Hand-pushed transport cart

Abstract

To provide a technique which can improve convenience of a user.SOLUTION: A hand cart comprises: an engine; a clutch mechanism which can switch between transmission state and nontransmission state; a differential mechanism distributing power from the engine into a first grounding part and a second grounding part in which the differential mechanism can be switchable between a non-lock state and a lock state; a changeover part; and an operation part. The changeover part can switch the state of the clutch mechanism, according to a first operation of a user for the operation part, between the transmission state of the clutch mechanism and the nontransmission state without changing the state of the differential mechanism, and can switch the state of the differential mechanism, according to a second operation of a user for the operation part, between the non-lock state of the differential mechanism and the lock state without changing the state of the clutch mechanism.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a push cart. [Background technology]

[0002] Patent Document 1 discloses a wheel steering device including a prime mover, first and second ground contact portions, a clutch mechanism switchable between a transmission state in which power from the prime mover is transmitted to the first and second ground contact portions and a non-transmission state in which power from the prime mover is not transmitted to the first and second ground contact portions, a differential mechanism that distributes power from the prime mover to the first and second ground contact portions and is switchable between an unlocked state in which a rotational difference is permitted to occur between the first and second ground contact portions and a locked state in which a rotational difference is prohibited to occur between the first and second ground contact portions, a switching unit, and an operating unit. The switching unit is capable of simultaneously switching between the state of the differential mechanism and the state of the clutch mechanism in response to a user's operation of the operating unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 62-31575 Summary of the Invention [Problem to be solved by the invention]

[0004] The wheel steering device of Patent Document 1 is configured to be able to realize only two states: a state in which the clutch mechanism is in a transmission state and the differential mechanism is in a non-locked state, and a state in which the clutch mechanism is in a non-transmission state and the differential mechanism is in a locked state. For example, the wheel steering device of Patent Document 1 cannot realize a state in which the clutch mechanism is in a transmission state and the differential mechanism is in a locked state. In this case, for example, when only one of the first and second grounding portions is in contact with the ground, it becomes difficult to transmit power from the prime mover to the grounding portion that is in contact with the ground, which causes inconvenience to the user.

[0005] This specification provides a technology that can improve user convenience. [Means for solving the problem]

[0006] The pushcart disclosed in this specification may include a prime mover, first and second ground contact portions driven by the prime mover, a clutch mechanism switchable to one of a transmission state in which power from the prime mover is transmitted to the first and second ground contact portions and a non-transmission state in which power from the prime mover is not transmitted to the first and second ground contact portions, a differential mechanism that distributes power from the prime mover to the first and second ground contact portions, the differential mechanism being switchable to one of a non-locked state in which a rotational difference is allowed to occur between the first and second ground contact portions and a locked state in which the rotational difference is prohibited from occurring between the first and second ground contact portions, a switching unit for switching the state of the clutch mechanism and the state of the differential mechanism, and an operating unit. The switching unit may be capable of switching the state of the clutch mechanism between the transmitted state and the non-transmitted state in response to a first operation of the user on the operating unit, without switching the state of the differential mechanism, and may be capable of switching the state of the differential mechanism between the non-locked state and the locked state in response to a second operation of the user on the operating unit, without switching the state of the clutch mechanism.

[0007] According to the above configuration, by performing a first operation on the operating unit, the user can switch the state of the clutch mechanism between a transmission state and a non-transmission state without switching the state of the differential mechanism. Furthermore, by performing a second operation on the operating unit, the user can switch the state of the differential mechanism between a non-lock state and a locked state without switching the state of the clutch mechanism. According to this configuration, the switching unit can realize three states: a state in which the differential mechanism is in the non-lock state and the clutch mechanism is in the transmission state; a state in which the differential mechanism is in the non-lock state and the clutch mechanism is in the non-transmission state; and a state in which the differential mechanism is in the lock state and the clutch mechanism is in the transmission state. This improves user convenience.

[0008] Another pushcart disclosed in this specification may include a prime mover, first and second ground contact portions driven by the prime mover, a clutch mechanism switchable to one of a transmission state in which power from the prime mover is transmitted to the first and second ground contact portions and a non-transmission state in which power from the prime mover is not transmitted to the first and second ground contact portions, a differential mechanism that distributes power from the prime mover to the first and second ground contact portions, the differential mechanism being switchable to one of a non-locked state in which a rotational difference is allowed to occur between the first and second ground contact portions and a locked state in which the rotational difference is prohibited from occurring between the first and second ground contact portions, a switching unit for switching the state of the clutch mechanism and the state of the differential mechanism, and an operating unit. The switching unit may be movable to one of a first position in which the differential mechanism is in the unlocked state and the clutch mechanism is in the transmitted state, a second position in which the differential mechanism is in the unlocked state and the clutch mechanism is in the non-transmitted state, and a third position in which the differential mechanism is in the locked state and the clutch mechanism is in the transmitted state, in response to a user's operation of the operating unit.

[0009] According to the above configuration, the switching unit can be moved to any one of the first position, the second position, and the third position in response to a user's operation of the operating unit. The switching unit then realizes three states: a state in which the differential mechanism is in an unlocked state and the clutch mechanism is in a transmitted state; a state in which the differential mechanism is in an unlocked state and the clutch mechanism is in a disengaged state; and a state in which the differential mechanism is in a locked state and the clutch mechanism is in a transmitted state. This improves user convenience. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a perspective view of a push cart 2 according to an embodiment, seen from above on the front right. [Figure 2] FIG. 2 is a diagram showing a control configuration of the hand truck 2 according to the embodiment. [Figure 3] 1 is a perspective view of the operation unit 38 seen from above and rear left in the embodiment, with the operation lever 52 in a state where it is located at a first operation position. [Figure 4] 1 is a perspective view of the operation unit 38 seen from above and front left in the embodiment, with the operation lever 52 in a state where it is located at a second operation position. [Figure 5] 10 is a perspective view of the operation unit 38 seen from above and rear left in the embodiment, with the operation lever 52 in a state where it is located at a third operation position. FIG. [Figure 6] FIG. 2 is a top view of the front wheel unit 16 according to the embodiment. [Figure 7] 1 is a cross-sectional view of the motor 106 and the gearbox 108 in the embodiment when the clutch mechanism 144 is in a transmission state and the differential mechanism 146 is in an unlocked state. [Figure 8] 1 is a perspective view of the front wheel unit 16 seen from above and rear right in the embodiment with the cover 111 removed and the switching unit 110 positioned at the first switching position. [Figure 9] FIG. 2 is a perspective view of the switching unit 110 in the embodiment, seen from the upper rear right. [Figure 10] 10 is a perspective view of a second base plate 180 in the embodiment as viewed from above, rear right. FIG. [Figure 11] 10 is a cross-sectional view of a switching unit 110 in the embodiment as viewed from the right. FIG. [Figure 12] 10 is a perspective view of a clutch switching unit 182 according to the embodiment, seen from above and rear right. FIG. [Figure 13] 10 is a bottom view of a first rotating part 202 of the clutch switching unit 182 according to the embodiment, as viewed from below. FIG. [Figure 14] 10 is a perspective view of a differential lock switching unit 184 according to an embodiment, as viewed from above and rear right. FIG. [Figure 15] 10 is a bottom view of a second rotating portion 232 of the differential lock switching unit 184 according to the embodiment, as viewed from below. FIG. [Figure 16] 10 is a perspective view of the switching unit 110 positioned at the second switching position, as viewed from above and rear right in the embodiment. FIG. [Figure 17] 1 is a cross-sectional view of the motor 106 and the gearbox 108 in an embodiment in which the clutch mechanism 144 is in a non-transmitting state and the differential mechanism 146 is in an unlocked state. [Figure 18] 10 is a perspective view of the switching unit 110 in the embodiment, when it is positioned at the third switching position, as viewed from above and rear right. FIG. [Figure 19] 1 is a cross-sectional view of the motor 106 and the gearbox 108 in the embodiment when the clutch mechanism 144 is in a transmission state and the differential mechanism 146 is in a locked state. [Figure 20] FIG. 10 is a schematic diagram of a switching unit 410 in a fourth modified example. DETAILED DESCRIPTION OF THE INVENTION

[0011] Representative, non-limiting embodiments of the present invention are described in detail below with reference to the drawings. This detailed description is intended simply to provide those skilled in the art with details for implementing preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Additionally, additional features and inventions disclosed below can be used separately or in conjunction with other features and inventions to provide further improved hand trucks, methods of making and using the same.

