Lock

Abstract

The embodiment of the utility model provides a lock. The lock is used for solving the problem of how to reduce driving force needing to be applied to a key when the key is used for unlocking. The lock comprises a base body, a lock cylinder shifting block, a speed reducing mechanism, a locking and unlocking shifting block and a spring bolt. The lock cylinder shifting block is rotationally connected with the base body and can rotate under the condition of being driven by a key, the speed reducing mechanism is arranged on the base body and comprises a first gear and a second gear which are in transmission connection, the ratio of the rotating speed of the first gear to the rotating speed of the second gear is larger than 1, and the lock cylinder shifting block is used for driving the first gear to rotate. The second gear is in transmission connection with the locking and unlocking shifting block, the locking and unlocking shifting block is rotationally connected with the base body, the second gear is used for driving the locking and unlocking shifting block to rotate, and the locking and unlocking shifting block is used for driving the spring bolt to move.

Description

Technical Field

[0001] The present application relates to the technical field of lock design, and in particular to a lock. Background Art

[0002] Locks are widely used in daily life. For example, locks are generally installed on various doors. Locks are generally provided with a lock cylinder. By inserting a key into the lock cylinder and turning the key, the lock cylinder head can be driven to rotate. Furthermore, the lock cylinder head can be used to directly drive the lock tongue to perform telescopic movement. The solution in which the lock cylinder head directly drives the lock tongue to perform telescopic movement has the problem that the resistance is large when the key is used to unlock the lock, and the operator needs to apply a large driving force to the key. Utility Model Content

[0003] The embodiment of the present application provides a lock device to solve the problem of how to reduce the driving force that needs to be applied to the key when unlocking the lock with the key.

[0004] The lock provided by the embodiment of the present application includes: a base, a lock core dial, a reduction mechanism, a locking and unlocking dial and a lock tongue; the lock core dial is rotatably connected to the base, and the lock core dial can rotate when driven by a key, the reduction mechanism is arranged on the base, the reduction mechanism includes a first gear and a second gear that are transmission-connected, the ratio of the rotation speed of the first gear to the rotation speed of the second gear is greater than 1, the lock core dial is used to drive the first gear to rotate, the second gear is transmission-connected to the locking and unlocking dial, the locking and unlocking dial is rotatably connected to the base, the second gear is used to drive the locking and unlocking dial to rotate, and the locking and unlocking dial is used to drive the lock tongue to move.

[0005] Optionally, the first gear is provided with a notch portion, the lock core dial head comprises a rotating portion and a toggling portion connected to each other, the first gear is wound around the outside of the rotating portion, and the toggling portion is provided in the notch portion.

[0006] Optionally, the deceleration mechanism further includes a third gear and a fourth gear, the third gear is meshed with the first gear and the fourth gear respectively, and the fourth gear is transmission-connected with the second gear.

[0007] Optionally, the first gear is a sector gear, the first gear is arranged around the rotating part of the lock core switch head, and the switching part of the lock core switch head is arranged in the notch part of the first gear; the reduction mechanism also includes a fifth gear, the pitch circle diameter of the fifth gear is equal to the pitch circle diameter of the third gear, the fifth gear is meshed with the fourth gear, and when the third gear is opposite to the notch part, the fifth gear is meshed with the first gear.

[0008] Optionally, the pitch circle diameter of the third gear is smaller than the pitch circle diameter of the first gear, and the pitch circle diameter of the third gear is smaller than the pitch circle diameter of the fourth gear.

[0009] Optionally, the deceleration mechanism also includes a sixth gear, the pitch circle diameter of the sixth gear is smaller than the pitch circle diameter of the fourth gear, the sixth gear is coaxially connected to the fourth gear, the sixth gear can rotate synchronously with the fourth gear, and the sixth gear is transmission connected to the second gear.

[0010] Optionally, the speed reduction mechanism further includes a seventh gear, the pitch circle diameter of the seventh gear is smaller than the pitch circle diameter of the second gear, and the seventh gear is respectively meshed with the sixth gear and the second gear.

