CN1707140A - gear transmission - Google Patents

Abstract

A gear speed-changing device is used for receiving the driving of a driving element to drive a transmission belt. The gear speed changing device comprises a first belt gear set, a second belt gear set and a switching gear set. The first belt gear set comprises at least one first belt gear, and the second belt gear set is separated from the first belt gear set and comprises at least one second belt gear. The transmission belt is meshed with the first belt gear and the second belt gear simultaneously, and when any one belt gear is rotated, the transmission belt can be driven by the belt gear. The switching gear set is connected with the driving element and comprises at least one switching gear which can be selectively meshed with the first belt gear set or the second belt gear set. When the switching gear set is engaged with the first belt gear set, the driving element drives the transmission belt with a first gear ratio, and when the switching gear set is engaged with the second belt gear set, the driving element drives the transmission belt with a second gear ratio.

Description

gear transmission

technical field

The invention relates to a gear transmission device, in particular to a gear transmission device used in image scanning equipment.

Background technique

The gear transmission device is used in equipment that needs to change the moving speed, such as image scanning equipment, etc. Image scanning equipment scans image files (such as patterns, posters, etc.) or text files (such as books, leaflets, etc.) with multiple resolutions, and then converts the original image on the physical object into an electronic form for storage. The so-called resolution refers to the number of dots per inch (DotPer Inch, DPI) when analyzing files in the image scanning equipment. For example, 600DPI means that the scanning module scans image files by analyzing 600 pixels per inch. Of course, under different resolution requirements, the scanning speed of the image scanning device must be adjusted accordingly. Most of the known image scanning devices directly adjust the speed of the driving elements to achieve the purpose of controlling the moving speed of the scanning module. However, the rotational speed and torque of the driving element have a certain range, so the problem of insufficient torque often occurs, and if a driving element with a higher torque is used, the cost must be increased.

Therefore, at present, a gear transmission device is often installed between the driving element and the transmission belt to improve the shortcoming of insufficient torque of the driving element. Please refer to FIG. 1 . FIG. 1 is a schematic diagram of a conventional image scanning device 10 with a gear transmission device 110 . The conventional image scanning device 10 includes a scanning module 102 , a driving belt 104 , a driving element 106 , a driving gear 108 and a gear transmission device 110 .

The scanning module 102 is used for scanning image objects, and the scanning module 102 is installed on the driving belt 104, and when the belt is driven, it can be accompanied by the driving. The drive element 106 and the drive gear 108 are interconnected (concentrically designed as known) such that the drive gear 108 rotates at a fixed rate when the drive element 106 is actuated. The driving gear 108 is connected with the gear transmission device 110 at the same time, so that the gears contained in the gear transmission device 110 also rotate at the same time to drive the transmission belt 104 connected with the gear transmission device 110 .

The gear transmission device 110 includes at least two sets of reduction gear sets 112 , 114 with different reduction ratios, a belt gear 116 and a switching gear set 118 . The switching gear set 118 keeps meshing with the drive gear 108 and is used to switch between the two reduction gear sets 112 , 114 . Therefore, the integral gear transmission 110 has to utilize two different reduction ratios to engage the belt gear 116 . Driven by the driving element 106 , the transmission belt 104 can be driven at different speeds, and then the scanning module 102 on the transmission belt 104 can be moved. The so-called reduction ratio means that the number of teeth of the reduction gear is more than that of the drive gear, so that the drive gear can only drive the reduction gear set to rotate less than one revolution for one revolution. If the design of the number of teeth of the gear is changed, the requirements of different speeds can be achieved.

As shown in FIG. 1 , in the conventional gear transmission device 110 , two sets of reduction gear sets 112 , 114 with different reduction ratios mesh with the belt gear 116 at the same time, which will cause unnecessary noise when using the conventional technology. For example, when the switching gear set 118 is selected to mesh with the reduction gear set 112 to drive the belt gear 116 , the belt gear 116 will not only rotate the transmission belt 104 , but also rotate another set of reduction gear set 114 at the same time. Another set of reduction gear set 114 is passively driven by the belt gear 116, which does not have any effect on the entire gear transmission device 110, so it can be said to be redundant. This unnecessary rotation will further generate unnecessary noise at the meshing place between the reduction gear set 114 and the belt gear 116 . Similarly, when the switching gear set 118 selects to mesh with the reduction gear set 114, it will also cause the reduction gear set 112 to idle and generate unnecessary noise.