[0012] Furthermore, the combinations of features and steps disclosed in the following detailed description are not essential to practicing the invention in its broadest sense, but are described solely to specifically illustrate exemplary embodiments of the invention. Furthermore, the various features of the exemplary embodiments described above and below, and those described in the independent and dependent claims, do not necessarily have to be combined in the exact embodiments described herein, or in the exact order listed, to provide additional and useful embodiments of the invention.

[0013] All features described in this specification and / or claims are intended to be disclosed individually and independently of one another as limitations on the original disclosure and claimed particulars, apart from any configuration of features described in the examples and / or claims. Furthermore, all numerical ranges and group or aggregation descriptions are intended to disclose intermediate configurations thereof as limitations on the original disclosure and claimed particulars.

[0014] In one or more embodiments, a pushcart may include a prime mover, first and second ground contact portions driven by the prime mover, a clutch mechanism switchable to one of a transmission state in which power from the prime mover is transmitted to the first and second ground contact portions and a non-transmission state in which power from the prime mover is not transmitted to the first and second ground contact portions, a differential mechanism that distributes power from the prime mover to the first and second ground contact portions, the differential mechanism being switchable to one of an unlocked state in which a rotational difference is permitted to occur between the first and second ground contact portions and a locked state in which the rotational difference is prohibited from occurring between the first and second ground contact portions, a switching unit for switching the state of the clutch mechanism and the state of the differential mechanism, and an operating unit. The switching unit may be capable of switching the state of the clutch mechanism between the transmitted state and the non-transmitted state in response to a first operation of the user on the operating unit, without switching the state of the differential mechanism, and may be capable of switching the state of the clutch mechanism and switching the state of the differential mechanism between the non-locked state and the locked state in response to a second operation of the user on the operating unit.

[0015] In one or more embodiments, a pushcart may include a prime mover, first and second ground contact portions driven by the prime mover, a clutch mechanism switchable to one of a transmission state in which power from the prime mover is transmitted to the first and second ground contact portions and a non-transmission state in which power from the prime mover is not transmitted to the first and second ground contact portions, a differential mechanism that distributes power from the prime mover to the first and second ground contact portions, the differential mechanism being switchable to one of an unlocked state in which a rotational difference is permitted to occur between the first and second ground contact portions and a locked state in which the rotational difference is prohibited from occurring between the first and second ground contact portions, a switching unit for switching the state of the clutch mechanism and the state of the differential mechanism, and an operating unit. The switching unit is movable to one of the following positions in response to a user's operation of the operating unit: a first position in which the differential mechanism is in the unlocked state and the clutch mechanism is in the transmitted state; a second position in which the differential mechanism is in the unlocked state and the clutch mechanism is in the non-transmitted state; and a third position in which the differential mechanism is in the locked state and the clutch mechanism is in the transmitted state.

[0016] In one or more embodiments, the state of the clutch mechanism and / or the state of the differential mechanism may be switched by moving the switching portion along the first direction.

[0017] According to the above configuration, the configuration of the switching unit can be simplified compared to a configuration in which the state of the clutch mechanism and / or the state of the differential mechanism is switched by the switching unit moving in multiple directions.

[0018] In one or more embodiments, the stroller may further include a handle that can be gripped by a user, and the control may be located on the handle.

[0019] According to the above configuration, the user can easily operate the operation unit, thereby further improving user convenience.

[0020] In one or more embodiments, the switching element may be provided with a position indicator that indicates the position of the switching element relative to the clutch mechanism and the differential mechanism.

[0021] According to the above configuration, the user can understand the state of the differential mechanism and the state of the clutch mechanism by checking the position of the switching unit indicated by the position display unit, thereby further improving user convenience.

[0022] (Example) As shown in FIG. 1 , the hand truck 2 includes a chassis unit 4 and a loading platform unit 6. The loading platform unit 6 includes a bucket 300 and a loading platform frame 302 extending in the front-to-rear direction. In the loading platform unit 6, the loading platform frame 302 is fixed to the chassis unit 4 with screws. In the loading platform unit 6, the bucket 300 is not fixed to the loading platform frame 302, and a user can place the bucket 300 on the loading platform frame 302 or lift the bucket 300 and remove it from the loading platform frame 302. A user can load soil, fertilizer, etc. into the bucket 300 and transport it.

[0023] (Chassis Unit 4 Configuration) The chassis unit 4 includes a handle unit 10, a battery box 12, a chassis frame 14, a front wheel unit 16, and a rear wheel unit 18.

[0024] (Configuration of battery box 12) The battery box 12 is fixed to the handle unit 10. The battery box 12 houses a battery pack 12a (see FIG. 2) and a control device 12b (see FIG. 2). The control device 12b (see FIG. 2) controls the operation of a motor 106 (see FIG. 2), which will be described later. The battery box 12 is provided with a remaining charge display unit (not shown) that displays the remaining charge of the battery pack 12a (see FIG. 2), etc.

[0025] (Configuration of handle unit 10) The handle unit 10 includes a handle base 20, a right handle 22, and a left handle 24. The right handle 22 and the left handle 24 are screwed to the handle base 20. The handle base 20 is screwed to the chassis frame 14. The battery box 12 is screwed to the handle base 20.

[0026] The right handle 22 includes a right pipe 30, a right grip 32, a switch box 34, a drive lever 36, and an operation unit 38. The right pipe 30 includes a right support portion 30a that extends vertically, and a right handle portion 30b that bends rearward from the upper end of the right support portion 30a. The right grip 32, switch box 34, and operation unit 38 are attached to the right handle portion 30b of the right pipe 30. The right grip 32 is provided behind the switch box 34. The switch box 34 is provided behind the operation unit 38.

[0027] The switch box 34 includes a switch casing 40 and an operation panel 42. The operation panel 42 is provided on the upper surface of the switch casing 40. The operation panel 42 is provided with a plurality of switches (for example, a main power switch 42a (see FIG. 2), a forward / reverse selector switch 42b (see FIG. 2), and a speed selector switch 42c (see FIG. 2)). The drive lever 36 is attached to the rear of the switch casing 40. The switch box 34 houses a drive switch 44 (see FIG. 2) that detects when the drive lever 36 is pulled up. When the control device 12b receives a signal from the drive switch 44 (see FIG. 2) indicating that the drive lever 36 has been pulled up, the control device 12b drives a motor 106 (see FIG. 2), which will be described later.

[0028] As shown in Fig. 3, the operation unit 38 includes an operation casing 50, an operation lever 52, and a first operation cable holding portion 54. A right-side holding portion 56 and a left-side holding portion 58 that hold the operation lever 52 are provided on the top surface 50a of the operation casing 50. When viewed from the left, the right-side holding portion 56 and the left-side holding portion 58 have semicircular shapes that protrude upward. The left-side holding portion 58 is provided with an intermediate notch 58a extending leftward from the right end of the left-side holding portion 58, a rear notch 58b disposed rearward of the intermediate notch 58a, and a front notch 58c disposed frontward of the intermediate notch 58a (see Fig. 4).

