 206, allowing the user to rotate the locking member 202 by grasping this knob portion 208.

[0071] The first stopper 210 is a portion that protrudes outward from the back surface of the locking member body 206, and when the locking member 202 rotates clockwise in the figure, it comes into contact with the lower end of the vertical frame 20 from the left side in the figure, thereby preventing the locking member 202 from rotating further clockwise.

[0072] The second stopper 212 is located at a different position from the first stopper 210 described above, and is a portion that protrudes outward from the back surface of the locking member body 206. When the locking member 202 rotates counterclockwise in the figure, it comes into contact with the lower end of the vertical frame 20 from the right side in the figure, thereby preventing the locking member 202 from rotating further counterclockwise.

[0073] The lock biasing member 204 is a member that biases the lock member 202 in a counterclockwise direction in the figure (the rotational direction in which the lock pin 218 engages with the lock pin engagement groove 220). One end of the biasing member locking pin 124 is attached to a biasing member locking pin 124 that protrudes outward from slightly below the center of the rear frame 16, and the other end is attached to the lock member 202 slightly closer to the lock pin engagement groove 220 than the rotation pin insertion hole 216 (the rotation center of the lock member 202).

[0074] (Regarding the operation of the folding mechanism 200) Next, we will explain the operation of the folding mechanism 200 that has been described so far. As shown in Figure 9, we will begin the explanation from the state in which the wheelbarrow 10 is unfolded. In the state in which the wheelbarrow 10 is unfolded, the lock pin engagement groove 220 of the lock member 202 is engaged with the lock pin 218. This prevents the wheelbarrow 10 from being folded accidentally.

[0075] In this deployed state, the lock biasing member 204 is located between the pivot pin insertion hole 216, which is the pivot center of the lock member 202, and the lock pin engagement groove 220. As a result, the lock biasing member 204 biases the lock member 202 in a direction that attempts to rotate it counterclockwise in the figure, thus maintaining the engagement between the lock pin engagement groove 220 and the lock pin 218.

[0076] To fold the handcart 10 from this state, the user first grasps the knob portion 208 of the locking member 202 and rotates the locking member 202 clockwise against the biasing force from the locking biasing member 204.

[0077] At this time, as shown in Figures 11 and 12, by rotating the locking member 202 clockwise until the locking biasing member 204 is outside the rotating pin insertion hole 216 (right side in the figure), the locking biasing member 204 switches to biasing the locking member 202 in the direction of clockwise rotation in the figure, and the state in which the locking pin 218 is disengaged from the locking pin engagement groove 220 is maintained.

[0078] Furthermore, with the lock biasing member 204 positioned outside the rotation pin insertion hole 216 (on the right side in the figure), the first stopper 210 of the lock member 202 contacts the vertical frame 20 from the left side in the figure, thereby preventing the lock member 202 from rotating further clockwise.

[0079] With the lock pin 218 disengaged from the lock pin engagement groove 220, as shown in Figure 13, when the rear frame 16 is moved towards the front frame 12 to fold the wheelbarrow 10, the angle between the direction in which the lock biasing member 204 extends and the vertical frame 20 changes, causing the first stopper 210 of the lock member 202 to be pushed by the vertical frame 20, and the lock biasing member 204 returns to the inside of the pivot pin insertion hole 216 (between the pivot pin insertion hole 216 and the lock pin engagement groove 220).

[0080] The lock biasing member 204 then rotates the lock member 202 counterclockwise in the figure. At this stage, the lock pin engagement groove 220 is separated from the lock pin 218. Therefore, as shown in Figures 10 and 14, the second stopper 212 of the lock member 202 contacts the vertical frame 20 from the right side in the figure, thereby preventing the lock member 202 from rotating further counterclockwise.

[0081] As shown in Figure 15, the folding operation of the handcart 10 is completed while the second stopper 212 of the locking member 202 remains in contact with the vertical frame 20.

[0082] Next, we will explain how the handcart 10 unfolds from its folded state. As the rear frame 16 is moved away from the front frame 12, the locking member 202 approaches the locking pin 218, and as shown in Figure 16, the locking pin contact edge 222 of the locking member 202 comes into contact with the locking pin 218.

[0083] If the rear frame 16 is moved further away from the front frame 12 from this state, the lock pin contact surface 222 is pressed by the lock pin 218, causing the lock member 202 to begin rotating clockwise in the figure against the biasing force from the lock biasing member 204, as shown in Figure 17.

[0084] Finally, the unfolding operation of the wheelbarrow 10 is completed when the lock pin 218 enters the lock pin engagement groove 220 and becomes engaged. As shown in Figure 9, the unfolded state is maintained because the lock pin engagement groove 220 remains engaged with the lock pin 218.

[0085] As described above, the folding mechanism 200 according to this embodiment allows the lock member 202 to rotate, which switches between a state where the lock biasing member 204 is positioned between the rotation pin insertion hole 216 and the lock pin engagement groove 220, allowing the lock pin engagement groove 220 to engage with the lock pin 218, and a state where the lock biasing member 204 is positioned on the opposite side of the lock pin engagement groove 220 when viewed from the rotation pin insertion hole 216. By rotating the lock member 202 and selecting either state, the wheelbarrow 10 can be switched between its unfolded and folded states. This provides a folding mechanism 200 for the wheelbarrow 10 that allows for reliable switching between the unfolded and folded states with simple operation.