[0011] Optionally, the rotating shaft of the first gear, the rotating shaft of the fourth gear, the rotating shaft of the seventh gear and the rotating shaft of the second gear are parallel to each other and coplanar.

[0012] Optionally, the second gear is provided with a boss protruding along its own axial direction, and the locking and unlocking dial head is connected to the boss.

[0013] Optionally, a ratio of a rotation speed of the first gear to a rotation speed of the second gear is greater than or equal to 2 and less than or equal to 4.

[0014] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects:

[0015] In an embodiment of the present application, the lock cylinder dial is used to drive the first gear to rotate, the ratio of the rotational speed of the first gear of the reduction mechanism to the rotational speed of the second gear is greater than, the second gear is used to drive the locking and unlocking dial to rotate, and the locking and unlocking dial is used to drive the lock tongue to move. In this way, during the process of unlocking or closing the lock, the driving force required to be applied to the key when unlocking the lock can be reduced by increasing the rotation angle of the key. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 A schematic diagram of a lock provided in an embodiment of the present application;

[0018] Figure 2A partial schematic diagram of a lock provided in an embodiment of the present application, which shows a situation where a cover body of the main lock is hidden;

[0019] Figure 3 A partial schematic diagram of a lock provided by an embodiment of the present application, which shows a situation where a cover body of the main lock and a second sub-housing of a speed reduction mechanism are hidden;

[0020] Figure 4 for Figure 3 A partial schematic diagram of the lock shown in FIG.

[0021] Figure 5 A schematic diagram of a lock core dial, a speed reduction mechanism and a locking and unlocking dial provided in an embodiment of the present application;

[0022] Figure 6 An exploded schematic diagram of a lock core dial, a speed reduction mechanism, and a locking and unlocking dial provided in an embodiment of the present application;

[0023] Figure 7 A schematic diagram of a lock cylinder dial head, a speed reduction mechanism and a locking and unlocking dial head provided in an embodiment of the present application, which shows a situation where the second sub-housing in which the speed reduction mechanism is hidden;

[0024] Figure 8 A schematic diagram of a lock cylinder dial head, a speed reduction mechanism and a locking and unlocking dial head provided in an embodiment of the present application, which shows a situation where the second sub-housing in which the speed reduction mechanism is hidden;

[0025] Fig. 9 A schematic diagram of a lock cylinder dial, a speed reduction mechanism and a locking and unlocking dial provided in an embodiment of the present application, which shows a situation in which the first sub-housing in which the speed reduction mechanism is hidden.

[0026] Description of reference numerals:

[0027] 100-lock; 100a-main lock; 100b-first secondary lock; 100c-second secondary lock; 110-base; 120-lock cylinder dial; 121-rotating part; 122-moving part; 130-speed reduction mechanism; 131-first gear; 1311-notch part; 132-second gear; 1321-boss; 133-third gear; 134-fourth gear; 135-fifth gear; 136-sixth gear; 137-seventh gear; 138-housing; 1381-first subhousing; 1382-second subhousing; 140-locking and unlocking dial; 150-lock tongue; 151-first lock tongue; 152-second lock tongue; 160-transmission mechanism; 170-driver. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0029] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0030] In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article.

[0031] Furthermore, it is required that the present application be understood not only by the actual terms used but also by the meanings connoted by each term.

[0032] The technical solutions provided by various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0033] The present application embodiment provides a lock. Figures 1 to 9 The lock 100 provided in the embodiment of the present application includes: a base 110, a lock core dial 120, a speed reduction mechanism 130, a locking and unlocking dial 140, and a lock tongue 150. The base 110 is the installation base of various components in the lock 100. Exemplarily, the base 110 may include a lock shell and a frame.