[0029] The operating lever 52 is supported by the operation casing 50 (more specifically, the right-side holding portion 56 and the left-side holding portion 58) so as to be rotatable about a rotation axis (not shown) extending in the left-right direction. The operating lever 52 includes a grip portion 60 and a lock unit 62. The lock unit 62 includes a lock button 62a that is pressed by the user, and a fitting portion 62b that extends downward from the lock button 62a and has a shape that can fit into the middle notch 58a, rear notch 58b, and front notch 58c (see FIG. 4) of the left-side holding portion 58. The lock button 62a and the fitting portion 62b are integrally formed. The lock button 62a and the fitting portion 62b are biased leftward with respect to the operation casing 50 by a compression spring (not shown).

[0030] An operation cable 64 is connected to the first operation cable holding portion 54. The operation cable 64 includes a first inner cable 64a and a first outer cable 64b that covers the periphery of the first inner cable 64a. An end of the first inner cable 64a is connected to an end of the operation lever 52 at a position offset from the rotation axis (not shown) inside the operation casing 50. An end of the first outer cable 64b is held by the first operation cable holding portion 54. When the lock button 62a is not pressed by the user, the fitting portion 62b of the lock unit 62 is fitted into the intermediate notch 58a of the operation casing 50. In this state, rotation of the operation lever 52 relative to the operation casing 50 is restricted. When the lock button 62a is pressed by the user, the fitting portion 62b moves rightward and outward from the intermediate notch 58a. In this state, the user can rotate the operation lever 52 in the forward / backward direction relative to the operation casing 50. Hereinafter, the position of the operation lever 52 when the fitting portion 62b of the operation lever 52 is fitted into the intermediate notch 58a will be referred to as the "first operation position." As shown in FIG. 5, when the user operates the operation lever 52 rearward from the first operation position and releases his / her finger from the lock button 62a, the fitting portion 62b fits into the rear notch 58b. In this case, the first inner cable 64a of the operation cable 64 moves forward relative to the first outer cable 64b. Also, as shown in FIG. 4, when the user operates the operation lever 52 forward from the first operation position and releases his / her finger from the lock button 62a, the fitting portion 62b fits into the front notch 58c. In this case, the first inner cable 64a of the operation cable 64 moves rearward relative to the first outer cable 64b. Hereinafter, the position of the operating lever 52 in FIG. 5 and the position of the operating lever 52 in FIG. 4 will be referred to as the "second operating position" and the "third operating position", respectively.

[0031] As shown in FIG. 1 , the left handle 24 includes a left pipe 70, a left grip 72, a brake casing 74, and a brake lever 76. The left pipe 70 includes a left support portion (not shown) that extends vertically, and a left handle portion 70b that bends rearward from the upper end of the left support portion. The left grip 72 and the brake casing 74 are attached to the left handle portion 70b. The left grip 72 is provided rearward of the brake casing 74. A brake lever 76 is attached to the rear portion of the brake casing 74. A brake cable holder 78 is provided in front of the brake casing 74. A brake cable 80 is connected to the brake cable holder 78. The brake cable 80 includes a second inner cable 80a and a second outer cable 80b that surrounds the second inner cable 80a. An end of the second inner cable 80a is connected to the brake cable 80. An end of the second outer cable 80b is held by a brake cable holding portion 78. When the user pulls up the brake lever 76, a brake unit 104 (see FIG. 6) described below applies brakes to a right front wheel 100 and a left front wheel 102 (described below).

[0032] (Configuration of rear wheel unit 18) The rear wheel unit 18 includes a first base plate 90, a right rear wheel 92, and a left rear wheel (not shown). The right rear wheel 92 and the left rear wheel are driven wheels. The right rear wheel 92 is rotatably supported at the right end of the first base plate 90, and the left rear wheel is rotatably supported at the left end.

[0033] (Configuration of front wheel unit 16) As shown in FIG. 6, the front wheel unit 16 includes a right front wheel 100, a left front wheel 102, a brake unit 104, a motor 106, a gearbox 108, a switching unit 110, and a cover 111. The gearbox 108 includes a right gear case 112 and a left gear case 114. A right drive shaft 118 (see FIG. 7) extending within the right gear case 112 is connected to the right front wheel 100 via a right hub 116. A left drive shaft 122 (see FIG. 7) extending within the left gear case 114 is connected to the left front wheel 102 via a left hub 120. A first protrusion 124 protruding upward and an extension 126 extending leftward from the left end of the first protrusion 124 are provided on the upper surface of the rear of the gearbox 108. A second operation cable holding portion 128 that holds an end of the first outer cable 64b of the operation cable 64 is provided at the left end 126a of the extension portion 126. The brake unit 104 is connected to the left gear case 114. The brake unit 104 is a so-called disc brake. The cover 111 is screwed to the left gear case 114, and covers a part of the switching unit 110 from above.

[0034] (Motor 106) As shown in FIG. 7, the motor 106 includes a stator 130, a rotor 132, and a motor case 134. The motor 106 is, for example, a brushless DC motor. The stator 130 and the rotor 132 are housed in the motor case 134. The stator 130 is fixed to the motor case 134. The rotor 132 is fixed to a motor shaft 136. The motor shaft 136 extends in the left-right direction and is rotatably held in the motor case 134. A first spur gear 136a is fixed to the motor shaft 136. The motor 106 is electrically connected to the battery box 12 (see FIG. 2) via a power cable (not shown). Power is supplied to the motor 106 from the battery pack 12a (see FIG. 2). The operation of the motor 106 is controlled by a control device 12b (see FIG. 2).

[0035] (Gearbox 108) The gearbox 108 includes a first intermediate shaft 140, a second intermediate shaft 142, a clutch mechanism 144, and a differential mechanism 146. The first intermediate shaft 140 extends in the left-right direction and is rotatably held by the gearbox 108. The first intermediate shaft 140 includes a first gear 150 and a second spur gear 152. The first gear 150 and the second spur gear 152 are fixed to the first intermediate shaft 140. The first gear 150 meshes with a first spur gear 136a fixed to the motor shaft 136. The second intermediate shaft 142 extends in the left-right direction and is rotatably held by the gearbox 108. The second intermediate shaft 142 includes a second gear 154. The second gear 154 is immovable in the left-right direction relative to the second intermediate shaft 142 but is rotatably held. The second gear 154 has a first engagement protrusion 154a that protrudes leftward from the left end of the second gear 154. The clutch mechanism 144 has a first dog clutch 156 that is slidable in the left-right direction relative to the second intermediate shaft 142 and is held by the second intermediate shaft 142 so as to rotate integrally with the second intermediate shaft 142. The first dog clutch 156 is recessed leftward from its right end and has a first engagement recess 156a with which the first engagement protrusion 154a of the second gear 154 can engage. A first compression spring 158 is provided between the first dog clutch 156 and the left gear case 114. The first compression spring 158 biases the first dog clutch 156 rightward relative to the left gear case 114 (i.e., in a direction toward the second gear 154). The first dog clutch 156 is slidably moved in the left-right direction relative to the second intermediate shaft 142 by a clutch switching unit 182 (see FIG. 8), which will be described later. The left end of the second intermediate shaft 142 protrudes outside the left gear case 114 and is connected to the brake unit 104. The brake unit 104 brakes the rotation of the second intermediate shaft 142.

[0036] The differential mechanism 146 includes a ring gear 146a, a pinion case 146b, a pinion shaft 146c, a pinion gear 146d, a right drive gear 146e, and a left drive gear 146f. The ring gear 146a meshes with the second gear 154 of the second intermediate shaft 142. The ring gear 146a is provided with a second engagement protrusion 146g that protrudes leftward from the left end of the ring gear 146a. The pinion case 146b is fixed to the ring gear 146a by screws and rotates integrally with the ring gear 146a. The ring gear 146a and the pinion case 146b are rotatably held in the gear box 108. The pinion shaft 146c is rotatably held in the pinion case 146b. Pinion gear 146d is fixed to pinion shaft 146c. Right drive gear 146e is fixed to right drive shaft 118 and meshes with pinion gear 146d. Left drive gear 146f is fixed to left drive shaft 122 and meshes with pinion gear 146d.