Unnecessary rotation of the gear set, on the one hand, due to meshing with the belt gear, unnecessary noise will be generated at the meshing place during rotation, and on the other hand, it will increase the loss of the gear. Scanning Therefore, in order to improve the problems caused by the simultaneous meshing of belt gears and reduction gears in the known technology, it is necessary to propose a new gear transmission design, so that the belt gear and the two reduction gear sets can be separated from each other for transmission.

Contents of the invention

The technical problem to be solved by the present invention is to provide a low-noise gear transmission device to solve the problem of at least one set of reduction gear sets idling in the known gear transmission device and effectively reduce the noise of the gear transmission device.

For this reason, the present invention proposes a kind of gear transmission device, in order to accept the drive of a drive element and drive a transmission belt, this gear transmission device comprises:

a first belt gear set, including at least one first belt gear, the transmission belt is connected to the first belt gear for transmission;

a second belt gear set, separate from the first belt gear set, including at least one second belt gear to which the drive belt is also connected for transmission; and

a switching gear set connected to the driving element, including at least one switching gear for selectively engaging the first belt gear set or the second belt gear set;

Wherein, the transmission belt is engaged with the first belt gear and the second belt gear at the same time, and when the switching gear set is engaged with the first belt gear set, the driving element drives the transmission belt with a first gear ratio , when the switching gear set meshes with the second belt gear set, the driving element drives the transmission belt with a second gear ratio.

In the above-mentioned gear transmission device, a tension adjusting element is further arranged between the first belt gear set and the second belt gear set, and the transmission belt is also connected to the tension adjusting element to adjust the received tension.

As described above in the gear transmission device, the tension adjusting element comprises:

a pulley for connecting the drive belt; and

A tension adjusting spring is connected with the belt pulley to adjust the tension of the transmission belt.

As mentioned above in the gear transmission device, the first belt gear includes a pulley to connect with the transmission belt.

According to the above gear transmission device, the second belt gear includes a pulley to connect with the transmission belt.

According to the above-mentioned gear transmission device, the switching gear set further includes a driving gear, which is connected with the driving element and meshes with the switching gear.

In the above-mentioned gear transmission device, the switching gear set further includes a moving link to move the switching gear, so that the switching gear can selectively mesh with the first belt gear set or the second belt gear set, and at the same time maintain The switching gear meshes with the driving gear.

The present invention further proposes an image scanning device, comprising:

a transmission belt;

A scanning module installed on the transmission belt;

a driving element;

a first belt gear set, including at least one first belt gear, the transmission belt is connected to the first belt gear for transmission;

a second belt gear set, separate from the first belt gear set, including at least one second belt gear to which the drive belt is also connected for transmission; and

a switching gear set connected to the driving element, including at least one switching gear for selectively engaging the first belt gear set or the second belt gear set;

Wherein, the transmission belt is engaged with the first belt gear and the second belt gear at the same time, and when the switching gear set is engaged with the first belt gear set, the driving element drives the transmission belt with a first gear ratio , when the switching gear set meshes with the second belt gear set, the driving element drives the transmission belt with a second gear ratio.

In the above-mentioned image scanning device, a tension adjustment element is further arranged between the first belt gear set and the second belt gear set, and the transmission belt is also connected to the tension adjustment element to adjust the tension it receives.

As described above in the image scanning device, the tension adjustment element includes:

a pulley for connecting the drive belt; and

A tension adjusting spring is connected with the belt pulley to adjust the tension of the transmission belt.

As mentioned above in the image scanning device, the first belt gear includes a pulley to connect with the transmission belt.

As mentioned above in the image scanning device, the second belt gear includes a pulley to connect with the transmission belt.

According to the above image scanning device, the switching gear set further includes a driving gear, which is connected with the driving element and engages with the switching gear.

In the above-mentioned image scanning device, the switching gear set further includes a moving link to move the switching gear, so that the switching gear can selectively mesh with the first belt gear set or the second belt gear set, and at the same time maintain The switching gear meshes with the driving gear.

In the image scanning device mentioned above, the driving element is a stepping motor.

As mentioned above in the image scanning device, the scanning module includes an electrical coupling element.

According to the above image scanning device, the scanning module includes a contact image sensing element.