[0034] The lock cylinder head 120 is rotatably connected to the base 110, and the lock cylinder head 120 can rotate when driven by a key. It can be understood that the key used to drive the lock cylinder head 120 to rotate is a key that matches the lock 100. In addition, the solution of driving the lock cylinder head 120 to rotate by turning the key can be understood in combination with common knowledge in the art.

[0035] The speed reduction mechanism 130 is disposed on the base 110. The speed reduction mechanism 130 includes a first gear 131 and a second gear 132 which are transmission-connected, and the ratio of the rotation speed of the first gear 131 to the rotation speed of the second gear 132 is greater than 1. In other words, the speed ratio of the first gear 131 to the second gear 132 is greater than 1. For example, if the speed ratio of the first gear 131 to the second gear 132 is 3, when the key rotates one circle, the lock cylinder head 120 rotates one circle, and the second gear 132 rotates one third of a circle, that is, the second gear 132 rotates 120 degrees.

[0036] refer to Figures 2 to 5 The lock cylinder head 120 is used to drive the first gear 131 to rotate, the second gear 132 is in transmission connection with the locking and unlocking head 140, the locking and unlocking head 140 is in rotation connection with the base 110, the second gear 132 is used to drive the locking and unlocking head 140 to rotate, and the locking and unlocking head 140 is used to drive the lock tongue 150 to move. Exemplarily, the lock tongue 150 is slidably connected to the base 110, so that the lock tongue 150 can move telescopically relative to the base 110. For example, when the lock tongue 150 is in the extended position, the lock 100 is in a locked state; when the lock tongue 150 is in the retracted position, the lock 100 is in an unlocked state.

[0037] Exemplarily, when the lock 100 is in a locked state, the locking and unlocking dial 140 needs to be rotated 120 degrees to drive the lock tongue 150 to switch from the extended position to the retracted position. The solution provided in the embodiment of the present application is adopted. For example, the speed ratio of the first gear 131 and the second gear 132 is 3, and the key needs to be used to drive the key and the lock cylinder dial 120 to rotate synchronously for one circle, so that the lock 100 can be in an unlocked state. On the basis of the lock involved in the related art, the key of the lock drives the locking and unlocking dial to rotate synchronously, and the lock 100 can be unlocked by driving the key to rotate 120 degrees. The solution provided in the embodiment of the present application can reduce the resistance when unlocking with the key by increasing the rotation angle of the key.

[0038] In this way, in an embodiment of the present application, the lock cylinder dial head 120 is used to drive the first gear 131 to rotate, the ratio of the rotational speed of the first gear 131 of the reduction mechanism 130 to the rotational speed of the second gear 132 is greater than 1, and the second gear 132 is used to drive the locking and unlocking dial head 140 to rotate, and the locking and unlocking dial head 140 is used to drive the lock tongue 150 to move. In this way, in the process of unlocking or closing the lock, the driving force required to be applied to the key when unlocking the lock can be reduced by increasing the rotation angle of the key.

[0039] refer to Figure 7In some embodiments, the first gear 131 is provided with a notch 1311. The lock core dial head 120 includes a rotating portion 121 and a toggle portion 122 connected to each other, the first gear 131 is arranged around the rotating portion 121, and the toggle portion 122 is arranged in the notch 1311. In this way, the lock core dial head 120 can be driven to rotate by turning the key, so that the toggle portion 122 of the lock core dial head 120 can be used to drive the first gear 131 to rotate. In addition, in other embodiments, the lock core dial head 120 can also be directly connected to the first gear 131, so that the first gear 131 can be driven to rotate synchronously with the lock core dial head 120.

[0040] refer to Figure 7 In some embodiments, the speed reduction mechanism 130 further includes a third gear 133 and a fourth gear 134. The third gear 133 is meshed with the first gear 131 and the fourth gear 134 respectively, and the fourth gear 134 is transmission-connected with the second gear 132. In this way, the power of the first gear 131 can be transmitted to the second gear 132 by using the third gear 133 and the fourth gear 134.