[0086] (Variation 1) In the wheelbarrow 10 according to the embodiment described above, the lower end of the vertical frame 20 was connected to the rear frame 16 via the link frame 26 (first link frame 52 and second link frame 54). However, instead, the lower end of the vertical frame 20 may be connected directly and rotatably to the rear frame 16 (modification 1). Note that the brake mechanism 100 is omitted from the drawings in the following description.

[0087] In this modified example 1, the folding mechanism 200 has the configuration shown in Figure 18. Specifically, the folding mechanism 200 according to modified example 1 comprises, broadly speaking, a locking member 202, a locking biasing member 204, a locking pin 218, a locking member holding piece 230, and a return operation member 232.

[0088] In the following, only the differences between the locking member 202, the locking biasing member 204, and the locking pin 218 and the embodiments described above will be explained, and similarities will be referred to in the embodiments. Furthermore, the locking member retaining piece 230 and the return operation member 232 will be described in detail.

[0089] In the modified example 1, the locking member 202 has its pivot point set at the tip of a locking member holding piece 230 that protrudes to the rear from the lower end of the vertical frame 20. In other words, the locking member rotation pin 214 and the rotation pin insertion hole 216 are located at the tip of the locking member holding piece 230.

[0090] Furthermore, one end of the lock biasing member 204 in the modified example 1 is located in front of the locking member 202 and is attached to a biasing member locking pin 234 that protrudes from the rear frame 16.

[0091] Furthermore, the lock pin 218 protrudes from below (rearward) the biasing member locking pin 234 on the rear frame 16.

[0092] As described above, the lock member retaining piece 230 is a roughly rectangular member that protrudes from the lower end of the vertical frame 20 toward the rear, and is capable of holding the lock member 202 in a predetermined position.

[0093] The return operation member 232 is a roughly rectangular flat plate member, with one end connected to the position where the lower end of the vertical frame 20 and the rear frame 16 are connected, and as will be described later, the other end is positioned to press against the knob portion 208 of the locking member 202 when the handcart 10 is folded.

[0094] Next, we will explain the operation of the folding mechanism 200 according to the modified example 1 described so far. As shown in Figure 18, we will begin the explanation from the state in which the wheelbarrow 10 is unfolded. In the unfolded state of the wheelbarrow 10, the lock pin engagement groove 220 of the lock member 202 is engaged with the lock pin 218. This prevents the wheelbarrow 10 from being folded accidentally.

[0095] In this deployed state, the lock biasing member 204 is located between the pivot pin insertion hole 216, which is the pivot center of the lock member 202, and the lock pin engagement groove 220. As a result, the lock biasing member 204 biases the lock member 202 in a direction that attempts to rotate it clockwise in the figure, thus maintaining the engagement between the lock pin engagement groove 220 and the lock pin 218.

[0096] To fold the handcart 10 from this state, the user first grasps the knob portion 208 of the locking member 202 and rotates the locking member 202 counterclockwise against the biasing force from the locking biasing member 204.

[0097] At this time, as shown in Figure 19, when the user rotates the locking member 202 counterclockwise until the locking biasing member 204 is outside (upper side in the figure) of the rotation pin insertion hole 216, the locking biasing member 204 switches to biasing the locking member 202 in the direction of counterclockwise rotation in the figure, and the state in which the locking pin 218 is disengaged from the locking pin engagement groove 220 is maintained.

[0098] Furthermore, with the lock biasing member 204 positioned outside the rotation pin insertion hole 216 (upper side in the figure), the first stopper 210 of the lock member 202 contacts the lock member holding piece 230 from the right side in the figure, thereby preventing the lock member 202 from rotating further counterclockwise.

[0099] With the lock pin 218 disengaged from the lock pin engagement groove 220, as the rear frame 16 is moved towards the front frame 12 and the wheelbarrow 10 is folded, the tip of the return operating member 232 approaches the lock member 202. As shown in Figures 20 and 21, the lock member 202 rotates clockwise as if pushed by the return operating member 232, and as shown in Figure 22, the lock biasing member 204 returns to the inside of the rotation pin insertion hole 216 (between the rotation pin insertion hole 216 and the lock pin engagement groove 220).

[0100] The lock biasing member 204 then rotates the lock member 202 clockwise in the figure. At this stage, the lock pin engagement groove 220 is separated from the lock pin 218, so the second stopper 212 of the lock member 202 now comes into contact with the lock member holding piece 230, thereby preventing the lock member 202 from rotating any further clockwise.

[0101] In this way, the folding operation of the handcart 10 is completed while the second stopper 212 of the locking member 202 remains in contact with the locking member retaining piece 230 (Figure 23).

[0102] Next, we will explain how the handcart 10 unfolds from its folded state. As the rear frame 16 is moved away from the front frame 12, the locking member 202 approaches the locking pin 218, and as shown in Figure 24, the locking pin contact edge 222 of the locking member 202 comes into contact with the locking pin 218.