To sum up, an image scanning device proposed by the present invention includes: a driving belt, a scanning module, a driving element, a first belt gear set, a second belt gear set, and a switching gear set. The scanning module is installed on the transmission belt so that when the belt is driven, it is driven simultaneously. The first belt gear set includes at least one first belt gear, and the transmission belt is connected to the first belt gear for transmission. The second belt gear set, which is separated from the first belt gear set, includes at least one second belt gear, and the transmission belt is also connected to the second belt gear for transmission. The switching gear set, connected with the driving element, includes at least one switching gear for selectively engaging the first belt gear set or the second belt gear set.

When the switching gear set meshes with the first belt gear set, the driving element drives the transmission belt with a first gear ratio. When the switching gear set meshes with the second belt gear set, the driving element drives the transmission belt with a second gear ratio.

Therefore, when the switching gear of the present invention is switched between two sets of belt gears, since the belt gears do not contact each other, no idling phenomenon will occur. The problem of idling of the reduction gear set in the known technology is effectively improved.

Description of drawings

FIG. 1 is a schematic diagram of a conventional image scanning device with a gear transmission device.

FIG. 2 is a schematic diagram of the gear transmission device of the present invention applied to an image scanning device.

FIG. 3 is a schematic diagram of the gear transmission device in FIG. 2 .

FIG. 4 is a schematic view of adding a tension adjusting element and a moving link in FIG. 3 .

Explanation of reference numbers:

20. Image scanning equipment 202. Transmission belt

204. Scanning module 206. Driving components

208. Driving gear 210. Gear transmission device

212. The first belt gear set 2122. The first belt gear

2124. Belt pulley 214. Second belt gear set

2142. Second belt gear 2144. Pulley

216. Switch gear set 2162. Switch gear

30. Tension adjustment element 32. Pulley

34. Tension adjustment spring 40. Moving link

Detailed ways

The present invention provides a gear transmission device, which is suitable for use in equipment that needs to change the transmission speed, such as image scanning equipment. Please refer to FIG. 2 . FIG. 2 is a schematic diagram of a gear transmission device 210 of the present invention applied to an image scanning device 20 . The image scanning device 20 includes a driving belt 202 , a scanning module 204 , a driving element 206 , a driving gear 208 and a gear transmission device 210 . It can be known from FIG. 2 that the driving gear 208 connected to the driving element 206 can drive the gear built in the gear transmission device 210 by the actuation of the driving element 206 . Since the gear transmission device 210 has more than two gear sets with different gear ratios, the transmission belt 202 can be driven at different speeds under different gear combinations. The scanning module 204 located on the transmission belt 202 can analyze images with various resolutions at different moving speeds.

The transmission belt 202 is connected to the gear transmission device 210, and its material is made of a slightly elastic material such as rubber. The transmission belt 202 is tightly attached to the gears in the gear transmission device 210 , and the scanning module 204 is fixed on the transmission belt 202 , so when the transmission belt is driven by the gear transmission device 210 , it will drive the scanning module 204 . The scanning module 204 uses an image sensing element such as a Charge Coupled Device (CCD) or a Contact Image Scanner (CIS) to scan images.

The driving element 206 adopts an element that generates power such as a stepping motor. Since components such as stepping motors have a certain range of rotation speed and torque limit, if you want to adjust the driving components to achieve different moving speeds, the situation of insufficient torque often occurs. Therefore, the present invention fixes the driving element 206 at a reasonable range of rotational speed and torque requirements, and changes the moving speed of the scanning module 204 through the gear transmission device 210 connected to the driving element 206 .

The gear transmission device 210 includes a plurality of gear combinations to match different gear ratios. Different gear ratios mean that the drive belt 202 will be driven at different speeds. The gear transmission device 210 of the present invention includes a first belt gear set 212 , a second belt gear set 214 and a switching gear set 216 . Although the transmission belt 202 is tightly attached to the first belt gear set and the second belt gear set, the two sets of gears are separated from each other, which is a feature of the present invention. A switching gear set 216 is connected to the drive gear 208 and selectively engages the first belt gear set 212 or the second belt gear set 214 . Next, the present invention will be described with an embodiment using the least number of gears. Please refer to FIG. 3 , which is a schematic diagram of the gear transmission device 210 in FIG. 2 . For convenience of explanation, only two sets of gear sets are shown in FIG. 2 and FIG. 3 . In FIG. 3 , the first belt gear set 212 only includes a first belt gear 2122 to mesh with the switching gear 2162 in the switching gear set. The drive belt 202 is connected to a pulley 2124 on the first belt gear 2122 . The belt pulley 2124 and the first belt gear 2122 have the same axis, so that when the first belt gear 2122 is meshed with the switch gear 2162 and rotates, it rotates and drives the transmission belt 202 attached thereto. The second belt gear set 214 only includes a second belt gear 2142 . The transmission belt 202 is connected to the pulley 2144 on the second belt gear 2142 . The belt pulley 2144 and the second belt gear 2142 have the same axis, so that when the second belt gear 2142 meshes with the switching gear 2162 and rotates, it will rotate accordingly and drive the transmission belt 202 attached thereto.