[0037] The differential mechanism 146 further includes a second dog clutch 160. The second dog clutch 160 is slidable in the left-right direction relative to the left drive shaft 122 and is held by the left drive shaft 122 so as to rotate integrally with the left drive shaft 122. The second dog clutch 160 is recessed leftward from its right end and includes a second engagement recess 160a with which the second engagement protrusion 146g of the ring gear 146a can engage. A second compression spring 162 is provided between the second dog clutch 160 and the ring gear 146a. The second compression spring 162 biases the second dog clutch 160 leftward with respect to the left gear case 114 (i.e., in a direction away from the ring gear 146a). The second dog clutch 160 slides in the left-right direction relative to the left drive shaft 122 by a differential lock switching unit 184 (see FIG. 8), which will be described later.

[0038] (Switching unit 110) As shown in FIG. 8, the switching unit 110 is attached to the left gear case 114. As shown in FIG. 9, the switching unit 110 includes a second base plate 180 extending in the front-rear direction, a clutch switching unit 182, and a differential lock switching unit 184. A third operating cable holding portion 186 that holds an end of a first inner cable 64a (see FIG. 8) of the operating cable 64 is provided at the rear of the second base plate 180. As shown in FIG. 10, the second base plate 180 is provided with a first opening 188, a second opening 190, and a third opening 192 that are aligned in the front-rear direction. The first opening 188, the second opening 190, and the third opening 192 extend in the front-rear direction. A front end of the first opening 188 is defined by a first front inner surface 189a of the second base plate 180, and a rear end of the first opening 188 is defined by a first rear inner surface 189b (see FIG. 11) of the second base plate 180. The front end of the second opening 190 is defined by the second front inner surface 191a of the second base plate 180, and the rear end of the second opening 190 is defined by the second rear inner surface 191b of the second base plate 180 (see FIG. 11). The front end of the third opening 192 is defined by the third front inner surface 193a of the second base plate 180, and the rear end of the third opening 192 is defined by the third rear inner surface 193b (see FIG. 11). Three lines, a first position indication line L1, a second position indication line L2, and a third position indication line L3, are provided on the top surface of the second base plate 180 between the third operation cable holding portion 186 and the first opening 188. The three lines, the first position indication line L1, the second position indication line L2, and the third position indication line L3, are lines that notify the user of the position of the switching unit 110 relative to the left gear case 114. A spring mounting portion 194 that protrudes rearward from the second front inner surface 191a is provided in the second opening 190. As shown in Fig. 11, a second protruding portion 114a that protrudes upward from the left gear case 114 is provided between the second rear inner surface 191b of the second base plate 180 and the rear end of the spring mounting portion 194. A third compression spring 196 is attached to the spring mounting portion 194. The rear end of the third compression spring 196 contacts the second protruding portion 114a, and the front end of the third compression spring 196 contacts the second front inner surface 191a (see Fig. 10).The third compression spring 196 biases the second base plate 180 forward relative to the left gear case 114 .

[0039] As shown in FIG. 12 , the clutch switching unit 182 includes a first pin 200, a first rotating portion 202, a second pin 204, and a first slide mechanism 206. As shown in FIG. 11 , the upper portion of the first pin 200 passes through a first opening 188 of the second base plate 180. The outer diameter of the first pin 200 is slightly smaller than the width of the first opening 188 in the left-right direction. Two washers, a first washer 200a and a second washer 200b, are attached to the upper portion of the first pin 200. The second base plate 180 is disposed between the first washer 200a and the second washer 200b in the up-down direction. The outer diameters of the first washer 200a and the second washer 200b are larger than the width of the first opening 188 in the left-right direction. The first pin 200 is supported by the second base plate 180 so as to be slidable in the front-rear direction.

[0040] As shown in FIG. 12, the cross section of the first rotating part 202 in the up-down direction is circular. As shown in FIG. 12, a first upper pin hole 202a is provided on the upper surface of the first rotating part 202. The first upper pin hole 202a is arranged at a position spaced apart from the first rotation axis A1 (see FIG. 11) of the first rotating part 202. The lower part of a first pin 200 is insert-molded or press-fitted into the first upper pin hole 202a. The first pin 200 connects the second base plate 180 and the first rotating part 202. As shown in FIG. 13, a first lower pin hole 202b is provided on the lower surface of the first rotating part 202. The first lower pin hole 202b is arranged at a position spaced apart from the first rotation axis A1 of the first rotating part 202. The first lower pin hole 202b is disposed at a position spaced 90 degrees from the first upper pin hole 202a in the circumferential direction centered on the first rotation axis A1 of the first rotating part 202. The upper part of the second pin 204 (see FIG. 12) is insert-molded or press-fitted into the first lower pin hole 202b. The diameter of the first lower pin hole 202b is the same as the outer diameter of the second pin 204.

[0041] As shown in FIG. 12 , the first slide mechanism 206 includes a first upper slide portion 210 and a first lower slide portion 212. The first upper slide portion 210 is screwed to the first lower slide portion 212. The first upper slide portion 210 includes a first base portion 214 extending in the front-rear direction, a first front mounting portion 216 connected to the front end of the first base portion 214, and a first rear mounting portion 218 connected to the rear end of the first base portion 214. A first elongated hole 214a extending in the front-rear direction is provided on the top surface of the first base portion 214. The lower portion of the second pin 204 is inserted into the first elongated hole 214a. The first rotating portion 202 and the first slide mechanism 206 are connected by the second pin 204. The first base portion 214 has a first through-hole 214b extending in the left-right direction at its front end, and a second through-hole 214c extending in the left-right direction at its rear end. A first support pin 114b (see FIG. 11) extending rightward from the inner wall of the left end of the left gear case 114 is disposed in the first through-hole 214b and the second through-hole 214c. The first lower slide portion 212 has a first push plate 220 extending in the up-down direction. A first front mounting portion 216 and a first rear mounting portion 218 are screwed to the upper portion of the first push plate 220. A first semicircular opening 220a having a semicircular cross section is formed at the lower portion of the first push plate 220. The first dog clutch 156 of the clutch mechanism 144 abuts against the left end of the first push plate 220.

[0042] As shown in FIG. 14 , the differential lock switching unit 184 includes a third pin 230, a second rotating portion 232, a fourth pin 234, and a second slide mechanism 236. As shown in FIG. 11 , the upper portion of the third pin 230 passes through a third opening 192 of the second base plate 180. The outer diameter of the third pin 230 is slightly smaller than the width of the third opening 192 in the left-right direction. Two washers, a third washer 230a and a fourth washer 230b, are attached to the upper portion of the third pin 230. The second base plate 180 is disposed between the third washer 230a and the fourth washer 230b in the up-down direction. The outer diameters of the third washer 230a and the fourth washer 230b are larger than the width of the third opening 192 in the left-right direction. The third pin 230 is supported by the second base plate 180 so as to be slidable in the front-rear direction.

[0043] As shown in FIG. 14, the cross section of the second rotating part 232 in the up-down direction is circular. A second upper pin hole 232a is provided in the upper surface of the second rotating part 232. The second upper pin hole 232a is arranged at a position spaced apart from the second rotation axis A2 (see FIG. 11) of the second rotating part 232. The lower part of the third pin 230 is insert-molded or press-fitted into the second upper pin hole 232a. The third pin 230 connects the second base plate 180 and the second rotating part 232. A second lower pin hole 232b is provided in the lower surface of the second rotating part 232. The second lower pin hole 232b is arranged at a position spaced apart from the second rotation axis A2 of the second rotating part 232. 15, the second lower pin hole 232b is disposed at a position spaced 90 degrees from the second upper pin hole 232a in the circumferential direction centered on the second rotation axis A2 of the second rotating part 232. As shown in Fig. 11, the upper part of the fourth pin 234 is insert-molded or press-fitted into the second lower pin hole 232b. The diameter of the second lower pin hole 232b is the same as the outer diameter of the fourth pin 234.