[0103] If the rear frame 16 is moved further away from the front frame 12 from this state, the lock pin contact surface 222 is pressed by the lock pin 218, causing the lock member 202 to begin rotating counterclockwise in the figure against the biasing force from the lock biasing member 204 (Figure 25).

[0104] Finally, the unfolding operation of the wheelbarrow 10 is completed when the lock pin 218 enters the lock pin engagement groove 220 and becomes engaged. As shown in Figure 18, the unfolded state is maintained because the lock pin engagement groove 220 remains engaged with the lock pin 218.

[0105] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0106] 10...Handcart, 12...Front frame, 14...Front wheel, 16...Rear frame, 18...Rear wheel, 20...Vertical frame, 22...Bag attachment frame, 24...Backrest frame, 26...Link frame, 28...Bag opening / closing frame, 30...Rear bag attachment frame, 32...Handrail member, 34...Front bridging member, 38...Handle, 40...Vertical part (of front frame 12), 42...Horizontal part (of front frame 12), 44...Front-rear part (of bag attachment frame 22), 46...Front part (of bag attachment frame 22), 48...Up-down part (of backrest frame 24), 50...Upper end (of backrest frame 24), 52...First link frame, 54...Second link frame, 56...Rear part (of rear bag attachment frame 30), 58...Rear end (of rear bag attachment frame 30) 100...Brake mechanism, 102...Brake lever, 104...Brake wire, 106...Wheel contact member, 108...Biasing member, 110...Bridge member, 112...Brake fixing device, 114...Side part (of brake lever 102), 116...Brake operating part (of brake lever 102), 118...Brake wire mounting end (of wheel contact member 106), 120...Intermediate part (of wheel contact member 106), 122...(Wheel contact member 106 124... Wheel contact portion, 130... Biasing member locking pin, 130... Mounting member (of brake fixing device 112), 132... Locking member (of brake fixing device 112), 133... Folding biasing member, 134... Mounting member body, 136... Brake lever gripping portion, 138... Locking member mounting groove, 140... Rotating pin, 142... Rotating pin insertion hole, 144... Locking member body, 146... Engaging projection, 148... Locking portion, 150... Tension portion, 154... Positioning member 200...Folding mechanism, 202...Locking member, 204...Locking biasing member, 206...Locking member body, 208...Knob part, 210...First stopper, 212...Second stopper, 214...Locking member rotation pin, 216...Rotation pin insertion hole, 218...Locking pin, 220...Locking pin engagement groove, 222...Locking pin contact edge, 230...Locking member holding piece, 232...Return operation member, 234...Biasing member locking pin A...Bag, B...Seat, C...Backrest

Claims

1. A pair of front frames to which a pair of front wheels are attached, A pair of rear frames to which a pair of rear wheels are attached, A folding mechanism used in a handcart, comprising a pair of vertical frames that rise upward, A locking member is rotatably disposed with respect to the aforementioned vertical frame and is configured with a pivot pin insertion hole and a lock pin engagement groove that serve as the pivot center, A lock pin protruding from the rear frame and engaging with the lock pin engagement groove, A biasing member locking pin protruding from the rear frame, The locking biasing member comprises one end of which is connected to the locking member at a position different from the rotation pin insertion hole, and the other end of which is connected to the biasing member locking pin. As the locking member rotates, The lock biasing member is positioned between the rotation pin insertion hole and the lock pin engagement groove, so that the lock pin engagement groove can engage with the lock pin. The lock biasing member is characterized by switching between a state where it is positioned on the opposite side of the lock pin engagement groove when viewed from the rotation pin insertion hole. Folding mechanism.

2. The locking member further has a locking pin contact surface that, upon receiving a pressing force from the locking pin, rotates the locking member in a direction opposite to the rotational direction caused by the biasing force from the locking biasing member. The folding mechanism according to claim 1.

3. The locking member is The lock biasing member, when positioned on the opposite side of the lock pin engagement groove as viewed from the rotation pin insertion hole, contacts the vertical frame and acts as a first stopper to stop the rotation of the lock member, and The lock biasing member further has a second stopper that contacts the vertical frame when the lock biasing member is positioned between the rotation pin insertion hole and the lock pin engagement groove, thereby stopping the rotation of the lock member. The folding mechanism according to claim 1.

4. The aforementioned handcart further comprises a link frame disposed between the lower end of the vertical frame and the rear frame, The aforementioned link frame is A first link frame, one end of which is rotatably connected to the front frame and the other end of which is rotatably connected to the lower end of the vertical frame, The system includes a second link frame, one end of which is rotatably connected to the rear frame, and the other end of which is rotatably connected to the lower end of the vertical frame coaxially with the first link frame. The pivot pin insertion hole, which is the pivot center of the locking member, is located at the lower end of the vertical frame, coaxially with the first link frame and the second link frame. The folding mechanism according to claim 1.

5. A pair of front frames to which a pair of front wheels are attached, A pair of rear frames to which a pair of rear wheels are attached, A pair of vertical frames rising from above, A folding mechanism according to any one of claims 1 to 4 is provided. Wheelbarrow.

Images