When the switching gear 2162 is located at point A of the dotted line in FIG. 3 , it meshes with the first belt gear 2122 , and the driving element 206 drives the transmission belt 202 with a first gear ratio. When the switching gear 2162 is located at the dotted line point B in FIG. 3 , it meshes with the second belt gear 2142 , and the driving element 206 drives the transmission belt 202 with a second gear ratio. In FIG. 3 , if the scanning module 204 is driven by the first gear ratio, a resolution of 600 DPI will be obtained; if the scanning module 204 is driven by the second gear ratio, a resolution of 1200 DPI will be obtained. The gear ratio referred to here means that the number of teeth of the switching gear is different from that of the belt gear. By designing different gear ratios, different moving speeds can be converted.

In this embodiment, each gear set only uses one gear to achieve the effect that the prior art must use a combination of multiple gears to achieve, so it will save more cost than the prior art. And the application of less gears, plus the fact that each gear set is independent and does not contact with other gear sets, will effectively reduce the noise generated when the gear sets are meshed with each other.

It is emphasized here that, for those skilled in the art, in order to avoid specific embodiments of the present invention, each gear set may use more than one gear. However, this change in the number of gears and the connection mode should be a reasonable deformation of the speed change gear device of the present invention. Therefore, regardless of the number of gears used in each gear set, as long as the spirit of the present invention that each belt gear set is separated and not connected, all belong to the scope of the present invention.

Next, please refer to FIG. 4 . FIG. 4 is a schematic view of adding a tension adjusting element 30 and a moving link 40 in FIG. 3 . Most of the elements in FIG. 4 and FIG. 3 are the same, the difference is that a tension adjustment element 30 is arranged between the first belt gear 2122 and the second belt gear 2142, and the transmission belt 202 is also connected to the tension adjustment element 30 to adjust the tension it receives. And the switching gear 2162 is connected with a moving link 40 to move the switching gear 2162, so that the switching gear 2162 can selectively engage the first belt gear 2122 or the second belt gear set 2142, and simultaneously keep the switching gear 2162 and the driving gear 208 engage.

Since the transmission belt 202 is closely attached to the first belt gear 2122 and the second belt gear 2142, the transmission belt will be affected by a certain tension. The purpose of adding the tension adjustment device 30 is to release the tension on the transmission belt to avoid transmission The belt is broken. In one embodiment, the tension adjusting element 30 includes a pulley 32 and a tension adjusting spring 34 . The pulley 32 is used to connect the transmission belt 202 . The tension adjusting spring 34 is connected with the pulley 32 to adjust the tension of the drive belt. In this embodiment, the switching gear 2162 is switched between different positions (A, B) by means of the moving link 40 .

By the description of the above preferred specific embodiments, it can be clearly found that the present invention obviously has the following advantages:

1. The gear transmission device is used to change the moving speed of the scanning module, which solves the problem of insufficient torque of the driving components.

2. The number of gears can be effectively reduced, so that the cost of the gear transmission device is low and the noise is reduced.

3. Since the two sets of belt gears are not connected to each other, when the switching gear meshes with one set of belt gears, although the other set of belt gears is already rotating at the same time, it will not rotate because it is not connected to any gear. Make noise. And known technology is to join a belt gear with two groups of reduction gear sets, so when driving belt gear with one of them, another group will idle because of belt gear, and will send out noise with belt gear engagement place.

Through the above detailed description of the preferred embodiments, it is hoped that the features and spirit of the present invention can be described more clearly, and the scope of the present invention is not limited by the preferred embodiments disclosed above. On the contrary, the intention is to cover various changes and equivalent arrangements within the scope of the claimed patent scope of the present invention.