[0044] As shown in FIG. 14, the second slide mechanism 236 includes a second upper slide portion 240 and a second lower slide portion 242. The second upper slide portion 240 includes a second base portion 244 extending in the front-rear direction, a second front mounting portion 246 (see FIG. 9) connected to the front end of the second base portion 244, and a second rear mounting portion 248 connected to the rear end of the second base portion 244. A second elongated hole 244a extending in the front-rear direction is provided on the upper surface of the second base portion 244. A lower portion of the fourth pin 234 is inserted into the second elongated hole 244a. The fourth pin 234 connects the second rotating portion 232 and the second slide mechanism 236. A third through-hole 244b extending in the left-right direction is provided at the front end of the second base portion 244, and a fourth through-hole 244c extending in the left-right direction is provided at the rear end. A second support pin 114c (see FIG. 11) extending rightward from the inner wall of the left end portion of the left gear case 114 is disposed in the third through-hole 244b and the fourth through-hole 244c. The second lower slide portion 242 is provided with a second push plate 250 extending vertically. A second front mounting portion 246 (see FIG. 9) and a second rear mounting portion 248 are screwed to the upper portion of the second push plate 250. A second semicircular opening 250a having a semicircular cross section is provided at the lower portion of the second push plate 250. The second dog clutch 160 of the differential mechanism 146 abuts against the right end portion of the second push plate 250.

[0045] (First operation: operating the operating lever 52 from the first operating position to the second operating position, or from the second operating position to the first operating position) Next, the operation of the switching unit 110 (see FIG. 9) when the user operates the operating lever 52 in FIG. 3 from the first operating position to the second operating position (see FIG. 5) will be described. Note that, when describing the rotational directions of the first rotating part 202 of the clutch switching unit 182 and the second rotating part 232 of the differential lock switching unit 184 in FIG. 9, the rotational directions will be described when the clutch switching unit 182 and the differential lock switching unit 184 are viewed from above.

[0046] As shown in FIG. 8, when the operating lever 52 (see FIG. 3) is in the first operating position, the switching unit 110 is in the first switching position. As shown in FIG. 7, when the switching unit 110 is in the first switching position, the first engagement protrusion 154a of the second gear 154 is engaged with the first engagement recess 156a of the first dog clutch 156 of the clutch mechanism 144. In this state, the first dog clutch 156 and the second gear 154 rotate integrally. Therefore, power from the motor shaft 136 is transmitted to the ring gear 146a of the differential mechanism 146 via the first intermediate shaft 140 and the second intermediate shaft 142. In this case, the differential mechanism 146 rotates each of the right drive shaft 118 and the left drive shaft 122 in accordance with the power transmitted to the ring gear 146a. Hereinafter, the state of the clutch mechanism 144 in which the first engagement protrusion 154a of the second gear 154 is engaged with the first engagement recess 156a of the first dog clutch 156 will be referred to as the "transmission state." Furthermore, when the switching unit 110 is positioned at the first switching position, the second engagement protrusion 146g of the ring gear 146a of the differential mechanism 146 is not engaged with the second engagement recess 160a of the second dog clutch 160. In this state, a rotational difference between the right drive shaft 118 and the left drive shaft 122 is permitted. Hereinafter, the state of the differential mechanism 146 in which a rotational difference between the right drive shaft 118 and the left drive shaft 122 is permitted will be referred to as the "unlocked state." As shown in FIG. 6, when the switching unit 110 is positioned at the first switching position, only the first position indication line L1 and the second position indication line L2 are located rearward of the cover 111. In this case, the user can see only the first position indication line L1 and the second position indication line L2, and therefore can know that the clutch mechanism 144 is in the transmitted state and the differential mechanism 146 is in the unlocked state. When the switching unit 110 is in the first switching position, the user can use the power transmitted from the motor 106 to move the hand truck 2 and easily turn the hand truck 2 right or left.

[0047] In this embodiment, for example, if the first inner cable 64a of the operating cable 64 breaks, the biasing forces of the first compression spring 158 (see FIG. 7) that contacts the first dog clutch 156 of the clutch mechanism 144, the second compression spring 162 (see FIG. 7) that contacts the second dog clutch 160 of the differential mechanism 146, and the third compression spring 196 (see FIG. 9) that contacts the second base plate 180 are adjusted so that the switching unit 110 moves to the first switching position. With this configuration, even if the first inner cable 64a of the operating cable 64 breaks, the user can apply the brakes to both the right front wheel 100 and the left front wheel 102 when going up a slope, for example.

[0048] As shown in FIG. 5, when the user operates the operating lever 52 from the first operating position to the second operating position, the first inner cable 64a of the operating cable 64 moves forward relative to the first outer cable 64b. In this case, the first inner cable 64a bends between the second operating cable holding portion 128 (see FIG. 16) and the third operating cable holding portion 186 (see FIG. 16) of the switching unit 110. Then, as shown in FIG. 16, the biasing force of the third compression spring 196 causes the second base plate 180 to move forward relative to the left gear case 114. As shown in FIG. 11, when the switching unit 110 is located at the first switching position, the first pin 200 of the clutch switching unit 182 does not contact the first rear inner surface 189b of the first opening 188. The first pin 200 is located slightly forward of the first rear inner surface 189b of the first opening 188. Therefore, as the second base plate 180 moves forward relative to the left gear case 114, the first pin 200 comes into contact with the first rear inner surface 189b of the first opening 188. This causes the second base plate 180 and the first pin 200 to move forward. As the first pin 200 moves forward, the first rotating part 202 rotates clockwise. When the first rotating part 202 in FIG. 9 rotates clockwise, the second pin 204 also rotates clockwise. When the second pin 204 rotates clockwise, the first slide mechanism 206 connected to the second pin 204 moves leftward relative to the left gear case 114, and the first dog clutch 156 abutting against the left end of the first slide mechanism 206 also moves leftward. In this case, as shown in FIG. 17, the first engagement recess 156a of the first dog clutch 156 and the first engagement protrusion 154a of the second gear 154 are disengaged. In this state, even if the first dog clutch 156 rotates, the second gear 154 does not rotate. In other words, the power from the motor shaft 136 is not transmitted to the ring gear 146a of the differential mechanism 146 via the first intermediate shaft 140 and the second intermediate shaft 142. Hereinafter, the state of the clutch mechanism 144 in which the first engaging recess 156a of the first dog clutch 156 is not engaged with the first engaging protrusion 154a of the second gear 154 will be referred to as the "non-transmitting state."11, when the switching unit 110 is in the first switching position, the third pin 230 of the differential lock switching unit 184 does not contact the third front inner surface 193a of the third opening 192. The third pin 230 is located slightly rearward of the third front inner surface 193a of the third opening 192. Therefore, even if the second base plate 180 moves forward relative to the left gear case 114, the third pin 230 does not move. In other words, the differential lock switching unit 184 does not move. In this case, as shown in FIG. 17, the second dog clutch 160 of the differential mechanism 146 connected to the differential lock switching unit 184 also does not move, and a state in which the second engagement protrusion 146g of the ring gear 146a does not engage with the second engagement recess 160a of the second dog clutch 160 (i.e., an unlocked state) is maintained. 16, when the switching unit 110 is in the second switching position, only the first position indication line L1 is located behind the cover 111 (see FIG. 6). In this case, the user can see only the first position indication line L1, and therefore can know that the clutch mechanism 144 is in the non-transmitting state and the differential mechanism 146 is in the unlocked state. When the switching unit 110 is in the second switching position, the user can move the stroller 2 by pushing it, and can easily turn the stroller 2 right or left.