[0041] Combination Figure 6 In some embodiments, the first gear 131 is a sector gear. In other words, the first gear 131 is an incomplete gear. The first gear 131 is disposed around the rotating portion 121 of the lock cylinder head 120, and the shifting portion 122 of the lock cylinder head 120 is disposed in the notch portion 1311 of the first gear 131.

[0042] In order to avoid the interruption of the power transmission between the third gear 133 and the first gear 131 when the third gear 133 is opposite to the notch 1311, so that the power of the first gear 131 cannot be smoothly transmitted to the fourth gear 134, in some embodiments, the speed reduction mechanism 130 further includes a fifth gear 135. The pitch circle diameter of the fifth gear 135 is equal to the pitch circle diameter of the third gear 133, and the fifth gear 135 is meshed with the fourth gear 134. When the third gear 133 is opposite to the notch 1311, the fifth gear 135 is meshed with the first gear 131. In this way, when the third gear 133 is opposite to the notch 1311, the power of the first gear 131 can be transmitted to the fourth gear 134 via the fifth gear 135.

[0043] It should be noted that, in other embodiments, when the first gear 131 is a complete gear, the power transmission between the third gear 133 and the first gear 131 will not be interrupted, and therefore, the fifth gear 135 may not be provided.

[0044] refer to Figure 7 and Figure 8In some embodiments, the pitch circle diameter of the third gear 133 is smaller than the pitch circle diameter of the first gear 131, and the pitch circle diameter of the third gear 133 is smaller than the pitch circle diameter of the fourth gear 134. In this way, the diameters of the first gear 131 and the fourth gear 134 can be made larger, so that the third gear 133 is easily meshed with the first gear 131 and the fourth gear 134, and the fifth gear 135 is easily meshed with the first gear 131 and the fourth gear 134.

[0045] refer to Figures 7 to 9 In some embodiments, the speed reduction mechanism 130 further includes a sixth gear 136. The pitch circle diameter of the sixth gear 136 is smaller than the pitch circle diameter of the fourth gear 134. The sixth gear 136 is coaxially connected to the fourth gear 134, and the sixth gear 136 can rotate synchronously with the fourth gear 134. The sixth gear 136 is transmission-connected to the second gear 132. In this way, the power of the first gear 131 can be transmitted to the sixth gear 136 via the third gear 133 and the fourth gear 134, and then the sixth gear 136 can drive the second gear 132 to rotate, so as to drive the locking and unlocking dial head 140 to rotate.

[0046] In some embodiments, the speed reduction mechanism 130 further includes a seventh gear 137. The pitch circle diameter of the seventh gear 137 is smaller than the pitch circle diameter of the second gear 132, and the seventh gear 137 is meshed with the sixth gear 136 and the second gear 132 respectively. In this way, the power of the first gear 131 can be transmitted to the sixth gear 136 via the third gear 133 and the fourth gear 134, and the power of the sixth gear 136 can be transmitted to the second gear 132 via the seventh gear 137, thereby driving the locking and unlocking dial 140 to rotate. Among them, since the pitch circle diameter of the seventh gear 137 is smaller than the pitch circle diameter of the second gear 132, the seventh gear 137 can be used to achieve a speed reduction effect.

[0047] refer to Figures 5 to 9 In some embodiments, the speed reduction mechanism 130 further includes a housing 138. Each gear may be disposed in the housing 138. Exemplarily, the housing 138 includes a first sub-housing 1381 and a second sub-housing 1382, and the first sub-housing 1381 and the second sub-housing 1382 are spliced ​​to form the housing 138.

[0048] Combination Figure 7 In some embodiments, the rotating shafts of the first gear 131, the fourth gear 134, the seventh gear 137 and the second gear 132 are parallel and coplanar. In this way, the distance between the lock cylinder head 120 and the locking and unlocking head 140 can be met by gear transmission.