Claims (17)

1, a kind of speed change gear, transmission one drivign belt in order to the drive of accepting a driving element, this speed change gear comprises:

One first belt-gear combination comprises at least one first belt gear, and this drivign belt connects this first belt gear to carry out transmission;

One second belt-gear combination, disconnected from each other with this first belt-gear combination, comprise at least one second belt gear, this drivign belt also connects this second belt gear to carry out transmission; And

One change gear group is connected with this driving element, comprises at least one change gear, in order to optionally to mesh this first belt-gear combination or this second belt-gear combination;

Wherein, this drivign belt is engaged in this first belt gear and this second belt gear simultaneously, and when this switching gear train is meshed with this first belt-gear combination, this driving element drives this drivign belt with one first gear ratio, when this switching gear train was meshed with this second belt-gear combination, this driving element drove this drivign belt with one second gear ratio.

2, speed change gear as claimed in claim 1 is characterized in that, further between this first belt-gear combination and this second belt-gear combination one tension regulating element is set, and this drivign belt also connects this tension regulating element to adjust suffered tension force.

3, speed change gear as claimed in claim 2 is characterized in that, this tension regulating element comprises:

One belt pulley is in order to connect this drivign belt; And

One tension adjustment spring connects this belt pulley, in order to regulate the suffered tension force of this drivign belt.

4, speed change gear as claimed in claim 1 is characterized in that, this first belt gear comprises a belt pulley, to connect this drivign belt.

5, speed change gear as claimed in claim 1 is characterized in that, this second belt gear comprises a belt pulley, to connect this drivign belt.

6, speed change gear as claimed in claim 1 is characterized in that, this switching gear train further comprises an actuation gear, and this actuation gear is connected with this driving element, and meshes this change gear.

7, speed change gear as claimed in claim 6, it is characterized in that, this switching gear train further comprises a mobile link, to move this change gear, make this change gear optionally be meshed this first belt-gear combination or second belt-gear combination, and keep this change gear and the engagement of this actuation gear simultaneously.

8, a kind of image scanner comprises:

One drivign belt;

The one scan module is installed on this drivign belt;

One driving element;

One first belt-gear combination comprises at least one first belt gear, and this drivign belt connects this first belt gear to carry out transmission;

One second belt-gear combination, disconnected from each other with this first belt-gear combination, comprise at least one second belt gear, this drivign belt also connects this second belt gear to carry out transmission; And

One change gear group is connected with this driving element, comprises at least one change gear, in order to optionally to mesh this first belt-gear combination or this second belt-gear combination;

Wherein, this drivign belt is engaged in this first belt gear and this second belt gear simultaneously, and when this switching gear train is meshed with this first belt-gear combination, this driving element drives this drivign belt with one first gear ratio, when this switching gear train was meshed with this second belt-gear combination, this driving element drove this drivign belt with one second gear ratio.

9, image scanner as claimed in claim 8 is characterized in that, further between this first belt-gear combination and this second belt-gear combination one tension regulating element is set, and this drivign belt also connects this tension regulating element to adjust suffered tension force.

10, image scanner as claimed in claim 9 is characterized in that, this tension regulating element comprises:

One belt pulley is in order to connect this drivign belt; And

One tension adjustment spring connects this belt pulley, in order to regulate the suffered tension force of this drivign belt.

11, image scanner as claimed in claim 8 is characterized in that, this first belt gear comprises a belt pulley, to connect this drivign belt.

12, image scanner as claimed in claim 8 is characterized in that, this second belt gear comprises a belt pulley, to connect this drivign belt.

13, image scanner as claimed in claim 8 is characterized in that, this switching gear train further comprises an actuation gear, and this actuation gear is connected with this driving element, and meshes this change gear.

14, image scanner as claimed in claim 13, it is characterized in that, this switching gear train further comprises a mobile link, to move this change gear, make this change gear optionally be meshed this first belt-gear combination or second belt-gear combination, and keep this change gear and the engagement of this actuation gear simultaneously.

15, device of image scanning as claimed in claim 8 is characterized in that, this driving element is a stepper motor.

16, device of image scanning as claimed in claim 8 is characterized in that, this scanning module comprises a charge coupled device.

17, device of image scanning as claimed in claim 8 is characterized in that, this scanning module comprises a contact-type image sensing element.

Images