[0049] As described above, when the operating lever 52 of FIG. 1 is operated from the first operating position to the second operating position (see FIG. 5), the switching unit 110 (see FIG. 9) switches the state of the clutch mechanism 144 (see FIG. 17) from the transmitted state to the non-transmitted state without switching the state of the differential mechanism 146 (see FIG. 17). Also, when the user operates the operating lever 52 from the second operating position (see FIG. 5) to the first operating position, the position of the switching unit 110 (see FIG. 9) is switched from the second switching position (see FIG. 16) to the first switching position (see FIG. 9). In this case, as shown in FIG. 7, the switching unit 110 (see FIG. 9) switches the state of the clutch mechanism 144 from the transmitted state to the non-transmitted state without switching the state of the differential mechanism 146. That is, the switching unit 110 of FIG. 9 switches the state of the clutch mechanism 144 (see FIG. 7) to either a transmission state or a non-transmission state in response to a first operation of the user on the operating lever 52 (see FIG. 1) without switching the state of the differential mechanism 146 (see FIG. 7).

[0050] (Second operation: operating the operating lever 52 from the first operating position to the third operating position, or from the third operating position to the first operating position) Next, the operation of the switching unit 110 (see FIG. 9) when the user operates the operating lever 52 in FIG. 3 from the first operating position to the third operating position (see FIG. 4) will be described.

[0051] As shown in FIG. 4, when the user operates the operating lever 52 from the first operating position to the third operating position, the first inner cable 64a of the operating cable 64 moves rearward relative to the first outer cable 64b. In this case, as shown in FIG. 18, the second base plate 180 to which the first inner cable 64a of the operating cable 64 is connected moves rearward relative to the left gear case 114. As shown in FIG. 11, when the operating lever 52 is located at the first operating position, the first pin 200 of the clutch switching unit 182 does not contact the first rear inner surface 189b of the first opening 188. The first pin 200 is located slightly forward of the first rear inner surface 189b of the first opening 188. Therefore, even if the second base plate 180 moves rearward relative to the left gear case 114, the first pin 200 does not move. In other words, the clutch switching unit 182 does not move. In this case, as shown in FIG. 19, the first dog clutch 156 of the clutch mechanism 144 connected to the clutch switching unit 182 also does not move, and the state in which the first engagement protrusion 154a of the second gear 154 is engaged with the first engagement recess 156a of the first dog clutch 156 (i.e., the transmission state) is maintained. Also, as shown in FIG. 11, when the operating lever 52 is in the first operating position, the third pin 230 of the differential lock switching unit 184 does not contact the third front inner surface 193a of the third opening 192. The third pin 230 is positioned slightly rearward of the third front inner surface 193a of the third opening 192. Therefore, as the second base plate 180 moves rearward relative to the left gear case 114, the third pin 230 comes into contact with the third front inner surface 193a of the third opening 192. This causes the second base plate 180 and the third pin 230 to move rearward. As the third pin 230 moves rearward, the second rotating part 232 rotates counterclockwise. As the second rotating part 232 in Fig. 9 rotates clockwise, the fourth pin 234 connected to the second rotating part 232 also rotates clockwise. When the fourth pin 234 rotates counterclockwise, the second slide mechanism 236 connected to the fourth pin 234 moves rightward relative to the left gear case 114, and the second dog clutch 160 of the differential mechanism 146, which is in contact with the right end of the second slide mechanism 236, also moves rightward.In this case, as shown in FIG. 19, the second engagement protrusion 146g of the differential mechanism 146 engages with the second engagement recess 160a of the second dog clutch 160, and in the differential mechanism 146, the ring gear 146a is fixed to the left drive shaft 122, and the right drive shaft 118 and the left drive shaft 122 rotate in the same direction at the same rotation speed. In other words, a difference in rotation between the right drive shaft 118 and the left drive shaft 122 is prohibited. Hereinafter, the state of the differential mechanism 146 when a difference in rotation between the right drive shaft 118 and the left drive shaft 122 is prohibited is referred to as a "locked state." Note that, when the switching unit 110 is positioned in the third switching position as shown in FIG. 18, the first position indication line L1, the second position indication line L2, and the third position indication line L3 are located rearward of the cover 111 (see FIG. 6). In this case, the first position indication line L1, the second position indication line L2, and the third position indication line L3 are visible to the user, so the user can know that the clutch mechanism 144 is in the transmitted state and that the differential mechanism 146 is in the locked state. When the switching unit 110 is in the third switching position, the user can use the power transmitted from the motor 106 to move the hand truck 2 straight forward. Furthermore, for example, when only one of the right front wheel 100 and the left front wheel 102 is in contact with the ground, the power from the motor 106 can be transmitted to the wheel that is in contact with the ground.

[0052] As described above, when the operating lever 52 in FIG. 3 is operated from the first operating position to the third operating position (see FIG. 5), the switching unit 110 (see FIG. 9) switches the state of the differential mechanism 146 (see FIG. 19) from the unlocked state to the locked state without switching the state of the clutch mechanism 144 (see FIG. 19). Also, when the user operates the operating lever 52 from the third operating position (see FIG. 5) to the first operating position, the position of the switching unit 110 is switched from the third switching position (see FIG. 18) to the first switching position (see FIG. 8). In this case, as shown in FIG. 7, the switching unit 110 switches the state of the differential mechanism 146 from the locked state to the unlocked state without switching the state of the clutch mechanism 144. That is, the switching unit 110 of FIG. 9 switches the state of the differential mechanism 146 (see FIG. 7) to either the unlocked state or the locked state in response to the user's second operation of the operating lever 52 (see FIG. 1) without switching the state of the clutch mechanism 144 (see FIG. 7).

[0053] In one or more embodiments, as shown in FIGS. 1 to 19 , the hand truck 2 includes a motor 106 (an example of a “prime mover”), a right front wheel 100 (an example of a “first ground contact portion”) and a left front wheel (an example of a “second ground contact portion”) driven by the prime mover, a clutch mechanism 144 switchable between a transmission state in which power from the motor 106 is transmitted to the right front wheel 100 and the left front wheel 102 and a non-transmission state in which power from the motor 106 is not transmitted to the right front wheel 100 and the left front wheel 102, and a clutch mechanism 144 that is switchable between a transmission state in which power from the motor 106 is transmitted to the right front wheel 100 and the left front wheel 102 and a non-transmission state in which power from the motor 106 is not transmitted to the right front wheel 100 and the left front wheel 102. The differential mechanism 146 distributes power from the clutch mechanism 144 to the right front wheel 100 and the left front wheel 102, and is switchable between an unlocked state that allows a difference in rotation between the right front wheel 100 and the left front wheel 102, and a locked state that prohibits a difference in rotation between the right front wheel 100 and the left front wheel 102; a second base plate 180 (an example of a "switching unit") for switching the state of the clutch mechanism 144 and the state of the differential mechanism 146; and an operating lever 52 (an example of an "operating unit"). The second base plate 180 is configured to switch the state of the clutch mechanism 144 between a transmitted state and a non-transmitted state in response to a first operation of the operating lever 52 by the user, without switching the state of the differential mechanism 146, and to switch the state of the differential mechanism 146 between a locked state and an unlocked state in response to a second operation of the operating lever 52 by the user, without switching the state of the clutch mechanism 144. According to the above configuration, the second base plate 180 can realize three states: a state in which the differential mechanism 146 is in an unlocked state and the clutch mechanism 144 is in a transmitted state; a state in which the differential mechanism 146 is in an unlocked state and the clutch mechanism 144 is in a non-transmitted state; and a state in which the differential mechanism 146 is in a locked state and the clutch mechanism 144 is in a transmitted state. This can improve user convenience.