[0049] refer to Figure 6In some embodiments, the second gear 132 is provided with a boss 1321 protruding along its own axial direction. The locking and unlocking dial head 140 is connected to the boss 1321. Exemplarily, the boss 1321 is a hexagonal boss, and the locking and unlocking dial head 140 is provided with a hexagonal groove, and the hexagonal boss is inserted into the hexagonal groove. Therefore, during the rotation of the second gear 132, the locking and unlocking dial head 140 can be driven to rotate synchronously.

[0050] In addition, in other embodiments, the circumference of the boss 1321 is provided with a first convex-concave surface, the locking and unlocking dial head 140 is provided with a groove, and the groove wall of the groove is provided with a second convex-concave surface. The first convex-concave surface is engaged with the second convex-concave surface, so that the locking and unlocking dial head 140 can rotate synchronously with the second gear 132 by the way that the first convex-concave surface and the second convex-concave surface are matched and connected.

[0051] Exemplarily, the circumferential side of the boss 1321 is provided with a first plane, the locking and unlocking dial head 140 is provided with a groove, and the groove wall of the groove is provided with a second plane. When the boss 1321 is inserted into the groove, the first plane contacts the second plane. In this way, the locking and unlocking dial head 140 can also rotate synchronously with the second gear 132. In addition, the locking and unlocking dial head 140 can be connected by interference fit or glue bonding, etc., so that the locking and unlocking dial head 140 and the second gear 132 can rotate synchronously. They are not listed here one by one.

[0052] In some embodiments, the ratio of the rotation speed of the first gear 131 to the rotation speed of the second gear 132 is greater than or equal to 2 and less than or equal to 4. For example, the ratio of the rotation speed of the first gear 131 to the rotation speed of the second gear 132 is 3. In this way, during the process of unlocking or locking, the user will not drive the key to rotate too many times.

[0053] refer to Figure 4 In some embodiments, the lock tongue 150 includes a first lock tongue 151 and a second lock tongue 152. For example, the first lock tongue 151 is an oblique tongue, and the second lock tongue 152 is a square tongue. The lock 100 includes a transmission mechanism 160. The locking and unlocking dial head 140 is in transmission connection with the transmission mechanism 160, and the power of the locking and unlocking dial head 140 can be applied to the first lock tongue 151 and the second lock tongue 152 through the transmission mechanism 160, thereby driving the first lock tongue 151 and the second lock tongue 152 to move.

[0054] Exemplarily, the first locking tongue 151 is an oblique tongue, the first locking tongue 151 is extended by the elastic element, and the first locking tongue 151 is retracted by the locking and unlocking dial head 140. The second locking tongue 152 is a square tongue, and the second locking tongue 152 is extended by the locking and unlocking dial head 140.

[0055] It should be noted that the locks in the prior art are basically driven by turning the key to drive the locking and unlocking dial to rotate, thereby driving the lock tongue to move through the transmission mechanism. Therefore, the transmission mechanism 160 can refer to the transmission mechanism setting of the locks in the related art, and the specific structure of the transmission mechanism 160 will not be described in detail here.

[0056] In some embodiments, the lock 100 further includes a driver 170. Exemplarily, the driver 170 includes a rotary motor. The driver 170 is drivingly connected to the transmission mechanism 160, so that the driver 170 can be used to drive the lock tongue 150 to move. In this way, the lock 100 can have the function of automatic unlocking.

[0057] In some embodiments, the lock 100 includes a main lock 100a, a first secondary lock 100b and a second secondary lock 100c. The lock body portion including the first lock tongue 151 and the second lock tongue 152 can be referred to as the main lock 100a, and the first secondary lock 100b and the second secondary lock 100c are respectively arranged at intervals at the upper and lower ends of the main lock 100a. The rotating locking and unlocking dial 140 can also be used to drive the first secondary lock 100b tongue of the first secondary lock 100b to extend and retract, and drive the second secondary lock 100c tongue of the second secondary lock 100c to extend and retract. It should be noted that the structures of the first secondary lock 100b and the second secondary lock 100c can refer to the secondary lock settings of the lock in the relevant technology, and will not be described in detail here.