[0054] 1 to 19, the hand truck 2 includes a motor 106, a right front wheel 100 and a left front wheel 102 driven by the motor 106, a clutch mechanism 144 that can be switched to either a transmission state in which power from the motor 106 is transmitted to the right front wheel 100 and the left front wheel 102, or a non-transmission state in which power from the motor 106 is not transmitted to the right front wheel 100 and the left front wheel 102, a differential mechanism 146 that distributes power from the motor 106 to the right front wheel 100 and the left front wheel 102, and that can be switched to either an unlocked state in which a rotational difference is allowed to occur between the right front wheel 100 and the left front wheel 102, or a locked state in which a rotational difference is prohibited between the right front wheel 100 and the left front wheel 102, a second base plate 180 for switching the state of the clutch mechanism 144 and the state of the differential mechanism 146, and an operating lever 52. In response to a user's operation of the operating lever 52, the second base plate 180 moves to one of a first switching position (an example of a "first position") where the differential mechanism 146 is in an unlocked state and the clutch mechanism 144 is in a transmitted state, a second switching position (an example of a "second position") where the differential mechanism 146 is in an unlocked state and the clutch mechanism 144 is in a disengaged state, and a third switching position (an example of a "third position") where the differential mechanism 146 is in a locked state and the clutch mechanism 144 is in a transmitted state. According to the above configuration, the second base plate 180 realizes three states: a state where the differential mechanism 146 is in an unlocked state and the clutch mechanism 144 is in a transmitted state, a state where the differential mechanism 146 is in an unlocked state and the clutch mechanism 144 is in a disengaged state, and a state where the differential mechanism 146 is in a locked state and the clutch mechanism 144 is in a transmitted state. This improves user convenience.

[0055] 7, 8, and 16 to 19, the second base plate 180 moves in the front-to-rear direction (an example of the "first direction") to switch the state of the clutch mechanism 144 and / or the state of the differential mechanism 146. According to the above configuration, the configuration of the hand transport vehicle 2 can be simplified compared to a configuration in which the state of the clutch mechanism 144 and / or the state of the differential mechanism 146 is switched by rotating the second base plate 180 in response to the user's operation of the operating lever 52.

[0056] For example, if the state of the clutch mechanism 144 is switched from the transmitted state to the non-transmitted state, the stroller 2 may unintentionally move up a slope even if the motor 106 is stopped. In one or more embodiments, as shown in FIG. 1 , the stroller 2 further includes a handle unit 10 (an example of a "handle") that can be held by a user. The operating lever 52 is provided on the handle unit 10. With the above configuration, the user can hold the handle unit 10 with one hand while operating the operating lever 52 with the other hand. This prevents the stroller 2 from unintentionally moving up a slope, and allows the stroller 2 to remain stopped.

[0057] 8, the second base plate 180 is provided with a first position indication line L1, a second position indication line L2, and a third position indication line L3 (examples of "position indication portions") that indicate the position of the second base plate 180 relative to the clutch mechanism 144 and the differential mechanism 146. According to the above configuration, the user can understand the state of the clutch mechanism 144 and the state of the differential mechanism 146 by checking the position of the second base plate 180 indicated by the first position indication line L1, the second position indication line L2, and the third position indication line L3. This can further improve user convenience.

[0058] (First Modification) The hand truck 2 may be able to realize a state in which the clutch mechanism 144 is in the non-transmitting state and the differential mechanism 146 is in the locked state by the second base plate 180.

[0059] (Second Modification) The "first ground contact portion" and the "second ground contact portion" are not limited to wheels, and may be rollers, crawlers, or the like.

[0060] (Third Modification) The "prime mover" is not limited to the motor 106, but may be an engine.

[0061] (Fourth Modification) The state of the clutch mechanism 144 and / or the state of the differential mechanism 146 may be switched by the rotational movement of the "switching portion." For example, as shown in FIG. 20 , a switching unit 410 may include a clutch switching unit 412 and a differential lock switching unit 414. The clutch switching unit 412 is disposed above and forward of the differential lock switching unit 414. The clutch switching unit 412 includes a clutch switching cam 420, a clutch switching pin 422, and a first link mechanism 424. A right end 422a of the clutch switching pin 422 is fixed to the first dog clutch 156, and a left end 422b is in contact with the outer circumferential surface of the clutch switching cam 420. The first link mechanism 424 rotates the clutch switching cam 420 about the third rotation axis A3 in response to a user's operation of the operating lever 52 (see FIG. 1 ). In this modified example, a compression spring (not shown) is provided between the second gear 154 and the first dog clutch 156 to bias the first dog clutch 156 leftward relative to the second gear 154. When the left end 422b of the clutch switch pin 422 is in contact with the first arcuate surface 420a of the clutch switch cam 420, the first engagement protrusion 154a of the second gear 154 is engaged with the first engagement recess 156a of the first dog clutch 156. In other words, the clutch mechanism 144 is in a transmission state. The differential lock switch unit 414 includes a differential lock switch cam 430, a differential lock switch pin 432, and a second link mechanism 434. The right end 432a of the differential lock switch pin 432 is fixed to the second dog clutch 160, and the left end 432b is in contact with the outer circumferential surface of the differential lock switch cam 430. The second link mechanism 434 rotates the differential lock switch cam 430 about the fourth rotation axis A4 in response to a user's operation of the operating lever 52 (see FIG. 1). In this modified example, a compression spring (not shown) that urges the second dog clutch 160 leftward relative to the ring gear 146a is provided between the ring gear 146a and the second dog clutch 160. When the left end 432b of the differential lock switch pin 432 is in contact with the first flat surface 430a of the differential lock switch cam 430, the second engagement protrusion 146g of the ring gear 146a is not engaged with the second engagement recess 160a of the second dog clutch 160.That is, the state of the differential mechanism 146 is the unlocked state.

[0062] In this modification, when the operating lever 52 is operated from the first operating position (see FIG. 3) to the second operating position (see FIG. 5), the clutch switch cam 420 and the differential lock switch cam 430 rotate clockwise. In this case, the left end 422b of the clutch switch pin 422 comes into contact with the flat surface 420b of the clutch switch cam 420, and the first dog clutch 156 moves leftward relative to the second gear 154. This disengages the first engagement recess 156a of the first dog clutch 156 from the first engagement protrusion 154a of the second gear 154. In other words, the state of the clutch mechanism 144 is switched from the transmission state to the non-transmission state. In addition, the left end 432b of the differential lock switch pin 432 comes into contact with the second flat surface 430b of the differential lock switch cam 430. In this case, the second engaging protrusion 146g of the ring gear 146a is maintained in a state where it is not engaged with the second engaging recess 160a of the second dog clutch 160 (that is, an unlocked state).

[0063] In this modification, when the operating lever 52 is operated from the first operating position (see FIG. 3) to the third operating position (see FIG. 4), the clutch switch cam 420 and the differential lock switch cam 430 rotate counterclockwise. In this case, the left end 422b of the clutch switch pin 422 is maintained in contact with the first arcuate surface 420a of the clutch switch cam 420 (i.e., the transmission state). Meanwhile, the left end 432b of the differential lock switch pin 432 comes into contact with the second arcuate surface 430c of the differential lock switch cam 430, and the second dog clutch 160 moves rightward relative to the ring gear 146a. As a result, the second engaging protrusion 146g of the ring gear 146a engages with the second engaging recess 160a of the second dog clutch 160. In other words, the state of the differential mechanism 146 is switched from unlocked to locked. This configuration can also achieve the same effects as the embodiment. In this modification, the clutch switching cam 420 and the differential lock switching cam 430 are an example of a "switching portion."

[0064] (Fifth Modification) The "operating unit" may be provided in a location different from the handle unit 10, for example, on the chassis frame 14. In another modification, the "operating unit" and the "switching unit" may be formed integrally without a link mechanism or the like.

[0065] (Sixth Modification) The push cart 2 may be provided with a loop handle instead of the handle unit 10. For example, the loop handle may include a right support portion extending upward from the right end of the chassis frame 14 in FIG. 1, a right extension portion extending rearward from the upper end of the right support portion, a left support portion extending upward from the left end of the chassis frame 14 (see FIG. 1), a left extension portion extending rearward from the upper end of the left support portion, and a grip portion connecting the rear end of the right extension portion and the rear end of the left extension portion. In this modification, the "operating portion" may be provided on the right extension portion.

[0066] (Seventh Modification) The first position indication line L1, the second position indication line L2, and the third position indication line L3 may not be provided on the second base plate 180. In other words, the "position indication portion" can be omitted.

[0067] (Eighth Modification) For example, the biasing forces of the first compression spring 158, the second compression spring 162, and the third compression spring 196 may be adjusted so that the switching unit 110 is positioned at the second switching position when the first inner cable 64a of the operation cable 64 breaks. In this case, the user can manually move the hand truck 2 when the first inner cable 64a of the operation cable 64 breaks. In another modification, the biasing forces of the first compression spring 158, the second compression spring 162, and the third compression spring 196 may be adjusted so that the switching unit 110 is positioned at the third switching position when the first inner cable 64a of the operation cable 64 breaks. In this case, even when the first inner cable 64a of the operation cable 64 breaks, the hand truck 2 can be moved linearly using the power transmitted from the motor 106. [Explanation of symbols]

[0068] 2: Hand-operated transport cart 4: Chassis unit 6: Cargo unit 10: Handle unit 12: Battery box 12a: Battery pack 12b: Control device 14: Chassis frame 16: Front wheel unit 18: Rear wheel unit 20: Handle base 22: Right-hand drive 24: Left-hand drive 30: Right pipe 30a: Right side support part 30b: Right handle 32: Right grip 34: Switch box 36: Drive lever 38: Operation unit 40: Switch casing 42: Operation panel 42a: Main power switch 42b: Reverse switch 42c: Speed ​​switch 44: Drive switch 50: Operation casing 50a:Top surface 52: Control lever 54: First operating cable holding part 56: Right side holding part 58:Left side holding part 58a: Intermediate notch 58b: Rear notch 58c: Front notch 60: Grip part 62: Lock unit 62a: Lock button 62b: Fitting part 64: Control cable 64a: First inner cable 64b: First outer cable 70: Left pipe 70b: Left handle 72: Left grip 74: Brake casing 76: Brake lever 78: Brake cable holder 80: Brake cable 80a: Second inner cable 80b: Second outer cable 90: First base plate 92: Right rear wheel 100: Right front wheel 102: Left front wheel 104: Brake unit 106: Motor 108: Gearbox 110: Switching unit 111: Cover 112: Right gear case 114: Left gear case 114a: Second protrusion 114b: First support pin 114c: Second support pin 116: Right hub 118: Right drive shaft 120: Left hub 122: Left drive shaft 124: 1st protrusion 126: Stretching part 126a: Left end of extension 128: Second operating cable holder 130: Stator 132: Rotor 134: Motor case 136: Motor shaft 136a: 1st spur gear 140: First intermediate shaft 142: Second intermediate shaft 144: Clutch mechanism 146:Differential mechanism 146a: Ring gear 146b: Pinion case 146c: Pinion shaft 146d: Pinion gear 146e: Right drive gear 146f: Left drive gear 146g: 2nd engagement convex part 150: 1st gear 152: Second spur gear 154: 2nd gear 154a: First engagement convex part 156: First dog clutch 156a: First engagement recess 158: First compression spring 160: Second dog clutch 160a: Second engagement recess 162: Second compression spring 180: Second base plate 182: Clutch switching unit 184: Differential lock switching unit 186: Third operating cable holder 188: First opening 189a: 1st front inner surface 189b: First rear inner surface 190: Second opening 191a: 2nd front inner surface 191b: Second rear inner surface 192: Third opening 193a: 3rd front inner surface 193b: Third posterior inner surface 194: Spring mounting part 196: Third compression spring 200: 1st pin 200a: First washer 200b: Second washer 202: First rotating part 202a: 1st upper pin hole 202b: 1st lower pin hole 204: 2nd pin 206: First slide mechanism 210: First upper slide part 212: First lower slide part 214 :1st base 214a: 1st long hole 214b: 1st through hole 214c: 2nd through hole 216: First front mounting part 218: First rear mounting part 220: First push plate 220a: First semicircular opening 230: 3rd pin 230a: Third washer 230b: 4th washer 232: Second rotating part 232a: 2nd upper pin hole 232b: 2nd lower pin hole 234: 4th pin 236: Second slide mechanism 240: Second upper slide 242: Second lower slide part 244:Second base 244a: 2nd long hole 244b: 3rd through hole 244c: 4th through hole 246: Second front mounting part 248: Second rear mounting part 250: Second push plate 250a: Second semicircular opening 300: Bucket 302: Cargo frame 410: Switching unit 412: Clutch switching unit 414: Differential lock switching unit 420: Clutch switching cam 420a: First arc surface 420b: flat surface 422: Clutch switching pin 422a: Right end of clutch switching pin 422b: Left end of clutch switching pin 424: First link mechanism 430: Differential lock switching cam 430a: 1st flat surface 430b: 2nd flat surface 430c: Second arc surface 432: Differential lock switching pin 432a: Right end of differential lock switching pin 432b: Left end of differential lock switching pin 434: Second link mechanism

Claims

1. The prime mover and a first ground contact portion and a second ground contact portion driven by the prime mover; a clutch mechanism switchable between a transmission state in which power from the prime mover is transmitted to the first ground contact portion and the second ground contact portion and a non-transmission state in which power from the prime mover is not transmitted to the first ground contact portion and the second ground contact portion; a differential mechanism that distributes power from the prime mover to the first ground contact portion and the second ground contact portion, the differential mechanism being switchable between an unlocked state that allows a rotational difference to occur between the first ground contact portion and the second ground contact portion, and a locked state that prohibits the rotational difference from occurring between the first ground contact portion and the second ground contact portion; a switching unit for switching a state of the clutch mechanism and a state of the differential mechanism; One operation unit; Equipped with The switching unit is In response to a first operation of the one operation unit by a user, the state of the clutch mechanism can be switched between the transmitted state and the non-transmitted state without switching the state of the differential mechanism, and In response to a second operation of the one operation unit by the user, the state of the differential mechanism can be switched to either the unlocked state or the locked state without switching the state of the clutch mechanism. Hand-operated transport vehicle.

2. The prime mover and a first ground contact portion and a second ground contact portion driven by the prime mover; a clutch mechanism switchable between a transmission state in which power from the prime mover is transmitted to the first ground contact portion and the second ground contact portion and a non-transmission state in which power from the prime mover is not transmitted to the first ground contact portion and the second ground contact portion; a differential mechanism that distributes power from the prime mover to the first ground contact portion and the second ground contact portion, the differential mechanism being switchable between an unlocked state that allows a rotational difference to occur between the first ground contact portion and the second ground contact portion, and a locked state that prohibits the rotational difference from occurring between the first ground contact portion and the second ground contact portion; a switching unit for switching a state of the clutch mechanism and a state of the differential mechanism; An operation unit; Equipped with The switching unit, in response to a user's operation on the operation unit, a first position in which the differential mechanism is in the unlocked state and the clutch mechanism is in the transmitted state; a second position in which the differential mechanism is in the unlocked state and the clutch mechanism is in the non-transmitting state; a third position in which the differential mechanism is in the locked state and the clutch mechanism is in the transmitted state; , which can be moved to any of the positions Hand-operated transport vehicle.

3. The hand transport vehicle according to claim 1 or 2, wherein the state of the clutch mechanism and / or the state of the differential mechanism is switched by the movement of the switching portion along a first direction.

4. The hand truck further comprises: a handle that can be gripped by the user; The hand transport vehicle according to claim 1 , wherein the operating part is provided on the handle.

5. The hand transport vehicle according to claim 1 , wherein the switching unit is provided with a position indicator that indicates the position of the switching unit relative to the clutch mechanism and the differential mechanism.

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