[0058] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0059] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the embodiments of the present application, and the scope of the embodiments of the present application is defined by the appended claims and their equivalents.

Claims

1. A lock (100), characterized in that: include: A base (110), a lock core dial (120), a speed reduction mechanism (130), a locking and unlocking dial (140) and a lock tongue (150); The lock core dial head (120) is rotatably connected to the base (110), and the lock core dial head (120) can rotate when driven by a key. The speed reduction mechanism (130) is arranged on the base (110), and the speed reduction mechanism (130) comprises a first gear (131) and a second gear (132) which are transmission-connected, and the ratio of the rotation speed of the first gear (131) to the rotation speed of the second gear (132) is greater than 1. The lock core dial head (120) is used to drive the first gear (131) to rotate, and the second gear (132) is transmission-connected to the locking and unlocking dial head (140), and the locking and unlocking dial head (140) is rotatably connected to the base (110), and the second gear (132) is used to drive the locking and unlocking dial head (140) to rotate, and the locking and unlocking dial head (140) is used to drive the lock tongue (150) to move.

2. The lock (100) according to claim 1, characterized in that: The first gear (131) is provided with a notch portion (1311); the lock core dial head (120) comprises a rotating portion (121) and a toggle portion (122) connected to each other; the first gear (131) is arranged around the outside of the rotating portion (121); and the toggle portion (122) is arranged in the notch portion (1311).

3. The lock (100) according to claim 1, characterized in that: The speed reduction mechanism (130) further comprises a third gear (133) and a fourth gear (134); the third gear (133) is meshed with the first gear (131) and the fourth gear (134) respectively; and the fourth gear (134) is transmission-connected with the second gear (132).

4. The lock (100) according to claim 3, characterized in that: The first gear (131) is a sector gear, the first gear (131) is arranged around the outside of the rotating part (121) of the lock core dial head (120), and the moving part (122) of the lock core dial head (120) is arranged in the notch part (1311) of the first gear (131); The speed reduction mechanism (130) further comprises a fifth gear (135), the pitch circle diameter of the fifth gear (135) being equal to the pitch circle diameter of the third gear (133), the fifth gear (135) being meshed with the fourth gear (134), and when the third gear (133) is opposite to the notch portion (1311), the fifth gear (135) being meshed with the first gear (131).

5. The lock (100) according to claim 4, characterized in that: The pitch circle diameter of the third gear (133) is smaller than the pitch circle diameter of the first gear (131), and the pitch circle diameter of the third gear (133) is smaller than the pitch circle diameter of the fourth gear (134).

6. The lock (100) according to claim 3, characterized in that: The speed reduction mechanism (130) further comprises a sixth gear (136), the pitch circle diameter of the sixth gear (136) being smaller than the pitch circle diameter of the fourth gear (134), the sixth gear (136) being coaxially connected with the fourth gear (134), the sixth gear (136) being capable of rotating synchronously with the fourth gear (134), and the sixth gear (136) being transmission-connected with the second gear (132).

7. The lock (100) according to claim 6, characterized in that: The speed reduction mechanism (130) further comprises a seventh gear (137), the pitch circle diameter of the seventh gear (137) being smaller than the pitch circle diameter of the second gear (132), and the seventh gear (137) being meshed with the sixth gear (136) and the second gear (132) respectively.

8. The lock (100) according to claim 7, characterized in that: The rotating shaft of the first gear (131), the rotating shaft of the fourth gear (134), the rotating shaft of the seventh gear (137) and the rotating shaft of the second gear (132) are all parallel to each other and coplanar.

9. The lock (100) according to claim 1, characterized in that: The second gear (132) is provided with a boss (1321) protruding along its own axial direction, and the locking and unlocking dial head (140) is connected to the boss (1321).

10. The lock (100) according to any one of claims 1 to 9, characterized in that: The ratio of the rotation speed of the first gear (131) to the rotation speed of the second gear (132) is greater than or equal to 2 and less than or equal to 4.

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